把GridView導出到Excel

 

       /// <summary>
        /// 導出Excel系統
        /// </summary>
        /// <param name="fileName"></param>
        /// <param name="gv"></param>
        public static void Export(this Page thispage,string fileName, GridView gv)
        {
            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.Charset = "GB2312";
            HttpContext.Current.Response.Buffer = true;
            thispage.EnableViewState = false;
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.Default;
            HttpContext.Current.Response.AddHeader("content-disposition", string.Format("attachment; filename="+ System.Web.HttpUtility.UrlEncode(fileName +".xls", Encoding.UTF8)));
            HttpContext.Current.Response.ContentType = "application/ms-excel";

            using (StringWriter sw = new StringWriter())
            {
                using (HtmlTextWriter htw = new HtmlTextWriter(sw))
                {
                    //  Create a form to contain the grid
                    Table table = new Table();

                    //  add the header row to the table
                    if (gv.HeaderRow != null)
                    {
                        DownExcel.PrepareControlForExport(gv.HeaderRow);
                        table.Rows.Add(gv.HeaderRow);
                    }

                    //  add each of the data rows to the table
                    foreach (GridViewRow row in gv.Rows)
                    {
                        DownExcel.PrepareControlForExport(row);
                        table.Rows.Add(row);
                    }

                    //  add the footer row to the table
                    if (gv.FooterRow != null)
                    {
                        DownExcel.PrepareControlForExport(gv.FooterRow);
                        table.Rows.Add(gv.FooterRow);
                    }

                    //  render the table into the htmlwriter
                    table.RenderControl(htw);

                    //  render the htmlwriter into the response
                    HttpContext.Current.Response.Write(sw.ToString());
                    HttpContext.Current.Response.End();
                }
            }
        }

        /// <summary>
        /// Replace any of the contained controls with literals
        /// </summary>
        /// <param name="control"></param>
        private static void PrepareControlForExport(Control control)
        {
            for (int i = 0; i < control.Controls.Count; i++)
            {
                Control current = control.Controls[i];
                if (current is LinkButton)
                {
                    control.Controls.Remove(current);
                    control.Controls.AddAt(i, new LiteralControl((current as LinkButton).Text));
                }
                else if (current is ImageButton)
                {
                    control.Controls.Remove(current);
                    control.Controls.AddAt(i, new LiteralControl((current as ImageButton).AlternateText));
                }
                else if (current is HyperLink)
                {
                    control.Controls.Remove(current);
                    control.Controls.AddAt(i, new LiteralControl((current as HyperLink).Text));
                }
                else if (current is DropDownList)
                {
                    control.Controls.Remove(current);
                    control.Controls.AddAt(i, new LiteralControl((current as DropDownList).SelectedItem.Text));
                }
                else if (current is System.Web.UI.WebControls.CheckBox)
                {
                    control.Controls.Remove(current);
                    control.Controls.AddAt(i, new LiteralControl((current as System.Web.UI.WebControls.CheckBox).Checked ? "True" : "False"));
                }

                if (current.HasControls())
                {
                    DownExcel.PrepareControlForExport(current);
                }
            }
        }