DataTable导出到Excel

        static DataTable GetTable()
        {
            //
            // Here we create a DataTable with four columns.
            //
            DataTable table = new DataTable();
            table.Columns.Add("Dosage", typeof(int));
            table.Columns.Add("Drug", typeof(string));
            table.Columns.Add("Patient", typeof(string));
            table.Columns.Add("Date", typeof(DateTime));

            //
            // Here we add five DataRows.
            //
            table.Rows.Add(25, "Indocin", "David", DateTime.Now);
            table.Rows.Add(50, "Enebrel", "Sam", DateTime.Now);
            table.Rows.Add(10, "Hydralazine", "Christoff", DateTime.Now);
            table.Rows.Add(21, "Combivent", "Janet", DateTime.Now);
            table.Rows.Add(100, "Dilantin", "Melanie", DateTime.Now);
            return table;
        }
        private void ExporttoExcel(DataTable table)
        {
            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.ClearContent();
            HttpContext.Current.Response.ClearHeaders();
            HttpContext.Current.Response.Buffer = true;
            HttpContext.Current.Response.ContentType = "application/ms-excel";
            HttpContext.Current.Response.Write(@"<!DOCTYPE HTML PUBLIC ""-//W3C//DTD HTML 4.0 Transitional//EN"">");
            HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment;filename=Reports.xls");

            HttpContext.Current.Response.Charset = "utf-8";
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("windows-1250");
            //sets font
            HttpContext.Current.Response.Write("<font style='font-size:10.0pt; font-family:Calibri;'>");
            HttpContext.Current.Response.Write("<BR><BR><BR>");
            //sets the table border, cell spacing, border color, font of the text, background, foreground, font height
            HttpContext.Current.Response.Write("<Table border='1' bgColor='#ffffff' " +
              "borderColor='#000000' cellSpacing='0' cellPadding='0' " +
              "style='font-size:10.0pt; font-family:Calibri; background:white;'> <TR>");
            //am getting my grid's column headers
            //int columnscount = GridView_Result.Columns.Count;

            for (int j = 0; j < table.Columns.Count; j++)
            {      //write in new column
                HttpContext.Current.Response.Write("<Td>");
                //Get column headers  and make it as bold in excel columns
                HttpContext.Current.Response.Write("<B>");
                HttpContext.Current.Response.Write(table.Columns[j].ColumnName.ToString());
                HttpContext.Current.Response.Write("</B>");
                HttpContext.Current.Response.Write("</Td>");
            }
            HttpContext.Current.Response.Write("</TR>");
            foreach (DataRow row in table.Rows)
            {//write in new row
                HttpContext.Current.Response.Write("<TR>");
                for (int i = 0; i < table.Columns.Count; i++)
                {
                    HttpContext.Current.Response.Write("<Td>");
                    HttpContext.Current.Response.Write(row[i].ToString());
                    HttpContext.Current.Response.Write("</Td>");
                }

                HttpContext.Current.Response.Write("</TR>");
            }
            //if (table != null)
            //{
            //    foreach (DataColumn dc in table.Columns)
            //    {
            //        Response.Write(dc.ColumnName + "\t");

            //    }
            //    Response.Write(System.Environment.NewLine);

            //    foreach (DataRow dr in table.Rows)
            //    {
            //        for (int i = 0; i < table.Columns.Count; i++)
            //        {
            //            Response.Write(dr[i].ToString() + "\t");
            //        }




            //    }
            //    // range.Columns.AutoFit();
            //    //excel.Visible = true;
            //    //Microsoft.Office.Interop.Excel.Range xlRange = null;
            //    //xlRange = worksheet.get_Range("A1", "T1");
            //    //xlRange.Columns.AutoFit();
            //    //Response.Write("\n");
            //    //Response.End();

            //}
            HttpContext.Current.Response.Write("</Table>");
            HttpContext.Current.Response.Write("</font>");
            HttpContext.Current.Response.Flush();
            HttpContext.Current.Response.End();
        }