Asp.net 2.0 文件下载[支持多线程, 断点续传功能](示例代码下载)

(一) . 概述

最近做了个C/S文件下载工具, 支持多任务, 多线程和断点续传功能. 其中部分代码是从网上找来的, 自己改了

许多Thread Bug, 并增加多任务, 断点续传等功能.

由于公司具有代码所有权, 不能将源代码共享. 自己对比较Asp.net感兴趣, 业余时间自己做了个简单的, 基于

Asp.net 2.0的, 目前能够执行对一个文件的下载任务, 但已经实现了多线程, 断点续传功能. 根据需要您可以增加

多任务 功能, 分享一下, 互相学习! 互相借鉴!

时间仓促, 此程序还没有做很多参数方面的优化. 可以作参考用.

(二).运行效果

";

25

26 DownLoadComponent.HttpWebClient x = new DownLoadComponent.HttpWebClient();

27

28 //注册 DataReceive　事件

29 x.DataReceive += new DownLoadComponent.HttpWebClient.DataReceiveEventHandler(this.x_DataReceive);

30 //注册 ExceptionOccurrs　事件

31 x.ExceptionOccurrs += new DownLoadComponent.HttpWebClient.ExceptionEventHandler(this.x_ExceptionOccurrs);

32

33 string Source = this.TextBox1.Text.Trim();

34 string FileName = Source.Substring(Source.LastIndexOf("/") + 1);

35 string Location= System.IO.Path.Combine( this.TextBox2.Text.Trim() , FileName);

36

37 //F: 源服务器文件; _f: 保存路径; 10: 自设定一个文件有几个线程下载.

38 x.DownloadFile(Source,Location , int.Parse(this.TextBox3.Text));

39

40 //Response.Write("正在下载文件");

41 this.btOK.Enabled = false;

42 this.btCancel.Enabled = true;

43 }

44

45 private void x_DataReceive(DownLoadComponent.HttpWebClient Sender, DownLoadComponent.DownLoadEventArgs e)

46 {

47

48 string f = e.DownloadState.FileName;

49 if (e.DownloadState.AttachmentName != null)

50 f = System.IO.Path.GetDirectoryName(f) + @"\" + e.DownloadState.AttachmentName;

51

52 using (System.IO.FileStream sw = new System.IO.FileStream(f, System.IO.FileMode.OpenOrCreate, System.IO.FileAccess.ReadWrite, System.IO.FileShare.ReadWrite))

53 {

54 sw.Position = e.DownloadState.Position;

55 sw.Write(e.DownloadState.Data, 0, e.DownloadState.Data.Length);

56 sw.Close();

57 }

58 }

59

60 private void x_ExceptionOccurrs(DownLoadComponent.HttpWebClient Sender, DownLoadComponent.ExceptionEventArgs e)

61 {

62 System.Console.WriteLine(e.Exception.Message);

63 //发生异常重新下载相当于断点续传,你可以自己自行选择处理方式或自行处理

64 DownLoadComponent.HttpWebClient x = new DownLoadComponent.HttpWebClient();

65 x.DataReceive += new DownLoadComponent.HttpWebClient.DataReceiveEventHandler(this.x_DataReceive);

66 //订阅 ExceptionOccurrs　事件

67 //x.ExceptionOccurrs += new DownLoadComponent.HttpWebClient.ExceptionEventHandler(this.x_ExceptionOccurrs);

68

69 x.DownloadFileChunk(e.DownloadState.RequestURL, e.DownloadState.FileName, e.DownloadState.Position, e.DownloadState.Length);

70 e.ExceptionAction = DownLoadComponent.ExceptionActions.Ignore;

71 }

72 protected void btCancel_Click(object sender, EventArgs e)

73 {

74 if (DownLoadComponent.HttpWebClient.threads != null)

75 {

76 foreach (Thread t in DownLoadComponent.HttpWebClient.threads)

77 {

78 if (t.IsAlive)

79 {

80 t.Abort();

81 }

82 }

83

84 DownLoadComponent.HttpWebClient.threads.Clear();

85 }

86 System.Diagnostics.Process myproc = new System.Diagnostics.Process();

87 Process[] procs = (Process[])Process.GetProcessesByName("DW20.exe"); //得到所有打开的进程

88 try

89 {

90 foreach (Process proc in procs)

91 {

92 if (proc.CloseMainWindow() == false)

93 {

94 proc.Kill();

95 }

96 }

97 }

98 catch

99 { }

100 KillAllThreads();

101 this.btOK.Enabled = true;

102 this.btCancel.Enabled = false;

103 GC.Collect();

104

105 }

106

107 /// <summary>

108 /// 定期检查控制文件

109 /// </summary>

110 /// <param name="str"></param>

111 /// <returns>是否还继续监视(1: 正在下载中，继续监视; 0: 表示已经下载完毕,不用再检视)</returns>

112 [AjaxMethod()]// or [AjaxPro.AjaxMethod]

113 public bool CheckControlFiles(string strObjPath)

114 {

115 if (!WhetherDownloadFinished(strObjPath))

116 {

117 return true;

118 }

119 return false;

120 }

121

122 private bool WhetherDownloadFinished(string strObjPath)

123 {

124 DirectoryInfo df = new DirectoryInfo(strObjPath);

125 FileInfo[] fi = (FileInfo[])df.GetFiles("*.txt", SearchOption.TopDirectoryOnly);

126 HttpWebClient hwc = new HttpWebClient();

127 for (int i = 0; i < fi.Length; i++)

128 {

129 if (fi[i].FullName.Length > 12 && fi[i].FullName.Substring(fi[i].FullName.Length - 12) == "_Control.txt")

130 {

131 if (hwc.JudgeControlFileIfFinished(fi[i].FullName) == true)

132 {

133 hwc.DeleteControlFile(fi[i].FullName);

134 KillAllThreads();

135 return true;

136 }

137 }

138 }

139 return false;

140 }

141

142 private void KillAllThreads()

143 {

144 foreach (Thread t in HttpWebClient.threads)

145 {

146 if (t.IsAlive)

147 {

148 t.Abort();

149 }

150 }

151 HttpWebClient.threads.Clear();

152 }

153

154 }

155

(四).示例代码下载

http://files.cnblogs.com/MVP33650/MultiThreadDownLoadFile.rar

(五).Asp.net 2.0其它相关文章:

http://blog.csdn.net/ChengKing/category/288694.aspx