Dynamic Coding

How to transform XML into XHTML using XSLT through XslCompiledTransform class

2009-12-13T22:52:00.042+05:30

XSLT (XSL Transformations):

XML - based language used for the transformation of XML documents into HTML documents. The transformation may happen dynamically either on the client or on the server.

XslCompiledTransform class:

The XslCompiledTransform class is an XSLT processor that supports the XSLT 1.0 syntax. It is a new implementation and includes performance gains when compared to the obsolete XslTransform class.

Example :

"Data.Xml" file

<xml version="1.0" ?>
<books>
<book>
<id> 1 <id>
<name> XML Concepts <name>
<author > AUTHOR1 < author>
<price > 40.00 <price>
<book>
< book>
< id> 2 <id>
<name> Website Programmingname <name>
<author> AUTHOR2 <author>
<price> 50.00 <price >
<book>
<book>
<id> 3 <id>
<name> LINQ Concepts <name>
<author> AUTHOR3 <author>
<price> 10.00 <price>
<book>
<books>

Data.XSLT file

<xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl=http://www.w3.org/1999/XSL/Transform>
<xsl:output method="html"/>
<xsl:template match="/">
<html>
<head>
<title>How to use XslCompiledTransform Class in asp.net</title>
</head>
<body>
<h2 style="color:DarkOrange; font-style:italic;">
XSLT - Using XslCompiledTransform</h2>
<hr width="370" align="left" color="Orange" />
<br />
<table border="1" cellpadding="5" cellspacing="0" bordercolor="CornFlowerBlue">
<tr bgcolor="DodgerBlue" style="color:White; font-weight:bold">
<td align="center">Name of Book</td>
<td>Name of Author</td>
<td>Book Price</td>
</tr>
<xsl:for-each select="books/book">
<tr bgcolor="Snow" style="color:Black; font-weight:normal; font-style:italic;">
<td height="10">
<xsl:value-of select="name"/>
</td>
<td height="10">
<xsl:value-of select="author"/>
</td>
<td height="10" style="font-weight:bold;">
<xsl:value-of select="price"/>
</td>
</tr>
</xsl:for-each>
</table>
</body>
</html>
<xsl:template>
<xsl:stylesheet>

Transform XML into HTML using XslCompiledTransform class:

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;
using System.Xml;
using System.Xml.XPath;
using System.Xml.Xsl;

public partial class Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string xmlFilePath = Request.PhysicalApplicationPath + @"App_Data\Data.xml";
string xsltPath = Request.PhysicalApplicationPath + @"App_Data\Data.xslt";
XPathDocument xPathDoc = new XPathDocument(xmlFilePath);
XslCompiledTransform transform = new XslCompiledTransform();
transform.Load(xsltPath);
transform.Transform(xPathDoc, null, Response.Output);
}
}

Output of Above page is :

In .NET how to achieve Multiple Inheritance using Interface

2009-08-19T22:54:00.007+05:30

Diamond Problem :

The Diamond problem is related to object oriented languages that allow multiple inheritance.As we know C# does not support multiple inheritance of classes, but it does support multiple inheritance through interfaces. Therefore, the same ambiguity may arise unless explicit interface implementation is used. Going explicitly, we can have different implementations to the same method. The problem is solved.

namespace MulipleInheritance
{

public interface IntBC
{
void Display();
}

public interface IntA : IntBC
{
new void Display();
}

public interface IntB : IntBC
{
new void Display();
}

// C class implements the IntA and IntB interfaces
public class C : IntA, IntB
{
// explicitly implement the Display() method of the IntA interface
void IntA.Display()
{
Console.WriteLine("IntA implementation of Display()");
}
// implement the Display() method of the IntB interface
public void Display()
{
Console.WriteLine("IntB implementation of Display()");
}
}

public class MainClass
{
public static void Main()
{
C ObjC = new C();
Console.WriteLine("Calling ObjC.Display()");
ObjC.Display();
// cast ObjC to IntB
IntA RefIntA = ObjC as IntA;
Console.WriteLine("Calling RefIntA.Display()");
RefIntA.Display();
// cast ObjC to IntA
IntB RefIntB = ObjC as IntB;
Console.WriteLine("Calling RefIntB.Display()");
RefIntB.Display();
}
}

}

Output :

Calling ObjC.Display()
IntB implementation of Display()
Calling RefIntA.Display()
IntA implementation of Display()
Calling RefIntB.Display()
IntB implementation of Display()

In Class C, first Display() method is explicitly implemented for IntA Interface. Explicit implementation is not needed for the second Display() method, because previous statement already did that and the method implementation is automatically assumed to IntB interface. In order to call explicit implementation method casting is required.

Why Multiple inheritance is not supported in .NET

2009-08-19T20:05:00.005+05:30

Multiple Inheritance:

Multiple inheritance may allow you to write compact code but it has some program difficulties like "diamond problem" for example

Diamond problem :

class BaseClass
{
public abstract void Display();
}

class A : BaseClass
{
public override void Display()
{
Debug.WriteLine("First Child A");
}
}

class B : BaseClass
{
public override void Display()
{
Debug.WriteLine("Second Child B");
}
}

//Now Suppose that c# support multiple inheritance

class C : A, B
{
}

public class MainClass
{
public static void main()
{
C ObjC =new C();
ObjC.Display();
}
}

By excuting ObjC.Display() method Diamond problem is generated. It means which Display method going to executed.

Exception Handling in SQL Server 2005

2009-08-13T19:48:00.006+05:30

Exception Handling in 2000:

In SQL Server 2000 Exception handling was implmented with the help of @@ERROR statement. Each and every statement you have to check the value of Error number. Practically it is not easiest things to do.

Exception Handling in 2005:

In .NET programming exception are handled with help of TRY - CATCH block. Similarly TRY - CATCH block is implmented in SQL Server 2005. When you are exceuting the procedure if error occured then catch block statements are exceuted. This technique is applicable only for the run time errors.

The following functions are used to get the error details

ERROR_NUMBER()
ERROR_SEVERITY()
ERROR_STATE()
ERROR_PROCEDURE()
ERROR_LINE()
ERROR_MESSAGE()

Example:

CREATE PROCEDURE PROCEXCEPHANDLING

BEGIN

BEGIN TRY

SELECT 100/0

END TRY

BEGIN CATCH

Select

ERROR_NUMBER() AS ErrNo,

ERROR_SEVERITY() AS ErrSev,

ERROR_STATE() AS ErrState,

ERROR_PROCEDURE() AS ErrProc,

ERROR_LINE() AS ErrLine,

ERROR_MESSAGE() AS ErrMsg

END CATCH

END

Executing the above procedure

Exec PROCEXCEPHANDLING

Output of above statement is

Static Constructor in C#

2009-08-11T15:34:00.005+05:30

Static Constructors:

It is a Special type of constructor. It gets called before the creation of first object of class(Probably at the time of loading an assembly).

Rules to create a static constructor:

There is no access modifier require to define a static constructor.
There may be only one static constructor in a class.
The static constructor may not have any parameters.
This constructor may only access the static members of the class

Static constructor is used to initialize static data members as soon as the class is referenced first time.You can also initialize static data members where we declare them in the code.

Like this :
public static int id = 10;

But value of one static member may depend upon the value of another static member .In order to handle such cases you need some manipulation before static members going to be initialize.
This you can achieve through static constructors.

namespace StaticConstructor
{

class MainClass
{
static void Main(string[] args)
{
Console.WriteLine("Id value is " + ClsStaticConstructor.id);
}
}

class ClsStaticConstructor
{
public static int id;

static ClsStaticConstructor()
{
if (Sample.Value == 10)
id = 20;
else
id = 40;
}
}

public class Sample
{
public static int Value = 10;
}

}

Output:

Id value is : 20

PIVOT function in SQL Server 2005

2009-07-26T23:05:00.004+05:30

PIVOT:

This is one of the most important enhancements to TSQL in SQL 2005 and is extremely useful for generating reports based on cross tab values.The PIVOT operator rotates rows into columns, optionally performing aggregations or other mathematical calculations along the way.

The syntax for the PIVOT relational operator is:

FROMtable_source
PIVOT ( aggregate_function ( value_column )
FOR pivot_column
IN (<column_list>)
) table_alias

table_source : The table where the data will be pivoted.
aggregate_function : The aggregate function that will be used against the specified column. pivot_column : The column that will be used to create the column headers.
column_list : The values to pivot from the pivot column.

