asp.net filestream 如何读取pdf文件

<%@ Page  Language="C#"%><%@ Import Namespace="System" %><%@ Import Namespace="System.IO" %><%         Response.Clear();    string path = @"F:\TDDOWNLOAD\Book\C#游戏编程入门.pdf";    Response.ContentType = "application/pdf";    Response.AddHeader("content-disponstion", "filename=C#游戏编程入门.pdf");    byte[] buffer = new byte[256];    FileStream fs = File.Open(path, FileMode.Open);    Response.AddHeader("content-length", fs.Length.ToString());    int length = (int)fs.Length;    if (Response.IsClientConnected)    {        while (length > -1)        {            length = length - buffer.Length;            fs.Read(buffer, 0, buffer.Length);            Response.OutputStream.Write(buffer, 0, buffer.Length);        }    }    fs.Close();    Response.End();       %>