GridView 导出多种文件

 using System;
using System.Collections.Generic;
using System.Text;
using System.Data;

using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Text.RegularExpressions;

namespace Dealeasy.ExportDataSet
{
    public class ExportDataSet
    {
          /// <summary>
          /// 导出DataSet到客户端
          /// </summary>
          /// <param name="dsResults">源DataSet</param>
          /// <param name="enExport">导出类型</param>
          /// <param name="strColDelim">列字符</param>
          /// <param name="strRowDelim">行字符</param>
          /// <param name="strFileName">导出文件名</param>
          public static  void WebExportDataSet(DataSet dsResults , ExportFormat enExport,string strColDelim, string strRowDelim, string strFileName)
         {
             GridView dgExport = new GridView();
             //DataGrid dgExport = new DataGrid();       
             dgExport.AllowPaging =false;
             dgExport.DataSource =dsResults;
             dsResults.DataSetName ="NewDataSet";
             dgExport.DataMember =  dsResults.Tables[0].TableName;
             dgExport.DataBind();           
             System.Web.HttpContext.Current.Response.Clear();           
             System.Web.HttpContext.Current.Response.Buffer= true;
             System.Web.HttpContext.Current.Response.ContentEncoding = Encoding.GetEncoding("gb2312");
             System.Web.HttpContext.Current.Response.Charset = "";
             System.Web.HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=" +strFileName );
             switch(enExport.ToString().ToLower())
             {
                 case "xls":
                 {
                     System.Web.HttpContext.Current.Response.ContentType = "application/vnd.ms-excel";                                       
                     System.IO.StringWriter oStringWriter = new System.IO.StringWriter();                                       
                     System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
                     dgExport.RenderControl(oHtmlTextWriter);
                     System.Web.HttpContext.Current.Response.Write(oStringWriter.ToString());
                     break;
                 }
                 case "custom":
                 {
                     string strText;                           
                     System.Web.HttpContext.Current.Response.ContentType = "text/txt";                                                   
                     System.IO.StringWriter oStringWriter = new System.IO.StringWriter();                   
                     System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);                   
                     dgExport.RenderControl(oHtmlTextWriter);
                     strText = oStringWriter.ToString();                   
                     strText = ParseToDelim(strText ,strRowDelim,strColDelim);
                     System.Web.HttpContext.Current.Response.Write(strText);
                    
                     break;
                 }
                 case "csv":
                 {
                     string strText;       
                     strRowDelim = System.Environment.NewLine;
                     strColDelim = ",";
                     System.Web.HttpContext.Current.Response.ContentType = "text/txt";
                     System.IO.StringWriter oStringWriter = new System.IO.StringWriter();                   
                     System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);                                       
                     dgExport.RenderControl(oHtmlTextWriter);
                     strText = oStringWriter.ToString();                   
                     strText = ParseToDelim(strText ,strRowDelim,strColDelim);
                     System.Web.HttpContext.Current.Response.Write(strText);
                     break;
                 }           
                 case "tsv":
                 {
                     string strText;       
                     strRowDelim = System.Environment.NewLine;
                     strColDelim = "/t";
                     System.Web.HttpContext.Current.Response.ContentType = "text/txt";                                                   
                     System.IO.StringWriter oStringWriter = new System.IO.StringWriter();                   
                     System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);                                       
                     dgExport.RenderControl(oHtmlTextWriter);
                     strText = oStringWriter.ToString();                   
                     strText = ParseToDelim(strText ,strRowDelim,strColDelim);
                     System.Web.HttpContext.Current.Response.Write(strText);
                     break;
                 }
                 case "xml":
                 {
                     System.Web.HttpContext.Current.Response.ContentType = "text/xml";                   
                     System.Web.HttpContext.Current.Response.Write(dsResults.GetXml());                                       
                     break;
                 }
                 case "htm":
                 {                   
                     System.Web.HttpContext.Current.Response.ContentType = "text/html";
                     System.IO.StringWriter oStringWriter = new System.IO.StringWriter();                   
                     System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
                     dgExport.RenderControl(oHtmlTextWriter);                   
                     System.Web.HttpContext.Current.Response.Write(oStringWriter.ToString());                   
                     break;
                 }
             }
             System.Web.HttpContext.Current.Response.End ();
         }
 
         //"Export To a Delim Format"
         #region "Export To a Delim Format"
         private static string ParseToDelim(string strText, string  strRowDelim , string strColDelim)
         {
             Regex objReg = new Regex(@"(>/s+<)",RegexOptions.IgnoreCase);                   
             strText = objReg.Replace(strText,"><");
             strText = strText.Replace(System.Environment.NewLine,"");
             strText = strText.Replace("</td></tr><tr><td>",strRowDelim);
            strText = strText.Replace("</td><td>",strColDelim);
            objReg = new Regex(@"<[^>]*>",RegexOptions.IgnoreCase);                   
            strText = objReg.Replace(strText,"");               
            strText = System.Web.HttpUtility.HtmlDecode(strText);
            return strText;
        }
        #endregion
    }

       
    public enum ExportFormat
    {
        XML,
        XLS,
        HTML,
        CSV,
        CUSTOM,
        TSV   
    }
}