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代码如下

/* .Net/C#: 实现支持断点续传多线程下载的 Http Web 客户端工具类 (C# DIY HttpWebClient)  * Reflector 了一下 System.Net.WebClient ,改写或增加了若干:  * DownLoad、Upload 相关方法!  * DownLoad 相关改动较大!  * 增加了 DataReceive、ExceptionOccurrs 事件!  * 了解服务器端与客户端交互的 HTTP 协议参阅:  * 使文件下载的自定义连接支持 FlashGet 的断点续传多线程链接下载! JSP/Servlet 实现!  * http://blog.csdn.net/playyuer/archive/2004/08/02/58430.aspx  * 使文件下载的自定义连接支持 FlashGet 的断点续传多线程链接下载! C#/ASP.Net 实现!  * http://blog.csdn.net/playyuer/archive/2004/08/02/58281.aspx  */  //2005-03-14 修订:  /* .Net/C#: 实现支持断点续传多线程下载的工具类  * Reflector 了一下 System.Net.WebClient ,改写或增加了若干:  * DownLoad、Upload 相关方法!  * 增加了 DataReceive、ExceptionOccurrs　事件  */  namespace Microshaoft.Utils  {  using System;  using System.IO;  using System.Net;  using System.Text;  using System.Security;  using System.Threading;  using System.Collections.Specialized;  /// <summary>  /// 记录下载的字节位置  /// </summary>  public class DownLoadState  {  private string _FileName;  private string _AttachmentName;  private int _Position;  private string _RequestURL;  private string _ResponseURL;  private int _Length;  private byte[] _Data;  public string FileName  {  get  {  return _FileName;  }  }  public int Position  {  get  {  return _Position;  }  }  public int Length  {  get  {  return _Length;  }  }  public string AttachmentName  {  get  {  return _AttachmentName;  }  }  public string RequestURL  {  get  {  return _RequestURL;  }  }  public string ResponseURL  {  get  {  return _ResponseURL;  }  }  public byte[] Data  {  get  {  return _Data;  }  }  internal DownLoadState(string RequestURL, string ResponseURL, string FileName, string AttachmentName, int Position, int Length, byte[] Data)  {  this._FileName = FileName;  this._RequestURL = RequestURL;  this._ResponseURL = ResponseURL;  this._AttachmentName = AttachmentName;  this._Position = Position;  this._Data = Data;  this._Length = Length;  }  internal DownLoadState(string RequestURL, string ResponseURL, string FileName, string AttachmentName, int Position, int Length, ThreadCallbackHandler tch)  {  this._RequestURL = RequestURL;  this._ResponseURL = ResponseURL;  this._FileName = FileName;  this._AttachmentName = AttachmentName;  this._Position = Position;  this._Length = Length;  this._ThreadCallback = tch;  }  internal DownLoadState(string RequestURL, string ResponseURL, string FileName, string AttachmentName, int Position, int Length)  {  this._RequestURL = RequestURL;  this._ResponseURL = ResponseURL;  this._FileName = FileName;  this._AttachmentName = AttachmentName;  this._Position = Position;  this._Length = Length;  }  private ThreadCallbackHandler _ThreadCallback;  public HttpWebClient httpWebClient  {  get  {  return this._hwc;  }  set  {  this._hwc = value;  }  }  internal Thread thread  {  get  {  return _thread;  }  set  {  _thread = value;  }  }  private HttpWebClient _hwc;  private Thread _thread;  //  internal void StartDownloadFileChunk()  {  if (this._ThreadCallback != null)  {  this._ThreadCallback(this._RequestURL, this._FileName, this._Position, this._Length);  this._hwc.OnThreadProcess(this._thread);  }  }  }  //委托代理线程的所执行的方法签名一致  public delegate void ThreadCallbackHandler(string S, string s, int I, int