How to Expot data Asp.net to Excel

    protected void btnExcel_Click(object sender, EventArgs e)
    {
        try
        {
            Export();
        }
        catch (Exception)
        {
        }
    }
    private void Export()
    {
        Response.Clear();
        Response.AddHeader("content-disposition", "attachment; filename=DepartmentWiseReportOPD.xls");
        Response.Charset = "";
        Response.ContentType = "application/vnd.xls";
        System.IO.StringWriter stringWrite = new System.IO.StringWriter();
        System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);
        dynamicDiv.RenderControl(htmlWrite);
        Response.Write(stringWrite.ToString());
        Response.End();
    }