文件下载

public void GetDown(String Url)
        {
            string StringFileName = Url.Substring(Url.LastIndexOf("/") + 1);
            string StringFilePath = Request.PhysicalApplicationPath;
            if (!StringFilePath.EndsWith("/")) StringFilePath += "/";
            MSXML2.XMLHTTP _xmlhttp = new MSXML2.XMLHTTPClass();
            _xmlhttp.open("GET", Url, false, null, null);
            _xmlhttp.send("");
            if (_xmlhttp.readyState == 4)
            {
                if (System.IO.File.Exists(StringFilePath + StringFileName))
                    System.IO.File.Delete(StringFilePath + StringFileName);
                System.IO.FileStream fs = new System.IO.FileStream(StringFilePath + StringFileName, System.IO.FileMode.CreateNew);
                System.IO.BinaryWriter w = new System.IO.BinaryWriter(fs);
                w.Write((byte[])_xmlhttp.responseBody);
                w.Close();
                fs.Close();
                Response.Write("文件已经得到。<br><a href='" + Request.ApplicationPath + StringFileName + "' target='_blank'>");
                Response.Write("查看" + StringFileName + "</a>");
            }
            else
                Response.Write(_xmlhttp.statusText);
            Response.End();