i);  //异常处理动作  public enum ExceptionActions  {  Throw,  CancelAll,  Ignore,  Retry  }  /// <summary>  /// 包含 Exception 事件数据的类  /// </summary>  public class ExceptionEventArgs : System.EventArgs  {  private System.Exception _Exception;  private ExceptionActions _ExceptionAction;  private DownLoadState _DownloadState;  public DownLoadState DownloadState  {  get  {  return _DownloadState;  }  }  public Exception Exception  {  get  {  return _Exception;  }  }  public ExceptionActions ExceptionAction  {  get  {  return _ExceptionAction;  }  set  {  _ExceptionAction = value;  }  }  internal ExceptionEventArgs(System.Exception e, DownLoadState DownloadState)  {  this._Exception = e;  this._DownloadState = DownloadState;  }  }  /// <summary>  /// 包含 DownLoad 事件数据的类  /// </summary>  public class DownLoadEventArgs : System.EventArgs  {  private DownLoadState _DownloadState;  public DownLoadState DownloadState  {  get  {  return _DownloadState;  }  }  public DownLoadEventArgs(DownLoadState DownloadState)  {  this._DownloadState = DownloadState;  }  }  public class ThreadProcessEventArgs : System.EventArgs  {  private Thread _thread;  public Thread thread  {  get  {  return this._thread;  }  }  public ThreadProcessEventArgs(Thread thread)  {  this._thread = thread;  }  }  /// <summary>  /// 支持断点续传多线程下载的类  /// </summary>  public class HttpWebClient  {  private static object _SyncLockObject = new object();  public delegate void DataReceiveEventHandler(HttpWebClient Sender, DownLoadEventArgs e);  public event DataReceiveEventHandler DataReceive; //接收字节数据事件  public delegate void ExceptionEventHandler(HttpWebClient Sender, ExceptionEventArgs e);  public event ExceptionEventHandler ExceptionOccurrs; //发生异常事件  public delegate void ThreadProcessEventHandler(HttpWebClient Sender, ThreadProcessEventArgs e);  public event ThreadProcessEventHandler ThreadProcessEnd; //发生多线程处理完毕事件  private int _FileLength; //下载文件的总大小  public int FileLength  {  get  {  return _FileLength;  }  }  /// <summary>  /// 分块下载文件  /// </summary>  /// <param name="Address">URL 地址</param>  /// <param name="FileName">保存到本地的路径文件名</param>  /// <param name="ChunksCount">块数,线程数</param>  public void DownloadFile(string Address, string FileName, int ChunksCount)  {  int p = 0; // position  int s = 0; // chunk size  string a = null;  HttpWebRequest hwrq;  HttpWebResponse hwrp = null;  try  {  hwrq = (HttpWebRequest) WebRequest.Create(this.GetUri(Address));  hwrp = (HttpWebResponse) hwrq.GetResponse();  long L = hwrp.ContentLength;  hwrq.Credentials = this.m_credentials;  L = ((L == -1) || (L > 0x7fffffff)) ? ((long) 0x7fffffff) : L; //Int32.MaxValue 该常数的值为 2,147,483,647; 即十六进制的 0x7FFFFFFF  int l = (int) L;  this._FileLength = l;  // 在本地预定空间(竟然在多线程下不用先预定空间)  // FileStream sw = new FileStream(FileName, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite);  // sw.Write(new byte[l], 0, l);  // sw.Close();  // sw = null;  bool b = (hwrp.Headers["Accept-Ranges"] != null & hwrp.Headers["Accept-Ranges"] == "bytes");  a = hwrp.Headers["Content-Disposition"]; //attachment  if (a != null)  {  a = a.Substring(a.LastIndexOf("filename=") + 9);  }  else  {  a = FileName;  }  int ss = s;  if (b)  {  s = l / ChunksCount;  if (s < 2 * 64 * 1024) //块大小至少为 