Wrtie the following Code in Export button:
protected void btnexport_Click(object sender, EventArgs e)
{
try
{
Response.Clear();
Response.Buffer = true;
Response.AddHeader("content-disposition", "attachment;filename=gridviewdata.xls");
Response.Charset = "";
Response.ContentType = "application/vnd.ms-excel";
StringWriter sWriter = new StringWriter();
HtmlTextWriter hWriter = new HtmlTextWriter(sWriter);
GridView1.RenderControl(hWriter);
Response.Output.Write(sWriter.ToString());
Response.Flush();
Response.End();
}
catch (Exception ex)
{
Label1.Text = ex.ToString();
}
}
//***********
public override void VerifyRenderingInServerForm(Control control)
{
}