export data into excel from my form table data.

public static void DownloadExcel(string xlFilePath, string fileName)
{
if (System.IO.File.Exists(xlFilePath))
            {
                Page currentPage = HttpContext.Current.CurrentHandler as Page;
                currentPage.Response.Clear();
                currentPage.Response.Charset = "";
                currentPage.Response.ContentType = "sample.xls";
                currentPage.Response.AddHeader("content-disposition", "attachment;filename=" + fileName);
                byte[] DBuffer;
                using (FileStream objFileStream = new FileStream(xlFilePath, FileMode.Open, FileAccess.Read))
                {
                    DBuffer = new byte[(int)objFileStream.Length];
                    int index = 0;
                    int maxCount = 32767;
                    int remCount = DBuffer.Length;
                    while (index < DBuffer.Length)
                    {
                        if (maxCount > remCount)
                            maxCount = remCount;
                        objFileStream.Read(DBuffer,index,maxCount);
                        index = index + maxCount;
                        remCount = remCount - maxCount;
                    }
                }
                currentPage.Response.Buffer = true;
                currentPage.Response.BinaryWrite(DBuffer);
                currentPage.Response.End();
            }
        }
}