mcs/class/Microsoft.Web.Services/Microsoft.Web.Services/AsyncResult.cs

   1 //
   2 // Microsoft.Web.Services.AsyncResult.cs
   3 //
   4 // Author: Todd Berman <tberman@gentoo.org>
   5 //
   6 // (C) 2003 Todd Berman
   7
   8 using System;
   9 using System.Threading;
  10
  11 namespace Microsoft.Web.Services
  12 {
  13         public class AsyncResult : IAsyncResult
  14         {
  15                 private AsyncCallback _callback;
  16                 private bool _completed;
  17                 private bool _completedSync;
  18                 private bool _endCalled;
  19                 private ManualResetEvent _event;
  20                 private Exception _exception;
  21                 private object _state;
  22
  23                 protected AsyncResult (object s) : this (null, s)
  24                 {
  25                 }
  26
  27                 protected AsyncResult (AsyncCallback call, object s) : base ()
  28                 {
  29                         _callback = call;
  30                         _state = s;
  31                 }
  32
  33                 protected AsyncResult () : this (null, null)
  34                 {
  35                 }
  36
  37                 protected void Complete (bool csync, Exception e)
  38                 {
  39                         _completed = true;
  40                         _completedSync = csync;
  41                         _exception = e;
  42
  43                         if(_event != null) {
  44                                 _event.Set ();
  45                         }
  46                         try {
  47                                 if(_callback != null) {
  48                                         _callback (this);
  49                                 }
  50                         } catch (Exception) {
  51                                 ThreadPool.QueueUserWorkItem (new WaitCallback (ThrowException), this);
  52                         }
  53                 }
  54
  55                 protected void Complete (bool csync)
  56                 {
  57                         this.Complete (csync, null);
  58                 }
  59
  60                 public static void End (IAsyncResult result)
  61                 {
  62                         if(result == null) {
  63                                 throw new ArgumentNullException ("result");
  64                         }
  65                         AsyncResult mws_result = (AsyncResult) result;
  66
  67                         if(mws_result == null) {
  68                                 throw new ArgumentException ("Invalid result");
  69                         }
  70
  71                         if(mws_result._endCalled == true) {
  72                                 throw new InvalidOperationException ("Async Operation already finished");
  73                         }
  74
  75                         mws_result._endCalled = true;
  76
  77                         if(mws_result._completed == true) {
  78                                 mws_result.AsyncWaitHandle.WaitOne ();
  79                         }
  80
  81                         if(mws_result._exception != null) {
  82                                 throw mws_result._exception;
  83                         }
  84                 }
  85
  86                 private void ThrowException (object o)
  87                 {
  88                         Exception e = (Exception) o;
  89                         throw e;
  90                 }
  91
  92                 public object AsyncState {
  93                         get { return _state; }
  94                 }
  95
  96                 public WaitHandle AsyncWaitHandle {
  97                         get {
  98                                 if(_event == null) {
  99                                         bool complete = _completed;
 100
 101                                         lock (this) {
 102                                                 _event = new ManualResetEvent (_completed);
 103                                         }
 104                                         if(complete == true || _completed == false) {
 105                                                 _event.Set ();
 106                                         }
 107                                 }
 108                                 return _event;
 109                         }
 110                 }
 111
 112                 public bool CompletedSynchronously {
 113                         get { return _completedSync; }
 114                 }
 115
 116                 public bool IsCompleted {
 117                         get { return _completed; }
 118                 }
 119         }
 120 }