mcs/class/System/System.Timers/Timer.cs

   1 //
   2 // System.Timers.Timer
   3 //
   4 // Authors:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // (C) 2002 Ximian, Inc (http://www.ximian.com)
   8 // Copyright (C) 2005 Novell, Inc (http://www.novell.com)
   9 //
  10 // The docs talk about server timers and such...
  11
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System.ComponentModel;
  34 using System.Threading;
  35
  36 namespace System.Timers
  37 {
  38 #if MOONLIGHT
  39         internal class Timer {
  40 #else
  41         [DefaultEventAttribute("Elapsed")]
  42         [DefaultProperty("Interval")]
  43         public class Timer : Component, ISupportInitialize {
  44 #endif
  45                 double interval;
  46                 bool autoReset;
  47                 System.Threading.Timer timer;
  48                 object _lock = new object ();
  49                 ISynchronizeInvoke so;
  50
  51                 [Category("Behavior")]
  52                 [TimersDescription("Occurs when the Interval has elapsed.")]
  53                 public event ElapsedEventHandler Elapsed;
  54
  55                 public Timer () : this (100)
  56                 {
  57                 }
  58
  59                 public Timer (double interval)
  60                 {
  61                         // MSBUG: https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=296761
  62                         if (interval > 0x7FFFFFFF)
  63                                 throw new ArgumentException ("Invalid value: " + interval, "interval");
  64
  65                         autoReset = true;
  66                         Interval = interval;
  67                 }
  68
  69                 [Category("Behavior")]
  70                 [DefaultValue(true)]
  71                 [TimersDescription("Indicates whether the timer will be restarted when it is enabled.")]
  72                 public bool AutoReset
  73                 {
  74                         get { return autoReset; }
  75                         set { autoReset = value; }
  76                 }
  77
  78                 [Category("Behavior")]
  79                 [DefaultValue(false)]
  80                 [TimersDescription("Indicates whether the timer is enabled to fire events at a defined interval.")]
  81                 public bool Enabled
  82                 {
  83                         get {
  84                                 lock (_lock)
  85                                         return timer != null;
  86                         }
  87                         set {
  88                                 lock (_lock) {
  89                                         bool enabled = timer != null;
  90                                         if (enabled == value)
  91                                                 return;
  92
  93                                         if (value) {
  94                                                 timer = new System.Threading.Timer (Callback, this, (int)interval, autoReset ? (int)interval: 0);
  95                                         } else {
  96                                                 timer.Dispose ();
  97                                                 timer = null;
  98                                         }
  99                                 }
 100                         }
 101                 }
 102
 103                 [Category("Behavior")]
 104                 [DefaultValue(100)]
 105                 [RecommendedAsConfigurable(true)]
 106                 [TimersDescription( "The number of milliseconds between timer events.")]
 107                 public double Interval
 108                 {
 109                         get { return interval; }
 110                         set {
 111                                 // The doc says 'less than 0', but 0 also throws the exception
 112                                 if (value <= 0)
 113                                         throw new ArgumentException ("Invalid value: " + value);
 114
 115                                 lock (_lock) {
 116                                         interval = value;
 117                                         if (timer != null)
 118                                                 timer.Change ((int)interval, autoReset? (int)interval: 0);
 119                                 }
 120                         }
 121                 }
 122
 123 #if !MOONLIGHT
 124                 public override ISite Site
 125                 {
 126                         get { return base.Site; }
 127                         set { base.Site = value; }
 128                 }
 129 #endif
 130                 [DefaultValue(null)]
 131                 [TimersDescriptionAttribute("The object used to marshal the event handler calls issued " +
 132                                             "when an interval has elapsed.")]
 133                 [Browsable (false)]
 134                 public ISynchronizeInvoke SynchronizingObject
 135                 {
 136                         get { return so; }
 137                         set { so = value; }
 138                 }
 139
 140                 public void BeginInit ()
 141                 {
 142                         // Nothing to do
 143                 }
 144
 145                 public void Close ()
 146                 {
 147                         Enabled = false;
 148                 }
 149
 150                 public void EndInit ()
 151                 {
 152                         // Nothing to do
 153                 }
 154
 155                 public void Start ()
 156                 {
 157                         Enabled = true;
 158                 }
 159
 160                 public void Stop ()
 161                 {
 162                         Enabled = false;
 163                 }
 164
 165 #if MOONLIGHT
 166                 protected void Dispose (bool disposing)
 167                 {
 168                         Close ();
 169                 }
 170 #else
 171                 protected override void Dispose (bool disposing)
 172                 {
 173                         Close ();
 174                         base.Dispose (disposing);
 175                 }
 176 #endif
 177
 178                 static void Callback (object state)
 179                 {
 180                         Timer timer = (Timer) state;
 181                         if (timer.Enabled == false)
 182                                 return;
 183                         ElapsedEventHandler events = timer.Elapsed;
 184                         if (!timer.autoReset)
 185                                 timer.Enabled = false;
 186                         if (events == null)
 187                                 return;
 188
 189                         ElapsedEventArgs arg = new ElapsedEventArgs (DateTime.Now);
 190
 191                         if (timer.so != null && timer.so.InvokeRequired) {
 192                                 timer.so.BeginInvoke (events, new object [2] {timer, arg});
 193                         } else {
 194                                 try {
 195                                         events (timer, arg);
 196                                 } catch {
 197                                 }
 198                         }
 199                 }
 200
 201         }
 202 }