asp.net文件下载

 1       protected void btn_Down(object sender, EventArgs e)

 2         {

 3             string filePath = Server.MapPath("/TradeLog/" + txtDate.Text.Trim());

 4             if (!downBeforeValidation(filePath))

 5                 return;

 6             dlZipDir(filePath, txtDate.Text);

 7         }    

 8 

 9        /// <summary>

10         /// 下载前验证

11         /// </summary>

12         /// <param name="filePath">文件路径</param>

13         /// <returns></returns>

14         private bool downBeforeValidation(string filePath)

15         {

16             //判断密码是否正确

17             string downPassWord = WebConfigurationManager.AppSettings["downPassWord"];

18             if (string.IsNullOrEmpty(txtPassWord.Text) || txtPassWord.Text.Trim() != downPassWord)

19             {

20                 Response.Write("<script>alert('密码错误或为空')</script>");

21                 return false;

22             }

23             //判断文件是否存在

24 

25             if (!Directory.Exists(filePath))

26             {

27                 Response.Write("<script>alert('目录不存在')</script>");

28                 return false;

29             }

30             return true;

31         }

32 

33       /// <summary>

34         /// 全部变量

35         /// </summary>

36         ZipOutputStream zos = null;

37         String strBaseDir = "";

38         /// <summary>

39         /// 下载文件

40         /// </summary>

41         /// <param name="strPath">路径</param>

42         /// <param name="strFileName">下载后默认显示文件名称</param>

43         void dlZipDir(string strPath, string strFileName)

44         {

45             MemoryStream ms = null;

46             Response.ContentType = "application/octet-stream";

47             strFileName = HttpUtility.UrlEncode(strFileName).Replace('+', ' ');

48             Response.AddHeader("Content-Disposition", "attachment;   filename=" + strFileName + ".zip");

49             ms = new MemoryStream();

50             zos = new ZipOutputStream(ms);

51             strBaseDir = strPath + "\\";

52             addZipEntry(strBaseDir);

53             zos.Finish();

54             zos.Close();

55             Response.Clear();

56             Response.BinaryWrite(ms.ToArray());

57             Response.End();

58         }

59 

60      /// <summary>

61         /// 生成压缩文件

62         /// </summary>

63         /// <param name="PathStr"></param>

64         void addZipEntry(string PathStr)

65         {

66             DirectoryInfo di = new DirectoryInfo(PathStr);

67             foreach (DirectoryInfo item in di.GetDirectories())

68             {

69                 addZipEntry(item.FullName);

70             }

71             foreach (FileInfo item in di.GetFiles())

72             {

73                 FileStream fs = File.OpenRead(item.FullName);

74                 byte[] buffer = new byte[fs.Length];

75                 fs.Read(buffer, 0, buffer.Length);

76                 string strEntryName = item.FullName.Replace(strBaseDir, "");

77                 ZipEntry entry = new ZipEntry(strEntryName);

78                 zos.PutNextEntry(entry);

79                 zos.Write(buffer, 0, buffer.Length);

80                 fs.Close();

81             }

82         }