128 K 字节  {  s = 2 * 64 * 1024;  }  ss = s;  int i = 0;  while (l > s)  {  l -= s;  if (l < s)  {  s += l;  }  if (i++ > 0)  {  DownLoadState x = new DownLoadState(Address, hwrp.ResponseUri.AbsolutePath, FileName, a, p, s, new ThreadCallbackHandler(this.DownloadFileChunk));  // 单线程下载  // x.StartDownloadFileChunk();  x.httpWebClient = this;  //多线程下载  Thread t = new Thread(new ThreadStart(x.StartDownloadFileChunk));  //this.OnThreadProcess(t);  t.Start();  }  p += s;  }  s = ss;  byte[] buffer = this.ResponseAsBytes(Address, hwrp, s, FileName);  this.OnThreadProcess(Thread.CurrentThread);  // lock (_SyncLockObject)  // {  // this._Bytes += buffer.Length;  // }  }  }  catch (Exception e)  {  ExceptionActions ea = ExceptionActions.Throw;  if (this.ExceptionOccurrs != null)  {  DownLoadState x = new DownLoadState(Address, hwrp.ResponseUri.AbsolutePath, FileName, a, p, s);  ExceptionEventArgs eea = new ExceptionEventArgs(e, x);  ExceptionOccurrs(this, eea);  ea = eea.ExceptionAction;  }  if (ea == ExceptionActions.Throw)  {  if (!(e is WebException) && !(e is SecurityException))  {  throw new WebException("net_webclient", e);  }  throw;  }  }  }  internal void OnThreadProcess(Thread t)  {  if (ThreadProcessEnd != null)  {  ThreadProcessEventArgs tpea = new ThreadProcessEventArgs(t);  ThreadProcessEnd(this, tpea);  }  }  /// <summary>  /// 下载一个文件块,利用该方法可自行实现多线程断点续传  /// </summary>  /// <param name="Address">URL 地址</param>  /// <param name="FileName">保存到本地的路径文件名</param>  /// <param name="Length">块大小</param>  public void DownloadFileChunk(string Address, string FileName, int FromPosition, int Length)  {  HttpWebResponse hwrp = null;  string a = null;  try  {  //this._FileName = FileName;  HttpWebRequest hwrq = (HttpWebRequest) WebRequest.Create(this.GetUri(Address));  //hwrq.Credentials = this.m_credentials;  hwrq.AddRange(FromPosition);  hwrp = (HttpWebResponse) hwrq.GetResponse();  a = hwrp.Headers["Content-Disposition"]; //attachment  if (a != null)  {  a = a.Substring(a.LastIndexOf("filename=") + 9);  }  else  {  a = FileName;  }  byte[] buffer = this.ResponseAsBytes(Address, hwrp, Length, FileName);  // lock (_SyncLockObject)  // {  // this._Bytes += buffer.Length;  // }  }  catch (Exception e)  {  ExceptionActions ea = ExceptionActions.Throw;  if (this.ExceptionOccurrs != null)  {  DownLoadState x = new DownLoadState(Address, hwrp.ResponseUri.AbsolutePath, FileName, a, FromPosition, Length);  ExceptionEventArgs eea = new ExceptionEventArgs(e, x);  ExceptionOccurrs(this, eea);  ea = eea.ExceptionAction;  }  if (ea == ExceptionActions.Throw)  {  if (!(e is WebException) && !(e is SecurityException))  {  throw new WebException("net_webclient", e);  }  throw;  }  }  }  internal byte[] ResponseAsBytes(string RequestURL, WebResponse Response, long Length, string FileName)  {  string a = null; //AttachmentName  int P = 0; //整个文件的位置指针  int num2 = 0;  try  {  a = Response.Headers["Content-Disposition"]; //attachment  if (a != null)  {  a = a.Substring(a.LastIndexOf("filename=") + 9);  }  long num1 = Length; //Response.ContentLength;  bool flag1 = false;  if (num1 == -1)  {  flag1 = true;  num1 = 0x10000; //64k  }  byte[] buffer1 = new byte[(int) num1];  int p = 0; //本块的位置指针  string s = Response.Headers["Content-Range"];  if (s != null)  {  s = s.Replace("bytes ", "");  s = s.Substring(0, s.IndexOf("-"));  P = Convert.ToInt32(s);  }  int num3 = 0;  Stream S = Response.GetResponseStream();  do  {  num2 = S.Read(buffer1, num3, ((int) num1) - num3);  num3 += num2;  if (flag1 && (num3 == num1))  {  num1 += 0x10000;  byte[] buffer2 = new byte[(int) num1];  Buffer.BlockCopy(buffer1, 0, buffer2, 0, num3);  buffer1 = buffer2;  }  // lock (_SyncLockObject)  // {  // this._bytes += num2;  // }  if (num2 > 0)  {  if (this.DataReceive != null)  {  byte[] buffer = new byte[num2];  Buffer.BlockCopy(buffer1, p, buffer, 0, buffer.Length);  DownLoadState dls = new DownLoadState(RequestURL, Response.ResponseUri.AbsolutePath, FileName, a, P, num2, buffer);  DownLoadEventArgs dlea = new DownLoadEventArgs(dls);  //触发事件  this.OnDataReceive(dlea);  //System.Threading.Thread.Sleep(100);  }  p += num2; //本块的位置指针  P += num2; //整个文件的位置指针  }  else  {  break;  }  }  while (num2 != 0);  S.Close();  S = null;  if (flag1)  {  byte[] buffer3 = new byte[num3];  Buffer.BlockCopy(buffer1, 0, buffer3, 0, num3);  buffer1 = buffer3;  }  return buffer1;  }  catch (Exception e)  {  ExceptionActions ea = ExceptionActions.Throw;  if (this.ExceptionOccurrs != null)  {  DownLoadState x = new DownLoadState(RequestURL, Response.ResponseUri.AbsolutePath, FileName, a, P, num2);  ExceptionEventArgs eea = new ExceptionEventArgs(e, x);  ExceptionOccurrs(this, eea);  ea = eea.ExceptionAction;  }  if (ea == ExceptionActions.Throw)  {  if (!(e is WebException) && !(e is SecurityException))  {  throw new WebException("net_webclient", e);  }  throw;  }  return null;  }  }  private void OnDataReceive(DownLoadEventArgs e)  {  //触发数据到达事件  DataReceive(this, e);  }  public byte[] UploadFile(string address, string fileName)  {  return this.UploadFile(address, "POST", fileName, "file");  }  public string UploadFileEx(string address, string method, string fileName, string fieldName)  {  return Encoding.ASCII.GetString(UploadFile(address, method, fileName, fieldName));  }  public byte[] UploadFile(string address, string method, string fileName, string fieldName)  {  byte[] buffer4;  FileStream stream1 = null;  try  {  fileName = Path.GetFullPath(fileName);  string text1 = "---------------------" + DateTime.Now.Ticks.ToString("x");  string text2 = "application/octet-stream";  stream1 = new FileStream(fileName, FileMode.Open, FileAccess.Read);  WebRequest request1 = WebRequest.Create(this.GetUri(address));  request1.Credentials = this.m_credentials;  request1.ContentType = "multipart/form-data; boundary=" + text1;  request1.Method = method;  string[] textArray1 = new string[7] {"--", text1, "\r\nContent-Disposition: form-data; name=\"" + fieldName + "\"; filename=\"", Path.GetFileName(fileName), "\"\r\nContent-Type: ", text2, "\r\n\r\n"};  string text3 = string.Concat(textArray1);  byte[] buffer1 = Encoding.UTF8.GetBytes(text3);  byte[] buffer2 = Encoding.ASCII.GetBytes("\r\n--" + text1 + "\r\n");  long num1 = 0x7fffffffffffffff;  try  {  num1 = stream1.Length;  request1.ContentLength = (num1 + buffer1.Length) + buffer2.Length;  }  catch  {  }  byte[] buffer3 = new byte[Math.Min(0x2000, (int) num1)];  using (Stream stream2 = request1.GetRequestStream())  {  int num2;  stream2.Write(buffer1, 0, buffer1.Length);  do  {  num2 = stream1.Read(buffer3, 0, buffer3.Length);  if (num2 != 0)  {  stream2.Write(buffer3, 0, num2);  }  }  while (num2 != 0);  stream2.Write(buffer2, 0, buffer2.Length);  }  stream1.Close();  stream1 = null;  WebResponse response1 = request1.GetResponse();  buffer4 = this.ResponseAsBytes(response1);  }  catch (Exception exception1)  {  if (stream1 != null)  {  stream1.Close();  stream1 = null;  }  if (!(exception1 is WebException) && !(exception1 is SecurityException))  {  //throw new WebException(SR.GetString("net_webclient"), exception1);  throw new WebException("net_webclient", exception1);  }  throw;  }  return buffer4;  }  private byte[] ResponseAsBytes(WebResponse response)  {  int num2;  long num1 = response.ContentLength;  bool flag1 = false;  if (num1 == -1)  {  flag1 = true;  num1 = 0x10000;  }  byte[] buffer1 = new byte[(int) num1];  Stream stream1 = response.GetResponseStream();  int num3 = 0;  do  {  num2 = stream1.Read(buffer1, num3, ((int) num1) - num3);  num3 += num2;  if (flag1 && (num3 == num1))  {  num1 += 0x10000;  byte[] buffer2 = new byte[(int) num1];  Buffer.BlockCopy(buffer1, 0, buffer2, 0, num3);  buffer1 = buffer2;  }  }  while (num2 != 0);  stream1.Close();  if (flag1)  {  byte[] buffer3 = new byte[num3];  Buffer.BlockCopy(buffer1, 0, buffer3, 0, num3);  buffer1 = buffer3;  }  return buffer1;  }  private NameValueCollection m_requestParameters;  private Uri m_baseAddress;  private ICredentials m_credentials = CredentialCache.DefaultCredentials;  public ICredentials Credentials  {  get  {  return this.m_credentials;  }  set  {  this.m_credentials = value;  }  }  public NameValueCollection QueryString  {  get  {  if (this.m_requestParameters == null)  {  this.m_requestParameters = new NameValueCollection();  }  return this.m_requestParameters;  }  set  {  this.m_requestParameters = value;  }  }  public string BaseAddress  {  get  {  if (this.m_baseAddress != null)  {  return this.m_baseAddress.ToString();  }  return string.Empty;  }  set  {  if ((value == null) || (value.Length == 0))  {  this.m_baseAddress = null;  }  else  {  try  {  this.m_baseAddress = new Uri(value);  }  catch (Exception exception1)  {  throw new ArgumentException("value", exception1);  }  }  }  }  private Uri GetUri(string path)  {  Uri uri1;  try  {  if (this.m_baseAddress != null)  {  uri1 = new Uri(this.m_baseAddress, path);  }  else  {  uri1 = new Uri(path);  }  if (this.m_requestParameters == null)  {  return uri1;  }  StringBuilder builder1 = new StringBuilder();  string text1 = string.Empty;  for (int num1 = 0; num1 < this.m_requestParameters.Count; num1++)  {  builder1.Append(text1 + this.m_requestParameters.AllKeys[num1] + "=" + this.m_requestParameters[num1]);  text1 = "&";  }  UriBuilder builder2 = new UriBuilder(uri1);  builder2.Query = builder1.ToString();  uri1 = builder2.Uri;  }  catch (UriFormatException)  {  uri1 = new Uri(Path.GetFullPath(path));  }  return uri1;  }  }  }  /// <summary>  /// 测试类  /// </summary>  class AppTest  {  int _k = 0;  int _K = 0;  static void Main()  {  AppTest a = new AppTest();  Microshaoft.Utils.HttpWebClient x = new Microshaoft.Utils.HttpWebClient();  