FileStream MyFileStream;  long FileSize;    MyFileStream = new FileStream=("c:\\a.doc",FileMode.Open);  FileSize = MyFileStream.Length;         byte[] Buffer = new byte[(int)FileSize];  MyFileStream.Read(Buffer, 0, (int)FileSize);  MyFileStream.Close();    Response.AddHeader("Content-Disposition", "attachment;filename="c:\\a.doc");  Response.ContentType="application/octet-stream";   Response.BinaryWrite(Buffer);

 

运行，IE出现打开、下载文件的对话框。但是如果选择直接打开，Word却打不文件。 

试了几次都不行，还以为是2003安全性的问题。 

后来想到ASP.NET缓存，于是加了两行代码 

   Response.Flush(); 

   Response.Close(); 

结果OK。