ASP.NET 文件下载代码

 1 public static void DownLoad(Page page, string FileName)
 2        {
 3            try
 4            {
 5                System.IO.FileStream r = new System.IO.FileStream(FileName, System.IO.FileMode.Open);
 6                //设置基本信息
 7                page.Response.Buffer = false;
 8                page.Response.AddHeader("Connection", "Keep-Alive");
 9                page.Response.ContentType = "application/octet-stream";
10                page.Response.AddHeader("Content-Disposition", "attachment;filename=" + System.IO.Path.GetFileName(FileName));
11                page.Response.AddHeader("Content-Length", r.Length.ToString());
12                while (true)
13                {
14                    //开辟缓冲区空间
15                    byte[] buffer = new byte[1024];
16                    //读取文件的数据
17                    int leng = r.Read(buffer, 0, 1024);
18                    if (leng == 0)//到文件尾，结束
19                        break;
20                    if (leng == 1024)//读出的文件数据长度等于缓冲区长度，直接将缓冲区数据写入
21                        page.Response.BinaryWrite(buffer);
22                    else
23                    {
24                        //读出文件数据比缓冲区小，重新定义缓冲区大小，只用于读取文件的最后一个数据块
25                        byte[] b = new byte[leng];
26                        for (int i = 0; i < leng; i++)
27                            b[i] = buffer[i];
28                        page.Response.BinaryWrite(b);
29                        break;
30                    }
31                }
32                r.Close();//关闭下载文件
33                HttpContext.Current.ApplicationInstance.CompleteRequest();//结束文件下载
34                page.Response.Flush();
35                page.Response.Close();
36            }
37            catch (System.Exception ex)
38            {
39                throw ex;
40            }
41        }