学步园

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace AIS.Web
{
    /// <summary>
    /// 把GridView作为文件下载，可供Excel打开
    /// </summary>
    public class DataGridToFile
    {
        public DataGridToFile()
        {}

        public static void Download(DataGrid dg)
        {
            Download(dg, "report_" + DateTime.Now.ToString("yyyyMMdd") +".xls" );
        }

        public static void Download(DataGrid dg, string fileName)
        {
            TranComplexCtlToLiteral(dg);

            System.IO.StringWriter sw = new System.IO.StringWriter();
            HtmlTextWriter htw=new HtmlTextWriter(sw);
            dg.RenderControl(htw);

            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.Buffer=false;
            HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename="+fileName); 
            HttpContext.Current.Response.ContentType = "application/excel"; 
            HttpContext.Current.Response.Charset="GB2312";
            HttpContext.Current.Response.ContentEncoding=System.Text.Encoding.GetEncoding("GB2312"); 
            HttpContext.Current.Response.Write(sw.ToString()); 
            HttpContext.Current.Response.End(); 
        }

        /// <summary>
        /// 把复杂控件都变为只显示文字的控件
        /// </summary>
        private static void TranComplexCtlToLiteral(WebControl ctl)
        {
            if(ctl==null) return;
            if(ctl.HasControls()==false) return;

            for(int i =0; i < ctl.Controls.Count; i++)
            {
                Literal l=new Literal();
                WebControl curChild=ctl.Controls[i] as WebControl;

                if(curChild is HyperLink)
                {
                    HyperLink hl=curChild as HyperLink;
                    l.Text = hl.Text;
                    ctl.Controls.Remove(curChild);
                    ctl.Controls.AddAt(i,l);
                }
                else if(curChild is DropDownList)
                {
                    DropDownList ddl=curChild as DropDownList;
                    l.Text=ddl.SelectedItem.Text;
                    ctl.Controls.Remove(curChild);
                    ctl.Controls.AddAt(i,l);
                }
                TranComplexCtlToLiteral(curChild);
            }
        }
    }
}