这里主要实现从服务器到浏览器，推送文件，提供用户下载/浏览的功能。
提示： 在AJAX UpdatePanel里面将无效。如果代码从按钮单击事件中被调用，该按钮需要在 AJAX UpdatePanel的外部。
具体代码如下：
/// <summary> /// Downloads (pushes) file to the client browser. /// **** NOTE **** Cannot be done from inside an AJAX UpdatePanel control. /// </summary> /// <param>The full file path of the file</param> protected void DownloadFile(string fullFilePath) { // Gets the File Name string fileName = fullFilePath.Substring(fullFilePath.LastIndexOf('\\') + 1); byte[] buffer; using (FileStream fileStream = new FileStream(fullFilePath, FileMode.Open)) { int fileSize = (int)fileStream.Length; buffer = new byte[fileSize]; // Read file into buffer fileStream.Read(buffer, 0, (int)fileSize); } Response.Clear(); Response.Buffer = true; Response.BufferOutput = true; Response.ContentType = "application/x-download"; Response.AddHeader("Content-Disposition", "attachment; filename=" + fileName); Response.CacheControl = "public"; // writes buffer to OutputStream Response.OutputStream.Write(buffer, 0, buffer.Length); Response.End(); }