For Example:

create table parameter
(
pid int,
pname varchar(50)
)
GO

create table TransactionInfo
(
TransId int,
pid int,
pvalue int
)
GO

insert into parameter values(1,'Para1')
GO
insert into parameter values(2,'Para2')
GO
insert into parameter values(3,'Para3')
GO
insert into parameter values(4,'Para4')
GO
insert into parameter values(5,'Para5')
GO

insert into TransactionInfo values(1,1,30)
GO
insert into TransactionInfo values(1,2,40)
GO
insert into TransactionInfo values(1,3,50)
GO
insert into TransactionInfo values(1,4,35)
GO
insert into TransactionInfo values(1,5,45)
GO
insert into TransactionInfo values(2,1,50)
GO
insert into TransactionInfo values(2,2,60)
GO
insert into TransactionInfo values(2,3,70)
GO
insert into TransactionInfo values(2,4,85)
GO
insert into TransactionInfo values(2,5,45)
GO

In TransactionInfo table row wise records are stored. If you need columnwise report we go for PIVOT functions.

select TransID,para1,para2,para3,para4,para5 from
(select a.pname,b.pvalue,TransID from parameter a,TransactionInfo b
where a.pid = b.pid and TransID in (1,2) ) as aa
pivot
(
sum(pvalue)
for pname in([para1],[para2],[para3],[para4],[para5])
) as bb
GO

The Following result set is obtained after executing the above query, which PIVOTS data based on the parameters thats been selected.

Output of above query is as follows

SQL Server 2005 - INTERSECT and EXCEPT operands.

2009-07-26T16:56:00.007+05:30

INTERSECT and EXCEPT operands:

Like Union and Union all SQL Server 2005 introduces INTERSECT and EXCEPT operands.

INTERSECT :

It is useful for retrieving only distinct rows that exist in both the left and right queries.

EXCEPT :

It is useful for retrieving only distinct rows that exist in the left query.

For example :

Create table DeptA

( DeptId int, DeptName varchar(40))

Create table DeptB

( DeptId int, DeptName varchar(40))

insert into DeptA values(10,'Sales')

insert into DeptA values(20,'Service')

insert into DeptA values(30,'Puchase')

insert into DeptB values(10,'Sales')

insert into DeptB values(20,'Service')

insert into DeptB values(30,'Marketing')

--Intersect

select * From DeptA

Intersect

Select * From DeptB

--Except

select * From DeptA

Except

Select * From DeptB

Step by Step procedure of CLR Integration in SQL Server 2005

2009-07-26T12:45:00.016+05:30

CLR integration in SQL Server 2005:

In T-SQL impossible when we need a stored procedure with some array-operations, text-parsing or complex math operations. However, it is quite easy if our Server allows us to deploy C# or VB.NET code that is used within the Server process. In other words, if we need complex procedural code, we can write it as managed code.

SQL Server 2005 we can write store procedure, triggers,user defined functions , user defined types etc in managed code(CLR) also. It acts as the operating system for the CLR when it is hosted inside SQL Server.

Procedure for Creating CLR integrated Store Procedure in SQL Server 2005 using Visual Studio 2005:

Open Visual Studio 2005 IDE.
· Go to menu File -> New -> Project.
· Within the “New Project” dialog box, select “database” (VB) as the project type and select “SQL Server Project” as the template. Provide your own project name, choose your own location and finally click OK.

You will be prompted with the “New Database Reference” dialog, where you need to provide the instance name of your SQL Server 2005 with database information.

When you are prompted for “SQL/CLR debugging” press “YES”.

Go to the Solution Explorer, right click on project and go to Add -> Stored Procedures

Select “Stored procedure” as in the template, provide the name of the stored procedure as “StoreProcedure1” and finally click add.

Add your code like this

Imports System
Imports System.Data
Imports System.Data.SqlClient
Imports System.Data.SqlTypes
Imports Microsoft.SqlServer.Server

Partial Public Class StoredProcedures1

Public Shared Sub SP_DisplayEmp()
Dim Con As New SqlConnection("context connection=true")
Try
Con .Open()
Dim Cmd As New SqlCommand("select eid,ename,sal from emp", Con)
Dim oReader As SqlDataReader
oReader = Cmd .ExecuteReader()
SqlContext.Pipe.Send(oReader)
Catch ex As Exception
SqlContext.Pipe.Send(ex.ToString())
End Try
End Sub

End Class

Here SqlContext.Pipe statement is an sql ouput statement.
After this ReBuild and Deploy the project through solution explorer.

Now new procedure named "SP_DisplayEmp" is added in master database. This procedure retrieve all the data which available in Emp table.

Open SQL server 2005 Query wizard and execute the following statements

use master
GO
--To enable SQL Server 2005 for CLR integration
EXEC sp_configure @configname = 'clr enabled', @configvalue = 1
RECONFIGURE WITH OVERRIDE
GO
create table emp
(
eid varchar(10),
ename varchar(40),
sal int
)
GO

insert into emp values('E01','Crys',81000)
GO
insert into emp values('E02','Jhon',72000)
GO
insert into emp values('E03','Gogul',90000)
GO

execute SP_DisplayEmp
GO

CLR integrated Procedure Ouput is

XML Serialization in .NET

2009-07-25T17:06:00.010+05:30

XML Serialization:

By using XML serialization only public properties and fields can be serialized.

If private members are to be serialized, other serialization methods should be used (Binary Serialization and SOAP Serialization).

It requires a parameterless constructor. This constructor is called during deserialization.

Serialized form of the object does not contain any type, assembly information of the class. Only the data is stored.

Using XML serialization not all the classes can be serialized. Classes that implement IDictionary cannot be serialized. E.g. Hashtables cannot be serialized. Arrays of objects can be easily serialized. Collections can be serialized but to serialize collections certain rules must be followed.

Null values are not serialized with XML serialization. To include the null members in the serialized form IsNullable attribute should be set to true.

For example: [ XmlElement( IsNullable = true ) ]

Here ClsSample is a Serializable class. It has private and Public members,

using System;
using System.Collections.Generic;
using System.Text;

namespace XMLSerilization
{
public class ClsSample
{
private int m_TotalCount = 5;
public String m_StrWord = "Ten";

public void ReAssignMemberValues()
{
m_TotalCount = 20;
m_StrWord = "Twenty";
}
public void DisplayMemberValueAfterDeSerialization()
{
Console.WriteLine("Private member value is " + m_TotalCount);
Console.WriteLine("Public member value is " + m_StrWord);
}
}
}

Following way you can Serialize and Deserialize the objects(through files)

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Xml;
using System.Xml.Serialization;

namespace XMLSerilization
{
public class ClsXML
{
public void ToXMLSerilization(Object objToXml, string filePath)
{
StreamWriter stWriter = null;
XmlSerializer xmlSerializer;
try
{
xmlSerializer = new XmlSerializer(objToXml.GetType());
stWriter = new StreamWriter(filePath);
xmlSerializer.Serialize(stWriter, objToXml);
}
catch (Exception exception)
{
throw exception;
}
finally
{
if (stWriter != null) stWriter.Close();
}
}

public object FromXMLSerilization(string filePath, Type type)
{
XmlSerializer xmlSerializer;
FileStream fileStream = null;
try
{
xmlSerializer = new XmlSerializer(type);
fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
object objectFromXml = xmlSerializer.Deserialize(fileStream);
return objectFromXml;
}
catch (Exception Ex)
{
throw Ex;
}
finally
{
if (fileStream != null) fileStream.Close();
}
}
}
}

//Main Class

using System;
using System.Collections.Generic;
using System.Text;

namespace XMLSerilization
{
public class Program
{
static void Main(string[] args)
{
ClsSample ObjSample;
ClsXML ObjXML;
ObjSample = new ClsSample();
ObjSample.ReAssignMemberValues();
ObjXML = new ClsXML();
//Serialize
ObjXML.ToXMLSerilization(ObjSample, "c:\\XMLSerialized.TXT");
ObjSample = null;
//Deserilize
ClsSample ObjDeseialXML;
ObjDeseialXML = (ClsSample) ObjXML.FromXMLSerilization("c:\\XMLSerialized.TXT", typeof(ClsSample)) ;
ObjDeseialXML.DisplayMemberValueAfterDeSerialization();
}
}
}

Output :
Private member value is 5
Public member value is Twenty

Actually reassigned value for the private member is 20 but you are unable to get that value in deserialized object. Because XML Serilization does not keep private members information

SOAP Serialization in .NET

2009-07-25T13:43:00.009+05:30

SOAP Serialization :

SOAP Serialization and Binary Serialization having many similar properties.

