i want to export data from gridview to execl but there is execption

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ASP.NET

i want to export data from gridview to execl but

there is execption "RegisterForEventValidation can only be called during Render();"
how to slove this?????

protected void Button3_Click(object sender, EventArgs e)
{   
    ExportGridView2Excel(GridView1, "test.xls");
}

private void ExportGridView2Excel(GridView gridViewControl, string excelFileName)
{
    if (string.IsNullOrEmpty(excelFileName))
        throw new Exception("excelFileName is missing");
    if (!excelFileName.EndsWith(".xls"))
        excelFileName += ".xls";
    gridViewControl.AllowPaging = false;
    gridViewControl.AllowSorting = false;
    StringWriter tw = new StringWriter();
    HtmlTextWriter hw = new HtmlTextWriter(tw);
    Response.Clear();
    Response.ContentType = "application/vnd.ms-excel";
    Response.AddHeader(
        "content-disposition",
        "attachment;filename=" + excelFileName);
    gridViewControl.RenderControl(hw); // execption in this line
    Response.Write(tw.ToString());
    Response.End();
}
public override void VerifyRenderingInServerForm(Control control)
{
    return;
}