asp.net 下载图片

[csharp] 
//引用 
using System.IO;   
 
 
//button事件 
protected void Button3_Click(object sender, EventArgs e) 
    { 
        string fileName = "123.jpg";//客户端保存的文件名 
        string filePath = Server.MapPath("images/1.jpg");//路径 
        //以字符流的形式下载文件 
        FileStream fs = new FileStream(filePath, FileMode.Open); 
        byte[] bytes = new byte[(int)fs.Length]; 
        fs.Read(bytes, 0, bytes.Length); 
        fs.Close(); 
        Response.ContentType = "application/octet-stream"; 
        //通知浏览器下载文件而不是打开 
        Response.AddHeader("Content-Disposition", "attachment;  filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8)); 
        Response.BinaryWrite(bytes); 
        Response.Flush(); 
        Response.End(); 
 
 
    }