a._K = 10;  //订阅 DataReceive　事件  x.DataReceive += new Microshaoft.Utils.HttpWebClient.DataReceiveEventHandler(a.x_DataReceive);  //订阅 ExceptionOccurrs　事件  x.ExceptionOccurrs += new Microshaoft.Utils.HttpWebClient.ExceptionEventHandler(a.x_ExceptionOccurrs);  x.ThreadProcessEnd += new Microshaoft.Utils.HttpWebClient.ThreadProcessEventHandler(a.x_ThreadProcessEnd);  string F = "http://localhost/download/phpMyAdmin-2.6.1-pl2.zip";  F = "http://down6.flashget.com/flashget182cn.exe";  a._F = F;  string f = F.Substring(F.LastIndexOf("/") + 1);  //(new System.Threading.Thread(new System.Threading.ThreadStart(new ThreadProcessState(F, @"E:\temp\" + f, 10, x).StartThreadProcess))).Start();  x.DownloadFile(F, @"d:\temp\" + f, a._K);  // x.DownloadFileChunk(F, @"E:\temp\" + f,15,34556);  System.Console.ReadLine();  // string uploadfile = "e:\\test_local.rar";  // string str = x.UploadFileEx("http://localhost/phpmyadmin/uploadaction.php", "POST", uploadfile, "file1");  // System.Console.WriteLine(str);  // System.Console.ReadLine();  }  string bs = ""; //用于记录上次的位数  bool b = false;  private int i = 0;  private static object _SyncLockObject = new object();  string _F;  string _f;  private void x_DataReceive(Microshaoft.Utils.HttpWebClient Sender, Microshaoft.Utils.DownLoadEventArgs e)  {  if (!this.b)  {  lock (_SyncLockObject)  {  if (!this.b)  {  System.Console.Write(System.DateTime.Now.ToString() + " 已接收数据: ");  //System.Console.Write( System.DateTime.Now.ToString() + " 已接收数据: ");  this.b = true;  }  }  }  string f = e.DownloadState.FileName;  if (e.DownloadState.AttachmentName != null)  f = System.IO.Path.GetDirectoryName(f) + @"\" + e.DownloadState.AttachmentName;  this._f = f;  using (System.IO.FileStream sw = new System.IO.FileStream(f, System.IO.FileMode.OpenOrCreate, System.IO.FileAccess.ReadWrite, System.IO.FileShare.ReadWrite))  {  sw.Position = e.DownloadState.Position;  sw.Write(e.DownloadState.Data, 0, e.DownloadState.Data.Length);  sw.Close();  }  string s = System.DateTime.Now.ToString();  lock (_SyncLockObject)  {  this.i += e.DownloadState.Data.Length;  System.Console.Write(bs + "\b\b\b\b\b\b\b\b\b\b"+ i + " / " + Sender.FileLength + " 字节数据 " + s);  //System.Console.Write(bs + i + " 字节数据 " + s);  this.bs = new string('\b', Digits(i) + 3 + Digits(Sender.FileLength) + s.Length);  }  }  int Digits(int n) //数字所占位数  {  n = System.Math.Abs(n);  n = n / 10;  int i = 1;  while (n > 0)  {  n = n / 10;  i++;  }  return i;  }  private void x_ExceptionOccurrs(Microshaoft.Utils.HttpWebClient Sender, Microshaoft.Utils.ExceptionEventArgs e)  {  System.Console.WriteLine(e.Exception.Message);  //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  Microshaoft.Utils.HttpWebClient x = new Microshaoft.Utils.HttpWebClient();  x.DownloadFileChunk(this._F, this._f, e.DownloadState.Position, e.DownloadState.Length);  e.ExceptionAction = Microshaoft.Utils.ExceptionActions.Ignore;  }  private void x_ThreadProcessEnd(Microshaoft.Utils.HttpWebClient Sender, Microshaoft.Utils.ThreadProcessEventArgs e)  {  //if (e.thread.ThreadState == System.Threading.ThreadState.Stopped)  if (this._k ++ == this._K - 1)  System.Console.WriteLine("\nend");  }  }  。

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