ASP. NET File Download Code

1   Public   Static   Void Download (page, String Filename)
2 {
3 Try
4 {
5 System. Io. filestream R =   New System. Io. filestream (filename, system. Io. filemode. Open );
6 // Set Basic Information
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 // Buffer space opening
15 Byte [] Buffer =   New   Byte [ 1024 ];
16 // Read File data
17 Int Leng = R. Read (buffer, 0 , 1024 );
18 If (Leng =   0 ) // End at the end of the file
19 Break ;
20 If (Leng =   1024 ) // The read file data length is equal to the buffer length, and the buffer data is directly written
21 Page. response. binarywrite (buffer );
22 Else
23 {
24 // Reading file data is smaller than the buffer, and the buffer size is redefined. It is only used to read the last data block of the file.
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 (); // Close File Download
33 Httpcontext. Current. applicationinstance. completerequest (); // End File Download
34 Page. response. Flush ();
35 Page. response. Close ();
36 }
37 Catch (System. Exception ex)
38 {
39ThrowEx;
40}
41 }