GridView : Export Selected GridView Rows To Excel .(DataTable to Excel)

Below code is used for export selected row from GridView to Excel .Here you can find code for DataTable to Excel.

using System;

using System.Configuration;

using System.Data;

using System.Linq;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.HtmlControls;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Xml.Linq;

using System.Data;

public partial class _Default : System.Web.UI.Page

{

    DataTable dt = new DataTable();

    DataTable dt1 = new DataTable();

    DataRow dr;

    DataRow dr1;

    protected void Page_Load(object sender, EventArgs e)

    {

        if (!Page.IsPostBack)

        {

            BindGrid();

        }

    }

    void BindGrid()

    {

        dt.Columns.Add("eno");

        dt.Columns.Add("empname");

        dt.Columns.Add("sal");

        dr = dt.NewRow();

        dr["eno"] = "101";

        dr["empname"] = "Ravindran";

        dr["sal"] = "45000";

        dt.Rows.Add(dr);

        dr = dt.NewRow();

        dr["eno"] = "102";

        dr["empname"] = "James";

        dr["sal"] = "35000";

        dt.Rows.Add(dr);

        dr = dt.NewRow();

        dr["eno"] = "103";

        dr["empname"] = "Mike";

        dr["sal"] = "20000";

        dt.Rows.Add(dr);

        if (dt.Rows.Count > 0)

        {

            Session["source_table"] = dt;

            GridView1.DataSource = dt;

            GridView1.DataBind();

        }

    }

    //Export all records to excel

    protected void Button1_Click(object sender, EventArgs e)

    {

        //here session value is stored before bind data on gridview

        DataTable dt = Session["source_table"] as DataTable;

        ExportExcel(dt);

    }

    void ExportExcel(DataTable dt)

    {

        Response.ClearContent();

        Response.AddHeader("content-disposition", "attachment; filename=" + DateTime.Now.ToString("ddMMyyyy") + ".xls");

        Response.ContentType = "application/ms-excel";

        string tab = "";

        foreach (DataColumn dc in dt.Columns)

        {

            Response.Write(tab + dc.ColumnName);

            tab = "\t";

        }

        Response.Write("\n");

        int i;

        foreach (DataRow dr in dt.Rows)

        {

            tab = "";

            for (i = 0; i < dt.Columns.Count; i++)

            {

                Response.Write(tab + dr[i].ToString());

                tab = "\t";

            }

            Response.Write("\n");

        }

        Response.End();

    }

    protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)

    {

        if ((e.Row.RowType == DataControlRowType.Header))

        {

            ((CheckBox)e.Row.FindControl("SelectAll")).Attributes.Add("onclick", "javascript:SelectAll('" + ((CheckBox)e.Row.FindControl("SelectAll")).ClientID + "')");

        }

    }

    //Export only selected record

    protected void Button2_Click(object sender, EventArgs e)

    {

        int k = 0;

        //Checkther whether atleast one check box is selected or not

        for (int i = 0; i <= GridView1.Rows.Count - 1; i++)

        {

            GridViewRow row = GridView1.Rows[i];

            CheckBox Ckbox = (CheckBox)row.FindControl("CheckBox1");

            if (Ckbox.Checked == true)

            {

                k++;

            }

        }

        if (k == 0)

        {

            Page.RegisterStartupScript("Alert Message", "");

            return;

        }

        dt1.Columns.Add("eno");

        dt1.Columns.Add("empname");

        dt1.Columns.Add("sal");

        for (int i = 0; i <= GridView1.Rows.Count - 1; i++)

        {

            GridViewRow row = GridView1.Rows[i];

            CheckBox Ckbox = (CheckBox)row.FindControl("CheckBox1");

            if (Ckbox.Checked == true)

            {

                dr1 = dt1.NewRow();

                dr1["eno"] = GridView1.Rows[i].Cells[1].Text;

                dr1["empname"] = GridView1.Rows[i].Cells[2].Text;

                dr1["sal"] = GridView1.Rows[i].Cells[3].Text;

                dt1.Rows.Add(dr1);

            }

        }

        ExportExcel(dt1);

    }

}