Download 下载文件方法 

 1   public class Download
 2     {
 3 
 4         private static  ILog log = LogManager.GetLogger(typeof(ConfigManager)); //readonly
 5           
 6 
 7         public Download()
 8         {
 9         } 
10        
11         public static bool ResponseFile(string fullPath)
12         {
13             HttpRequest request = HttpContext.Current.Request;
14             HttpResponse response = HttpContext.Current.Response;
15             try
16             {
17                 FileInfo info = new FileInfo(fullPath);
18                 if (info.Exists)
19                 {
20                     string name = info.Name;
21                     string extension = info.Extension;
22                     name = name.Substring(0, name.Length - extension.Length);
23                     while (HttpUtility.UrlEncode(name + extension, Encoding.UTF8).Length > 0x9c)
24                     {
25                         name = name.Substring(0, name.Length - 1);
26                     }
27                     name = HttpUtility.UrlEncode(name + extension, Encoding.UTF8);
28                     response.Clear();
29                     if (info.Length < 1024000)//0xfa000L)
30                     {
31                         response.ContentType = "application/octet-stream";
32                         response.AddHeader("Content-Disposition", "attachment;filename=" + name);
33                         response.WriteFile(info.FullName);
34                     }
35                     else
36                     {
37                         FileStream input = new FileStream(fullPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
38                         BinaryReader reader = new BinaryReader(input);
39                         try
40                         {
41                             long length = input.Length;
42                             long num2 = 0L;
43                             int count = 10240;// 0x2800;
44                             if (request.Headers["Range"] != null)
45                             {
46                                 response.StatusCode = 0xce;
47                                 num2 = Convert.ToInt64(request.Headers["Range"].Split(new char[] { '=', '-' })[1]);
48                             }
49                             response.AddHeader("Content-Length", (length - num2).ToString());
50                             if (num2 != 0L)
51                             {
52                                 response.AddHeader("Content-Range", string.Format(" bytes {0}-{1}/{2}", num2, length - 1L, length));
53                             }
54                             response.ContentType = "application/octet-stream";
55                             response.AddHeader("Content-Disposition", "attachment;filename=" + name);
56                             reader.BaseStream.Seek(num2, SeekOrigin.Begin);
57                             int num4 = ((int)Math.Floor((double)(((double)(length - num2)) / ((double)count)))) + 1;
58                             for (int i = 0; i < num4; i++)
59                             {
60                                 if (response.IsClientConnected)
61                                 {
62                                     response.BinaryWrite(reader.ReadBytes(count));
63                                     response.Flush();
64                                 }
65                                 else
66                                 {
67                                     i = num4;
68                                 }
69                             }
70                         }
71                         catch
72                         {
73                             return false;
74                         }
75                         finally
76                         {
77                             reader.Close();
78                             input.Close();
79                         }
80                     }
81                 }
82             }
83             catch (Exception exception)
84             {
85                 if (log.IsErrorEnabled)
86                 {
87                     log.Error("", exception);
88                 }
89                 return false;
90             }
91             return true;
92         }
93 
94      }

 

posted on 2016-09-14 15:21  高达  阅读(1334)  评论(0)    收藏  举报

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