In SOAP Serialization private fields, type information including assembly, namespace, public key token information are also serialized.

Deserialization gives the same object as it was before serialization.

Serialization can be controlled to exclude a field using [NonSerialized] attribute.

[Serializable] attribute is used to mark a class as serializable.

Classes do not need to have a parameterless constructor. Because of performance issues, the constructor of the class is not called during deserialization.

Use if the serialization and deserialization platforms are not .NET.

Use if the message is sent through a firewall.

Here ClsSample is a Serializable class. It has private and Public members,

using System;
using System.Collections.Generic;
using System.Text;

namespace SOAPSerilization
{
[Serializable]
public class ClsSample
{
private int m_TotalCount = 5;
public String m_StrWord = "Ten";
public void ReAssignMemberValues()
{
m_TotalCount = 20;
m_StrWord = "Twenty";
}
public void DisplayMemberValueAfterDeSerialization()
{
Console.WriteLine("Private member value is " + m_TotalCount);
Console.WriteLine("Public member value is " + m_StrWord);
}
}
}

Following way you can Serialize and Deserialize the objects(through files)

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Soap;

namespace SOAPSerialization
{
public class ClsSOAP
{
//Serialization
public void ToSoapSerialization(Object objToSoap,string filePath)
{
IFormatter formatter;
FileStream fileStream = null;
try
{
fileStream = new FileStream(filePath,FileMode.Create, FileAccess.Write);
formatter = new SoapFormatter();
formatter.Serialize(fileStream, objToSoap);
}
catch (Exception exception)
{
throw exception;
}
finally
{
if (fileStream != null) fileStream.Close();
}
}

//Deserialization
public object FromSoapSerialization(string filePath)
{
IFormatter formatter;
FileStream fileStream = null;
try
{
fileStream = new FileStream(filePath,FileMode.Open, FileAccess.Read);
formatter = new SoapFormatter();
return formatter.Deserialize(fileStream);
}
catch (Exception exception)
{
throw exception;
}
finally
{
if (fileStream != null) fileStream.Close();
}
}
}
}

//Main Class
using System;
using System.Collections.Generic;
using System.Text;

namespace SOAPSerialization
{
public class Program
{
static void Main(string[] args)
{
ClsSample ObjSample;
ClsSOAP ObjSOAP;
ObjSample = new ClsSample();
ObjSample.ReAssignMemberValues();
ObjSOAP = new ClsSOAP();
//Serialize
ObjSOAP.ToSoapSerialization(ObjSample, "c:\\SOAPSerialized.TXT");
ObjSample = null;
//Deserilize
ClsSample ObjDeseialSOAP;
ObjDeseialSOAP = (ClsSample)ObjSOAP.FromSoapSerialization("c:\\SOAPSerialized.TXT");
ObjDeseialSOAP.DisplayMemberValueAfterDeSerialization();
}
}
}

Output:

Private member value is 20

Public member value is Twenty

Here both private and public members are serialized

ROLLUP in Sql Server

2009-07-24T21:13:00.006+05:30

it is used to Summarizing Data..

The ROLLUP operator is useful in generating reports that contain subtotals and totals. The ROLLUP operator generates a result set that is similar to the result sets generated by the CUBE operator.

ROLLUP generates a result set that shows aggregates for a hierarchy of values in the selected columns.

Checkout this example..

Create Table Student
(
StudentID int,
Student_Name Varchar(15),
SubjectName Varchar(15),
Marks_Scored numeric(18,1)
)

Insert into Student Values(1,'Babu', 'Tamil',90)
Insert into Student Values(1,'Babu', 'English',78)
Insert into Student Values(1,'Babu', 'Maths',88)
Insert into Student Values(1,'Babu', 'Science',88)
Insert into Student Values(1,'Babu', 'Social Science',92)

Insert into Student Values(2,'Ramesh', 'Tamil',92)
Insert into Student Values(2,'Ramesh', 'English',88)
Insert into Student Values(2,'Ramesh', 'Maths',98)
Insert into Student Values(2,'Ramesh', 'Science',99)
Insert into Student Values(2,'Ramesh', 'Social Science',90)

Insert into Student Values(3,'ram', 'Tamil',65)
Insert into Student Values(3,'Ram', 'English',68)
Insert into Student Values(3,'Ram', 'Maths',88)
Insert into Student Values(3,'Ram', 'Science',59)
Insert into Student Values(3,'Ram', 'Social Science',60)

select Student_Name,Sum(Marks_Scored) as Total
from Student
group by Student_Name
with rollup

Select
(Case When (Grouping(Student_Name)=1) Then 'G.Total' Else Student_Name End)as Student_Name,
(Case When (Grouping(SubjectName)=1) Then 'Total' Else SubjectName End)as SubjectName,
Sum(Marks_Scored) as Total
from Student group by Student_Name, SubjectName with rollup

Note :it will run sqlserver2005 and above

Serial Number using ROW_NUMBER (Transact-SQL)

2009-07-24T20:48:00.005+05:30

Serial No is possible for your table using ROW_NUMBER

ROW_NUMBER

Returns the sequential number of a row within a partition of a result set, starting at 1 for the first row in each partition.

Check out this Example

create table myTable
(
intNo int,
fname varchar(200),
mark numeric(5,2)
)

insert into mytable values(1,'xyz',89.45)
insert into mytable values(2,'xyz1',93.45)
insert into mytable values(3,'xyz2',35.45)
insert into mytable values(4,'xyz3',88.45)
insert into mytable values(5,'xyz4',73.45)

select ROW_NUMBER()OVER(ORDER BY mark DESC) AS 'Row Number' ,intNo,
fname,mark from MyTable

output

Note:it will run in sql server 2005 and above...

Difference between MSDE and SQL Server Express 2005

2009-07-23T21:39:00.017+05:30

SQL SERVER Express edition is a cut down version of SQL SERVER 2005 and the next evolution of MSDE(MSDE is a cut down version of SQL Server 2000).

MSDE maximum database size is 2GB but in SQL SERVER Express has around 4GB.

In terms of programming language support MSDE has only TSQL, but SQLSERVER Express has TSQL and .NET.

SQL SERVER Express does not have connection limitation, which MSDE had and was controlled through the Workload governer.

There was no XCOPY support for MSDE, SQL SERVER Express has it.

DTS is not present in SQL SERVER express while MSDE has it.

SQL SERVER Express has reporting services while MSDE does not.

SQL SERVER Express has native XML support and MSDE does not.

Database restore from SQL Server 7 ,SQL Server 2000 to SQL Server 2005

2009-07-23T19:26:00.004+05:30

it is possible to restore database from sql server 7, sql server 2000 to sql server 2005.
it can be achieved by using restore and with replace command

use master

restore database mydatabase from disk ='c:\mybackup.bak' with replace

Sql Server – Backup and Restore Database using SQL Script (T-SQL)

2009-07-23T19:12:00.004+05:30

it is easy to take backup in sql server using script without any External tools.
By SIMPLE ways.. as follows...

use master

create database mydatabase

backup database mydatabase to disk ='c:\mybackup.bak'

Yeah,i can be easily restore by simple steps...

use master

restore database mydatabase from disk ='c:\mybackup.bak'

thats all..

