网页中的ContentType 文件下载

服务器送给客户端的数据包类型可以是text/html文本，也可以是gif/jpeg图形文件，所以每次传输前，我们都必须告知客户端将要传输的文件类型，一般默认情况下为“Text/Html”类型。

一下是文件下载的demo:

Stream responseStream = spFile.OpenBinaryStream();
                HttpContext.Current.Response.Clear();
                HttpContext.Current.Response.AddHeader("content-disposition", "attachment;filename=" + spFile.Name);
                HttpContext.Current.Response.ContentType = "application/octet-stream";
                HttpContext.Current.Response.Buffer = true;


                int streamPosition = 1;
                byte[] inBuf = new Byte[1024];
                while (streamPosition > 0)
                {
                    streamPosition = responseStream.Read(inBuf, 0, inBuf.Length);
                    HttpContext.Current.Response.OutputStream.Write(inBuf, 0, streamPosition);
                    HttpContext.Current.Response.Flush();
                }

                responseStream.Close();

参考：

http://msdn.microsoft.com/en-us/library/ms775147.aspx#_replace

http://www.qihangnet.com/PermaLink,guid,d19bc568-38be-40cd-94fc-881e0ba7ce42.aspx