asp.net 导出word excel 当前上下文中不存在名称“Encoding”报错问题

======web页面=============

using System.IO;

using System.Data.OleDb;

using System.Text;

using ......

//excel导出

protected void ExcelExprot_ServerClick(object sender, ImageClickEventArgs e)

private void Export(string FileType, string FileName)

//如果没有下面方法会报错类型“GridView”的控件“GridView1”必须放在具有 runat=server 的窗体标记内

public override void VerifyRenderingInServerForm(System.Web.UI.Control control)

//导出到word

protected void WordExport_ServerClick(object sender, ImageClickEventArgs e)

{

Response.Clear();

Response.Buffer = true;

Response.Charset = "GB2312";

//filename 输出的文件名是什么？

Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode("低耗标准库.doc", Encoding.UTF8).ToString());

Response.ContentEncoding = System.Text.Encoding.UTF7;

Response.ContentType = "application/ms-word";//设置输出文件类型为word文件。

System.IO.StringWriter oStringWriter = new System.IO.StringWriter();

System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);

this.GVCheapMaterialLib.RenderControl(oHtmlTextWriter);

Response.Output.Write(oStringWriter.ToString());

Response.Flush();

Response.End();

}