Parameter types in C# (Value,out,ref and params)

2009-07-21T22:09:00.006+05:30

Value parameters:

Value parameter is also called In parameter. A parameter declared with no modifiers is a
value parameter. Methods are permitted to assign new values to a value parameter. Such assignments only affect the local storage location and it has no effect on the actual argument given in the method invocation.

static void ParamMethod(int Param1)
{
Param1 = 100;
}
static void Main()
{
int Paravalue = 10;
ParamMethod(Paravalue);
Console.WriteLine(Paravalue);
}

//Here the output is 10

Reference Parameter:

Reference parameter declared with a ref modifier. It does not make a new storage location. Instead, a reference parameter represents the same storage location as the variable given as the argument in the method invocation. It should assigned to some value before it go for the method invocation.

static void ParamMethod(ref int Param1)
{
Param1 = 100;
}
static void Main()
{
int Paravalue = 10; //Here Paravalue should assign
ParamMethod(ref Paravalue);
Console.WriteLine(Paravalue);
}

//Here the output is 100

Output parameters:

Output parameter declared with an out. Similar to a reference parameter, an output parameter does not create a new storage location. Instead, an output parameter represents the same storage location as the variable given as the argument in the method invocation.Every output parameter of a method must be definitely assigned before the method returns.

static void ParamMethod(out int Param1)
{
Param1 = 100; //Here Param1 should assign
}
static void Main()
{
int Paravalue ;
ParamMethod(out Paravalue);
Console.WriteLine(Paravalue);
}

//Here the output is 100

Params:

The value passed for a "params" parameter can be either comma separated value list or a single dimensional array. "params" parameters are input only.

static int Summation(params int[] Param1)
{
int Sum =0;
foreach(int P in Param1)
{
Sum = Sum +P;
}
return Sum ;
}

static void Main()
{
Console.WriteLine(Summation(1,2,3));
}

//Here the output is 6

Serailization in .NET

2009-07-19T22:02:00.009+05:30

Serialization:

Serialization is the process of saving the state of an object in a persistent storage media in the form of linear stream of bytes. The object can be stored to a file, a database or even in the memory. Serialization in .NET is provided by the System.Runtime.Serialization namespace.

In order for a class to be serializable, it must have the attribute SerializableAttribute set
and all its members must also be serializable, except if they are ignored with the attribute NonSerializedAttribute. However, the private and public members of a class are always serialized by default. The SerializationAttribute is only used for the binary serialization.

[Serializable]
public class Student
{
private int StudentID;
public string StudentName;
public void dispaly()
{
Console.WriteLine("Student Name "+ StudentName);
}
}

Binary Serialization:

In Binary serialization the entire object state is saved. Both public and private members states are saved.

//The following way Student object is serialized
public void BinarySerialize(string filename, Student Stud)
{
FileStream fileStreamObject;
try
{
fileStreamObject = new FileStream(filename, FileMode.Create);
BinaryFormatter binaryFormatter = new BinaryFormatter();
binaryFormatter.Serialize(fileStreamObject, Stud);
}
finally
{
fileStreamObject.Close();
}
}

//The following way Deserialize the Student Object
public static object BinaryDeserialize(string filename)
{
FileStream fileStreamObject;

try
{
fileStreamObject = new FileStream(filename, FileMode.Open);
BinaryFormatter binaryFormatter = new BinaryFormatter();
return (binaryFormatter.Deserialize(fileStreamObject));
}
finally
{
fileStreamObject.Close();
}
}

Serialization is used to transportation of an object through a network.

How to Fix cross mark in Crystal report while exporting to Excel

2009-07-18T14:19:00.004+05:30

In your application, while exporting crystal report to Excel your getting cross mark in spite of image.Like this

Problem is not in the crystal report.Dont waste time your in Crystal report.

Solution is in your Business logic,check your size of the image/bitmap.

Ensure image height and width are same before exporting to crystal report.

it is working for me..Enjoy it..

How to Fix/Solution for Internet Explorer cannot open the Internet site and operation aborted in Blog

2009-07-17T20:29:00.010+05:30

In blog, your getting message like this Internet Explorer cannot open the internet site with following links and operation aborted...

Check out your Blog spot settings, where your Comment form placement in your blog. If it is Embedded below post like this...

Solution is simply and Easy,Change it Embedded below post to Full page.

it is working...

ahhahhha...Enjoy it...

How to Call Javascript function through CodeBehind(C#)

2009-07-12T13:57:00.033+05:30

Yeah,It is easy to Call javascript function through codebehind by using
Attributes.Add to the button.

use this code..

Button1.Attributes.Add("onclick", "return callingfn()");

Consider javascript as follows

function callingfn()

{

var objTextBox = document.getElementById('TextBox2');

objTextBox.value = "123";

return objTextBox.value();

}

</script>

whole code like this..

<html >

<title> Untitled Page</title>

{

var objTextBox = document.getElementById('TextBox2');

objTextBox.value = "123"

return objTextBox.value();

}

</script>

</head>

<body>

<div>

<table>

<tr>

<td>

<asp:TextBox ID="TextBox2" runat="server" > </asp:TextBox> </td>

</tr>

<tr>

</td>

</tr>

</table>

</div>

</form>

</body>

</html>

SQL Server 2000 Workload Governer

2009-07-06T21:52:00.005+05:30

Workload governor limits the performance of MSDE if the SQL engine receives more load than limit of MSDE(8 Cuncurrent connection).

Workload governor sits between the client and the database engine and counts the number of connections per database instance. If Workload governor finds that the number of connections exceeds eight connections, it starts stalling the connections and slowing down the database engine.

It does not limit the number of connections but makes the connection request go slow. By default 32,767 connections are allowed both for SQL SERVER and MSDE.

Difference between MSDE and SQL Server 2000

2009-07-06T21:02:00.010+05:30

MSDE(Microsoft Desktop Engine):

MSDE is a cut down version of the SQL SERVER database and free, redistributable software.

Differences:

A.Size:

In MSDE database size limited to 2GB.
In SQL Server database size limited to 1,048,516 TB1(1 Billion GB).

B.Performance:

Performance of MSDE degrades when maximum number of concurrent operations greater then or equal to 8. Performance degradation is implemented with the help of SQL SERVER 2000 workload governor.

In SQL SERVER 2000, possible number of concurrent connections are 32,767.

C.OLAP and Data warehousing:

MSDE does not provide OLAP and Data warehousing capabilities.

D.Mail:

MSDE does not have support facility for SQL mail.

E.Administrative Tools:

MSDE doesn't have its own administrative tools. There are many third party tools, which provide administrative capability GUI.

SQL Server have administrative tools such as enterprise manager, Query analyzer or Profiler.

Ref : www.codeproject.com/

How to Filter Window Message in .NET

2009-07-05T14:17:00.010+05:30

Message Filter:

Message filter to prevent specific events from being raised to the control or Forms.

We can achieve the Message Filter through IMessageFilter Interface. It has overridable method name PreMessageFilter.Using this method we can customize our Message Filters.

Example : Filter/Restrict left mouse button down message

public class MyMsgFilter : IMessageFilter
{
public bool PreFilterMessage(ref Message m)
{
// Filter/Restrict left mouse button down message.
if (m.Msg == 513)
{
return true;
}
return false;
}
}

In order to monitor the Message Filter in our application you must register Filter class in your application.

public class mainForm : System.Windows.Forms.Form
{
private MyMsgFilter msgFilter = new MyMsgFilter();
public mainForm()
{
// Add message filter.
Application.AddMessageFilter(msgFilter);
}
}

Following way you can remove your Message Filter
Application.RemoveMessageFilter(msgFilter);

JavaScript document.getElementById

2009-06-21T15:06:00.011+05:30

If you want to quickly access the value of an HTML input give it an id to make your life a lot easier.
This small script below will check to see if there is any text in the text field "myText". The argument that getElementById requires is the id of the HTML element you wish to utilize

function notEmpty()

{

var myTextField = document.getElementById('myText');

if(myTextField.value != "")

alert("You entered: " + myTextField.value)

else

alert("Would you please enter some text?")

}

</script>

Difference between Abstraction and Encapsulation

2009-06-14T19:39:00.003+05:30

Abstraction:

It is virtual class design.
Representation of data that how we represent it.
Before actually defining class developer will think about about the properties, methods and events will be there in class.

Encapsulation:

Hiding of unnecessary data.
At the time of class definition developers will think about which should display to end user and which should not.

Conclusion:
Abstraction is collection of data and Encapsulation is exposure of data in appropriate access specifier.

Difference between Rule and Check Constraint

2009-06-09T21:27:00.006+05:30

Check Constraint:

Check constraint is associated with columns in a Table. So these can't be re-used.

Suppose if "Emp" table having the coulmn "Salary" then
alter table Emp add constraint ck_op Check (Salary between 15000 and 45000)

Rule:

Rules are defined with in a database and can be applied to any number of columns.
Creating Rule:
CREATE RULE SAL_RANGE
as
@Sal > 15000 and @Sal > 45000
Binding Rule to a Column:
SP_BINDRULE 'SAL_RANGE','Emp.Salary'

Encapsulation

2009-05-10T21:42:00.004+05:30

When designing a class, it is generally a good practice to only reveal the necessary interfaces needed to interact with the object, and hide the implementation details that are not precisely relevant. This hiding of details is known as encapsulation.

The concept of encapsulation is better enforced with the definitions of interfaces and implementations. An interface is defined by the services of communication between objects. Classes declare some methods and properties as visible to outside objects, and hide the other details. The visible, or public, methods and properties become the interface to the object. Interfaces typically only include methods, since any need to access an attribute should be made available through a public method.

public class ClsEncapsulation
{
int SqrOutput;
public ClsEncapsulation()
{
}
//Visible method
public void AssignNumber(int GivenNumber)
{
CalculateSqluare(GivenNumber);
}
public void Display()
{
Console.WriteLine("Square of given number is " + SqrOutput.ToString());
}
//Hiding Method
private void CalculateSqluare(int GnNumber)
{
SqrOutput = System.Math.Pow(GnNumber,2);
}

}

Process Vs Thread

2009-05-10T19:41:00.006+05:30

Process:

Process is a heavy weight running instance of a program.
A Process has its own memory space, runtime enivorment and process ID. One process can have multiple threads(It has atleast one main thread).
Processes must use interprocess communication to communicate with silbing processes.
Process is an architectural construct.

Thread:

A thread is the smallest schedulable unit of execution in aWindows application.
A thread always is associated with a particular process.Threads runs the code inside the process and share the address space with other threads inside the process i.e share process handles.
Threads can directly communicate with other threads of its process.
Thread is coding construct.

Assembly Vs Namespace

2009-05-10T09:20:00.000+05:30

Assembly:

An assembly is the primary building block of a .NET Framework application. It is a collection of functionality that is built, versioned, and deployed as a single implementation unit (as one or more files). It's a managed dll or exe (built by .NET).Assemblies are Self-Describing. [e.g. metadata,manifest]
One assembly can contain several namespaces.

Namespace:

A group of managed types (classes, enums, structs, etc). It form the logical boundary for a Group of classes.
One namespace can contain types(Objects) from different assemblies.
The name of the namespace is not necessarily the name of the assembly.

Basics of .NET Namespace

2009-05-10T08:33:00.001+05:30

Namespace are logical grouping of classes and other types such as unions, structures, interfaces and enumerators.

In Microsoft .Net, every program is created with a default namespace. This default namespace is called as global namespace. But the program itself can declare any number of namespaces, each of them with a unique name. The advantage is that every namespace can contain any number of classes, functions, variables and also namespaces etc., whose names are unique only inside the namespace. The members with the same name can be created in some other namespace without any compiler complaints from Microsoft .Net.

If a new project is created in Visual Studio .NET it automatically adds some global namespaces. These namespaces can be different in different projects. But each of them should be placed under the base namespace System.

namespace Books
{
class Authors
{
public void Display()
{
Console.WriteLine("Auther name is Dynamic-Coding");
}
}
This is simple namespace example. We can also build hierarchy of namespace. Here is an example for this.

namespace Books
{
namespace Inventory
{
using System;
class AddInventory
{
public void MyMethod()
{
Console.WriteLine("Adding Inventory via MyMethod!");
}
}
}
}

Let's look how we can use the namespaces in our code

using Books;
class HelloWorld
{
public static void Main()
{
Inventory.AddInventory AddInv = new AddInventory();
AddInv.MyMethod();
}
}

OR

using Books.Inventory;
class HelloWorld
{
public static void Main()
{
AddInventory AddInv = new AddInventory();
AddInv.MyMethod();
}
}

Note:
The namespaces wide opens the doors for 3rd party and project specific custom components and class libraries.

Object filtering using LINQ

2009-05-03T17:43:00.003+05:30

LINQ:
Query is an integrated feature of programming language(like C# and VB.NET).LINQ(Language Integrated query), a set of language extension that allows you to perform queries without leaving the comfort of programming language. It has set of keyword to build a query expression.These query expression can select,filter,sort,group and transform data.

LINQ to Objects:
It is Simplest form of LINQ, allow you to query collection of memory objects. It replace the iteration logic(such as foreach block) with declarative LINQ expression.LINQ using the new set of keywords, including from,in,where and select.

public class Car
{

public Car(string m_Make,string m_Color,int m_Price)
{
Make = m_Make;
Color = m_Color;
Price = m_Price;
}

public string Make { get; set; }
public string Color { get; set; }
public int Price { get; set; }

}

public class LinQApp
{

static void Main(string[] args)
{
ListFiltering();
Console.ReadLine();
}

private static void ListFiltering()
{
List Cars = new List();
Cars.Add(new Car("TATA","Red",100000));
Cars.Add(new Car("TATA", "Yellow", 100000));
Cars.Add(new Car("TATA", "White", 100000));
Cars.Add(new Car("Maruti", "Red", 300000));
Cars.Add(new Car("Maruti", "Yellow", 300000));
//Logic: Show All cars with Red Color
Console.WriteLine("");
//Iterative Method
Console.WriteLine("List Filter Normal Way:");
foreach (Car C in Cars)
{
if (C.Color == "Red")
Console.WriteLine(C.Make + " Price " + C.Price);
}
//LINQ Query Method
Console.WriteLine("");
Console.WriteLine("List Filter LINQ Way:");
IEnumerable MatchCars;

MatchCars = from C in Cars
where C.Color == "Red"
select C; //here C is the object with type of Car

//After the filtering condition all the attributes of car is selected.

foreach (Car MatCar in MatchCars)
{
Console.WriteLine(MatCar.Make + " Price " + MatCar.Price);
}

}

}

Output:

List Filter Normal way:
TATA Price 100000
Maruti Price 300000

List Filter LINQ way:
TATA Price 100000
Maruti Price 300000

PRAGMA AUTONOMOUS_TRANSACTION:To Commit a part of Tranasaction in PL/SQL

2009-05-03T14:14:00.000+05:30

There would be business requirement to just commit or rollback part of the transaction regardless of the actual transactions success or failure.We can handle this using PRAGMA AUTONOMOUS_TRANSACTION, if we create a block as PRAGMA AUTONOMOUS_TRANSACTION then this will be independent of thecalling block so if we Commit or rollback a transaction in this PRAGMA AUTONOMOUS_TRANSACTION block will have no commit/rollback impact on the called block.

Example:
create table pragma_table (ename varchar2(32), e_id number);
insert into pragma_table values ('','1');
insert into pragma_table values ('','2');

CREATE OR REPLACE PROCEDURE Sample_AUTONOMOUS_TRANSACTION(emp_id number)
AS PRAGMA AUTONOMOUS_TRANSACTION;
BEGIN
UPDATE pragma_table SET ename = 'TWO' Where e_id = 2;
dbms_output.put_line('Iyen going to Commit');
COMMIT;
EXCEPTiON WHEN OTHERS THEN
dbms_output.put_line('Iyen in Pragma Exception so rollback' sqlerrm);
ROLLBACK;
END;

BEGIN
UPDATE pragma_table SET ename = 'ONE' Where e_id = 1; Sample_AUTONOMOUS_TRANSACTION(2);exception when others then dbms_output.put_line('Iyen Example in exception' sqlerrm);
end;

Execute the below select once with Commit and once with rollback; You can find the difference.
select * from pragma_table;

RoT: As a Rule of Thumb , always make sure that your Autonomous transaction block is either getting rollback or commit.

Do send your comments.

--Iyen

Overriding Vs Hiding/Shadowing

2009-05-03T14:06:00.000+05:30

Overriding:

An override method provides a new implementation of a member inherited from a base class. The overridden base method must have the same signature as the override method.You cannot override a non-virtual or static method. The overridden base method must be virtual, abstract, or override.
Only a procedure (Function or Sub) or property
Overriding the accessibility is not possible(Base and child class having same access specifiers).
Overriding element inherited by further derived classes; overridden element still overridden.

Hiding(C#)/Shadowing(VB.NET):

When two programming elements share the same name, one of them can hide, or shadow, the other one. In such a situation, the shadowed element is not available for reference.
It applied to any declared element type(procedure (Function or Sub) or property and fields).
Any accessibility is possible.
Shadowing element inherited by further derived classes; shadowed element still hidden.

class BaseClass
{
public int X = 10;
public virtual string overridingMethod()
{
return "BaseClass overridingMethod \n";
}
public string hidingMethod()
{
return "BaseClass hidingMethod \n";
}
public void ParentDisplay()
{
Console.WriteLine("Paerent " + X);
}
}

class DerivedClass : BaseClass
{
public new string X = "Hai"; //Hiding applied even field also(new keyword used for hiding)

public override string overridingMethod()
{
return "DerivedClass overridingMethod \n";
}
internal new string hidingMethod() //Change of accessibility possible in hiding
{
return "DerivedClass hidingMethod \n";
}
public void childDisplay()
{
Console.WriteLine("Child " + X);
}
}

class MainClass
{
static void Main()
{
BaseClass bc = new BaseClass();
Console.WriteLine("Base class ref assigned to Base class object");
bc.ParentDisplay();
Console.Write(bc.overridingMethod());
Console.Write(bc.hidingMethod());
DerivedClass dc = new DerivedClass();
Console.WriteLine("");
Console.WriteLine("Derived class ref assigned to Derived class object");
dc.ParentDisplay();
dc.childDisplay();
Console.Write(dc.overridingMethod());
Console.Write(dc.hidingMethod());
BaseClass bc2 = new DerivedClass();
Console.WriteLine("");
Console.WriteLine("Base class ref assigned to Derived class object");
bc2.ParentDisplay();
Console.Write(bc2.overridingMethod()); //It will return overrided method(not relavent to it's reference)
Console.Write(bc2.hidingMethod()); //It will return method which is relavent to it's reference
}
}

Output :

Base class ref assigned to Base class object
Parent 10
BaseClass overridingMethod
BaseClass hidingMethod

Derived class ref assigned to Derived class object
Parent 10
Child Hai
DerivedClass overridingMethod
DerivedClass hidingMethod

Base class ref assigned to Derived class object
Parent 10
DerivedClass overridingMethod
BaseClass hidingMethod

Reflection in .NET Framework

2009-05-03T13:37:00.001+05:30

Reflection is the feature in .Net, which enables us to get some information about object in runtime. That information contains data of the class. System.Reflection namespace contains all the Reflection related classes. These classes are used to get information from any of the class under .NET framework.

The Type class is the root of all reflection operations. Type is an abstract base class that acts as means to access metadata though the reflection classes. Using Type object, any information related to methods, implementation details and manipulating information can be obtained. The types include the constructors, methods, fields, properties, and events of a class, along with this the module and the assembly in which these information are present can be accessed and manipulated easily.

public class TestDataType
{
public delegate void DelMaxCounterAttained(int Counter);
public event DelMaxCounterAttained MaxCounterAttained;
public TestDataType()
{
counter = 1;
}
public TestDataType(int c)
{
counter = c;
}
public int counter;
public int Inc()
{
if (counter++ >= 10)
MaxCounterAttained(counter);
return counter;
}
public int Dec()
{
return counter--;
}
}

public class ReflectionSample
{
public static void Main()
{
//At first we should get type of object that was created.
TestDataType testObject = new TestDataType(15);
Type objectType = testObject.GetType();

//Using objectType we can able to extract constructor, method and events information
ConstructorInfo[] info = objectType.GetConstructors();
FieldInfo[] fields = objectType.GetFields();
MethodInfo[] methods = objectType.GetMethods();
EventInfo[] events = objectType.GetEvents();

// get all the constructors
Console.WriteLine("Constructors:");
foreach (ConstructorInfo cf in info)
{
Console.WriteLine(cf);
}
Console.WriteLine();

//get all the fields
Console.WriteLine("Fileds:");
foreach (FieldInfo ff in fields)
{
Console.WriteLine(ff);
}

// get all the methods
Console.WriteLine("Methods and handles:");
foreach (MethodInfo mf in methods)
{
Console.WriteLine(mf);
}

//get all the events
Console.WriteLine("Events:");
foreach (EventInfo ef in events)
{
Console.WriteLine(ef);
}

}
}

Output:

Constructors:
Void .ctor()
Void .ctor(Int32)

Fields:
Int32 counter

Methods and hanles:
void add_MaxCounterAttained(DelMaxCounterAttained)
void remove_MaxCounterAttained(DelMaxCounterAttained)
Int32 Inc()
Int32 Dec()
System.String ToString()
Boolean Equals(System.Object)
Int32 GetHashCode()
System.Type GetType()

Events:
DelMaxCounterAttained MaxCounterAttained

Abstract Class Vs Interface

2009-05-03T10:36:00.001+05:30

Abstract Class :

We can not make instance of Abstract Class as well as Interface. It cannot be a sealed class. It can contain abstract methods, abstract property as well as other members (just like normal class).

Interface:

Interface can only contain abstract methods, properties but we don’t need to put abstract and public keyword. All the methods and properties defined in Interface are by default public and abstract. Interface are useful to achieve Multiple inheritence.

abstact class is a abstract view of any realword entity and interface is more abstract one

//Abstract class
public abstract class Calculate
{
public abstract int Result
{
get;
set;
}
public abstract void Summation(int First, int Second);
}

//Interface
public interface ICalculate
{
int Result
{
get;
set;
}
void Summation(int First, int Second);
}

//Abstract class inherited class
public class ClsAbstraction : Calculate
{
private int m_Result;
public override void Summation(int First, int Second)
{
m_Result = First + Second;
}
public override int Result
{
get { return m_Result; }
set { m_Result = value; }
}
}

//Interface implemented class
public class ClsInterface : ICalculate
{
private int m_Result;
public void Summation(int First, int Second)
{
m_Result = First + Second;
}
public int Result
{
get { return m_Result; }
set { m_Result = value; }
}
}

//Main class
public class ClsMain
{
public static void Main()
{
//Using abstarct class
ClsAbstraction objClsAbstarction = new ClsAbstraction();
objClsAbstarction.Summation(4, 5);
Console.WriteLine("Abs class result " + objClsAbstarction.Result);
//Using Interface
ClsInterface ObjClsInterface = new ClsInterface();
ObjClsInterface.Summation(5, 5);
Console.WriteLine("Interface result " + ObjClsInterface.Result);
}
}

Conclusion:

Abstract class having upper-hand in compare to interface. Using interface having only advantage of multiple inheritance.

Difference between String and string data types

2009-05-02T23:03:00.000+05:30

There is no difference between string and String data type. string is C# based keyword and it is alaises for CLR Type(String).

C# defines a number of aliases for CLR types. It have the keywords because they are easier to remember and programmers coming from other languages like c/c++ would also be familiar with these types. They may be used interchangably, and even mixed together,
e.g : string x = new System.String(' ', 5);

These are the aliases defined:

string->System.Strings
byte->System.SByte
byte->System.Byte
short->System.Int16
ushort->System.UInt16
int->System.Int32
uint->System.UInt32
long->System.Int64
ulong->System.UInt64
char->System.Char
float->System.Single
double->System.Double
bool->System.Boolean
decimal->System.Decimal

Boxing and Unboxing in .NET

2009-05-02T22:33:00.001+05:30

Boxing:
Converting a value type to reference type is called Boxing.

Unboxing:
Unboxing is an explicit operation. You have to tell which value type you want to extract from the object.

Int32 vt= 10; //value type variable
object rt= vt; /*memory is allocated on the heap of size equal to size of vt,the value type bits are copied to the newly allocated memory and the address of the object is returned and stored in rt.This is basically called Boxing.*/

Int32 vt2=(Int32)rt;//Unboxing

Purpose of Boxing and UnBoxing :

.NET provides a unified type system. All types including value types derive from the type object. It is possible to call object methods on any value, even values of primitive types such as int.

private void display()
{
Console.WriteLine(3.ToString());
}

calls the object-defined ToString method on an integer value.In programs that need int values to behave like objects, this capability is available on demand. This ability to treat value types as objects bridges the gap between value types and reference types that exists in most languages.

Destructor,Finalizer and Dispose Method in .NET Framework

2009-05-02T19:58:00.001+05:30

Destructor and Finalizer:

Destructor are called by the CLR when the Garbage Collector destroys an object. In VB.NET it is called the Finalize() method. In C# it is declared by putting a tilda '~' in front of the class name (~MyClass() {}). Destructors aren't the best place to put clean up code. This is because it is only called by the GC and you can't determine when it will be called (you can force it to be called, but that's not recommended).

Dispose:

The Dispose() method is simply a method you call manually to clean up yourobject. For this explicit clean up, .NET provides the dispose design pattern. Objects which need explicit clean up of unmanaged resources(connection object,File objects, etc..) implement the IDisposable interface. The IDisposable interface consists of the Dispose method, which unlike the Finalize method is under the control of the developer.

The recommended practice is to implement both Finalize as well as Dispose methods on an object which needs to clean up unmanaged resources. The Finalize method would serve as a backup mechanism in the event that the Dispose is never called. The garbage collector would perform the object finalization and prevent a permanent leak of the unmanaged resource.

Destructor and Forced Garbage Collection in .NET Framework

2009-05-02T18:29:00.001+05:30

Destructor :

In simple terms a destructor is a member that implements the actions required to destruct an instance of a class. The destructors enable the runtime system. Destructor method is called only by .Net frameworks Garbage Collector (GC).

Forced Garbage Collection :

Foced Garbage collection is executed by means of calling System.GC.Collect() method. The garbage collector checks to see if there are any objects in the heap that are no longer being used by the application(checking the references exist for an object).

class Person
{
public Person() //Constructor
{
Console.WriteLine("Person {0} constructor", GetHashCode());
}
~Person() //Destructor
{
Console.WriteLine("Person {0} finalizer", GetHashCode());
}
}

class GCDemo
{
static void Main(string[] args)
{
Person p = new Person(); // The constructor is invoked here.
p = null;
Console.WriteLine("The object p will not be used anymore ");
Person pc = new Person(); // The constructor is invoked here.
pc = null;
Console.WriteLine("The object pc will not be used anymore ");
GC.Collect(); // Force to collect.
Console.WriteLine("Now the carbage collection is called forcefully...");
GC.WaitForPendingFinalizers(); // Wait until it finish
}
}

Output:

Person 33156464 constructor
The object p will not be used anymore
Person 15645912 constructor
The object pc will not be used anymore
Now the carbage collection is called forcefully...
Person 33156464 finalizer
Person 15645912 finalizer

Conclusion:

Destructor methods are called after the garbage collection method executed.
Garbage collector destroys both person objects because reference "p" and "pc" is null.

Step by step process of getting connection string from web.config

2009-05-02T11:22:00.000+05:30

Getting Connection string from web.config
In web.config file you find tag like this

<connectionStrings/>

We have to write a connection in connectionstring tag so that we can use in our application.

Steps are

1.replace <connectionStrings/> by

<connectionStrings>
</connectionStrings>

2.add connection string to this tag
Sql Authentication Connection,you have the user name and passwords of ur database

<add name="ConnectionStringName" connectionString="Data Source=.\Sqlexpress;Initial Catalog=databasename;User ID=databaseuserid;Password=databasepassword" providerName="System.Data.SqlClient"/>

Windows Authentication Connection default settings of Sqlserver2005

<add name="ConnectionStringName" connectionString="Data Source=.\Sqlexpress;Initial Catalog=databasename;integrated security=SSPI" providerName="System.Data.SqlClient"/>

Just u have to replace User ID=databaseuserid;Password=databasepassword to
integrated security=SSPI that’s all for Sql Authentication to Windows Authentication

It look like this

<connectionStrings>
<add name="ConnectionStringName" connectionString="Data Source=.\Sqlexpress;Initial Catalog=databasename;User ID=databaseuserid;Password=databasepassword" providerName="System.Data.SqlClient"/>
</connectionStrings>

or

<connectionStrings>
<add name="ConnectionStringName" connectionString="Data Source=.\Sqlexpress;Initial Catalog=databasename;integrated security=SSPI" providerName="System.Data.SqlClient"/>
</connectionStrings>

3. Getting Connection from web.config using c#

Add fallowing Namespace to your application

using System.Web.Configuration;
using System.Data.SqlClient;

Code for getting connection

SqlConnection sqlConn = null;

String str=
WebConfigurationManager.ConnectionStrings["ConnectionStringName"].ToString();

// Note:Ensure ConnectionStringName is same we mentioned in web.config file that all

sqlConn = new SqlConnection(str);
sqlConn.Open();

// do operation

sqlConn.Close();

Enjoy this coding…

How to change from Windows Authentication to SQL Server Authentication for SQLExpress 2005

2009-04-29T18:21:00.000+05:30

While installing SQL Express, we have to specify Sql Authentication mode and specify password for sa otherwise Windows Authentication mode being enabled (it is a default mode). To change mode we have to perform the following steps to change to SQL Server Authentication, using the sa (system administrator) account

1) Enable SQL Server Authentication by executing: "ALTER LOGIN sa ENABLE", or by using the Microsoft SQL Server Management Studio Express application.

2) Change/set the password for the sa account by executing: "ALTER LOGIN sa WITH PASSWORD = 'yourpassword'"

3) Stop the SQL Server service

4) Open regedit, go to the "HKLMSoftwareMicrosoftMSSqlserverMSSqlServer" entry and set the LoginMode value to 2.

goto start->run-> type regedit
goto search window find LoginMode
it will show in sqlserver entry set LoginMode 2

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL.1\MSSQLServerLoginMode 2

5) Restart the SQL Server service

Email through SMPT Client (ASP.NET/C#)

2009-04-28T19:08:00.000+05:30

Yes,it is easy to send email in .Net application through SMTP Client.First you have add
using System.Net.Mail; namespace should be added in your application.

using System.Net.Mail; //namespace

SmtpClient smtpClient = new SmtpClient("smtp.gmail.com", 587);

System.Net.NetworkCredential mailAuthentication = new System.Net.NetworkCredential("yourmailid@gmail.com", "yourgmailpassword");

MailMessage message = new MailMessage();
try
{
MailAddress fromAddress = new MailAddress("fromemailid@gmail.com"iyen");

// Enable SSL
smtpClient.EnableSsl = true;

smtpClient.UseDefaultCredentials = false;

smtpClient.Credentials = mailAuthentication;

////From address will be given as a MailAddress Object
message.From = fromAddress;
// To address collection of MailAddress
message.To.Add(Togmail@gmail.com);

message.Subject = "Test Mail from C# Application";

message.IsBodyHtml = false;
//// Message body content
message.Body = "Nice C# function"

//// Send SMTP mail
smtpClient.Send(message);
MessageBox.Show("Email successfully sent.");
}
catch (Exception ex)
{
MessageBox.Show("Send Email Failed");
}

Before run this program check your are given
Vaild yourmailid@gmail.com , yourgmailpassword and vaild Togmail@gmail.com..

Connection Pooling in .NET

2009-04-27T20:11:00.001+05:30

Acquiring a connection takes a short, but definite amount of time. In web application in which requests are being handled efficiently,connections will be opened and closed endlessly as new requests are processed. In this environment, a small overhead required to establish a connection can become significant and limit the scalability of the system.

One solution is connection pooling. Connection pooling is the practise of keeping a permanent set of open database connections to be shared by the sessions that uses the same data sources. This avoids the need to create and destroy connection all the time.

When client requests the connection by calling Open(), it's served directly fro the available pool, rather than re-created. When the client release the connections by calling Close() or Dispose(), it's not discarded but returned to the pool to serve next request.

You can able to configure connection pool setting in connection strings. Various connection pool settings are as follows

a. Max Pool Size : The maximum number of connections allowed in the pool. If the maximum pool size size has been reached, any further attempts wait until a connection become available.(An error is raised if the connection timeout value elapses before a connection available.)

b. Min Pool Size : The minimum number of connection always retained in the pool(default as 0). This number of connections will be created when the first connection is opened, leading minor delay for the first request.

c. Pooling : When true (the default), the connection is drawn from the appropriate pool or, if necessary, is created and added to the appropriate pool.

d. Connection Life Time : Connections is returned to the pool and its creation time is older than the specified lifetime.

Example of connection string that set a minimum pool size:

string Connectionstring = "Data Source = localHost; Initial Catalog = master; Integrated Security = SSPI; Min Pool Size = 10;Max Pool Size=60";

SqlConnection con = new SQlConnection(Connectionstring);

//Get the connection from the pool( if it exists)
//or create the pool with 10 connections(if it doesn't)
con.Open();

//Return connection to the pool.
con.Close();

Memory Usage Reduces On Application Minimize

2009-04-26T16:58:00.000+05:30

Everseen memory usage of a program go down as soon as it’s minimized. Well how to achieve this programmatically(VB.NET and C#).

Using the anyone of the following API function we can reduce memory usage.
SetProcessWorkingSetSize( GetCurrentProcess(), -1, -1 );
or
EmptyWorkingSet( GetCurrentProcess() );

Sample Code:

C#:
public class MemoryManagement

{

[DllImport("kernel32.dll")]
public static extern bool SetProcessWorkingSetSize( IntPtr proc, int min, int max );

public void ReleaseMemory()
{

GC.Collect() ;
GC.WaitForPendingFinalizers() ;

if(Environment.OSVersion.Platform == PlatformID.Win32NT)
{
SetProcessWorkingSetSize(System.Diagnostics.Process.GetCurrentProcess().Handle, -1, -1) ;
}

}

VB.NET :

public class MemoryManagement

Private Declare Auto Function SetProcessWorkingSetSize Lib "kernel32.dll" (ByVal procHandle As IntPtr, ByVal min As Int32, ByVal max As Int32) As Boolean

Friend Sub ReleaseMemory()

Try

GC.Collect()
GC.WaitForPendingFinalizers()
If Environment.OSVersion.Platform = PlatformID.Win32NT Then
SetProcessWorkingSetSize(System.Diagnostics.Process.GetCurrentProcess().Handle, -1, -1)
End If

Catch

End Try
End Sub

end class

Delete Vs Truncate(SQL Server)

2009-04-22T23:22:00.001+05:30

• Delete table is a logged operation, so the deletion of each row gets logged in the transaction log, which makes it slow.

• Truncate table also deletes all the rows in a table, but it won’t log the deletion of each row, instead it logs the de-allocation of the data pages of the table, which makes it faster. Of course, truncate table cannot be rolled back.

• Truncate table is functionally identical to delete statement with no “where clause” both remove all rows in the table. But truncate table is faster and uses fewer system and transaction log resources than delete.

• Truncate table removes all rows from a table, but the table structure and its columns, constraints, indexes etc., remains as it is.

• In truncate table the counter used by an identity column for new rows is reset to the seed for the column.

• If you want to retain the identity counter, use delete statement instead.

• You cannot use truncate table on a table referenced by a foreign key constraint; instead, use delete statement without a where clause.

• Truncate table cannot activate a trigger(Any trigger created aganist Delete operation).

• Truncate table may not be used on tables participating in an indexed view.

Update Statement Between Two Tables

2009-04-22T21:59:00.000+05:30

"T1" is the table having the fields of id and name. There is another table "T2" having id and PetName with some additional information. Now to update "T1".name with "T2".PetName.
Update query is as follows(condition between two tables),
update T1 set t1.name = T2.PetName
from T2
where T1.id = T2.id

SQL Server - Insert multilingual data in table

2009-04-22T19:51:00.001+05:30

You need the N'' syntax only if the string contains characters which are not inside the default code page.

"Best practice" is to have N'' whenever you insert into an nvarchar or ntext column.
"Unicode string constants that appear in code executed on the server, such as in stored procedures and triggers, must be preceded by the capital letter N. This is true even if the column being referenced is already defined as Unicode. Without the N prefix, the string is converted to the default code page of the database.

This may not recognize certain characters.The requirement to use the N prefix applies toboth string constants that originate on the server and those sent from the client."

Like:
create table mul (lang nvarchar(200))
insert into mul (lang ) values (N'multilingual unicode strings')
insert into mul (lang ) values (N' தமிழ்')
insert into mul (lang ) values (N' 請提供服務的日期進行')

use nVarChar as the column data type.

How to fix SQL Server Error 3154: The backup set holds a backup of a database other than the existing database.

2009-04-21T23:21:00.002+05:30

Fix/Solution:

Use WITH REPLACE while using the RESTORE command.

RESTORE DATABASE abc FROM DISK = 'C:\backup.bak' WITH REPLACE

In this example abc is one database,backup.bak is backup of abc.

How to Recover Suspected Database in SQL Server 2000

2009-04-15T22:15:00.000+05:30

If a database is marked suspect it cannot be accessed and hence nothing can be performed in the database. A database can be marked suspect for one of the following reasons,

a.If one or more database files are not available.
b.If the entire database is not available.
c.If one or more database files are corrupted.
d.If a database resource is being held by the operating system.

In order to recover the suspected database, sysdatabases status is modified in master database.Before you do any changes with system table run the following command to enable adhoc changes to the system tables.

use master

sp_configure allow, 1

reconfigure with override

sp_resetstatus ‘DatabaseName’

After the procedure is run, immediately disable updates to the system tables:

sp_configure 'allow updates', 0

RECONFIGURE WITH OVERRIDE

Then Stop and Restart ALL SQL Server Services.

If the database still goes back into suspect mode, and you can't fix the original problem, and you have no recent backup, then you can get information out of the database by putting it into Emergency Mode. If you do this, extract the data/objects out with DTS and rebuild the database.

The following command to put the database into emergency mode

USE master

sp_configure 'allow updates', 1

RECONFIGURE WITH OVERRIDE

UPDATE master..sysdatabases SET status = 32768 WHERE name = 'DatabaseName'

sp_configure allow, 0

Stop and Restart ALL SQL Server Services.

We are now ready to pull whatever data we can out of the tables in the corrupt database. Remember, some tables may be corrupt, thus you may have to play with various T-SQL statements to get the data out. First try DTS using EnterprisesManager.

These are the steps necessary to export data out of the corrupt database into the new:

a. Create a new production DB, or a temp DB, to have a place to export whatever data we can out of the corrupt db.

b. Start a DTS operation by going into EM and drilling down to “Data Transformation Services” … “Local Packages”.

c. Open a NEW DTS package by right-mouse clicking …

d. When DTS opens, choose “Copy SQL Server Objects Task” from the Connection Icons. Enter in a description like “Export Corrupt Data”. Enter in the SA/pass combination as well as the CORRUPT database from the drop-down.

e. Select the “Destination” Tab. ”. Enter in the SA/pass combination as well as the PRODUCTION database from the drop-down.

f. Select the “Copy” Tab. UNCHECK the “Create destination objects” box. UNCHECK the “Copy all objects” box and then Click on the “Select Objects” Button. This brings up the “Select Objects” screen.

g. CHECK ONLY “Show all tables” like shown above. Then check each table that needs to be exported. If ALL tables need to be export, Click on the “Select All” button. Click OK.

h. Click OK again and we are done creating this task. Now we execute the package by Clicking the green arrow on the menu bar.

REF : http://www.tek-tips.com/

Localize Date and Time through Specific Culture

2009-04-14T21:19:00.001+05:30

The DateTime structure provides methods that allow your applications to perform culture-sensitive operations on a DateTime type. An application can use the DateTimeFormatInfo class to format and display a DateTime type based on culture.

Following sample code displays the date and time in different cultures are as follows,

public void DateFormatDisplay()
{
//To get the Current culture information
Console.WriteLine(Thread.CurrentThread.CurrentCulture);
DateTime dt = DateTime.Now;
// Creates a CultureInfo for English in US.
CultureInfo CulInf = new CultureInfo("en-US");
Console.WriteLine(dt.ToString("d"));
// Creates a CultureInfo for German in Germany.
CulInf = new CultureInfo("de-DE");
Console.WriteLine(dt.ToString("d", CulInf));
// Creates a CultureInfo for English in Great Britan.
CulInf = new CultureInfo("en-GB");
Console.WriteLine(dt.ToString("d", CulInf));
}

If Current date is 14-Apr-2009 then output of above coding are as follows,

en-US
4/14/2009
14.04.2009
14/04/2009

Disable browser "Back" button

2009-04-14T12:31:00.007+05:30

To avoid Back function in browser.
You have to write the javascript in body of the Html coding..
In body tag,you have to specify the current page name. Let us consider below pages a 'Dynamic.html',in this example we mention onunload we specified the javascript to locate the same page.
Save this html page as 'Dynamic.html' and find it how it works.

<html>
<head>
<title>Dyanmic Coding...</title>
</head>
<body onunload="javascript:window.location.replace('Dynamic.html')"> </body>
</html>
we can apply this approach in Transaction page.in other words Next to Login page.

Script use to Scrolling title in browser.

2009-04-14T11:26:00.006+05:30

Script use to Scrolling title in browser.

Place this Javascript inside ur html code,

then u find your title dynamic coding moves from left to right....

Coding.....

<html>

<head>

<title>Dynamic Coding...</title>

<!-- var repeat=0

var title=document.title

var leng=title.length

var start=1

function titlemove()

{

titl= title.substring(0, start)

document.title=titl

start++

if (start==leng+1)

{

start=1

if (repeat==1)

return

}

setTimeout("titlemove()",100)

}

if (document.title)

{

titlemove()

}

</script>

</head>

<body>Dynamic Coding..</body>

</html>