mcs/class/System.Windows.Forms/System.Windows.Forms/Timer.cs

   1 //
   2 // System.Windows.Forms.Timer
   3 //
   4 // Author:
   5 //      stubbed out by Jackson Harper (jackson@latitudegeo.com)
   6 //      Dennis Hayes (dennish@raytek.com)
   7 //      Aleksey Ryabchuk (ryabchuk@yahoo.com)
   8 //
   9 // (C) 2002/3 Ximian, Inc
  10 //
  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.Runtime.InteropServices;
  35 using System.Collections;
  36
  37 namespace System.Windows.Forms {
  38
  39         // <summary>
  40         //      Represents a timer that raises an event at user-defined intervals.
  41         // </summary>
  42         public class Timer : Component {
  43
  44                 private bool enabled = false;
  45                 private int  interval = 100;
  46                 private uint timerid = 0;
  47                 private GCHandle timerHandle;
  48                 private Win32.TimerProc proc;
  49
  50                 public Timer(){
  51                 }
  52
  53                 public Timer( IContainer container ) {
  54                         container.Add ( this );
  55                 }
  56
  57                 public virtual bool Enabled {
  58                         get {
  59                                 return enabled;
  60                         }
  61                         set {
  62                                 enabled = value;
  63                                 if ( enabled ) {
  64                                         if ( timerid != 0 )
  65                                                 Win32.KillTimer ( IntPtr.Zero , timerid );
  66
  67                                         if ( !timerHandle.IsAllocated )
  68                                                 timerHandle = GCHandle.Alloc( this );
  69
  70                                         if ( proc == null )
  71                                                 proc = new Win32.TimerProc( this.TimeProc );
  72
  73                                         timerid = Win32.SetTimer( IntPtr.Zero,  0, (uint)Interval, proc );
  74                                 }
  75                                 else {
  76                                         if ( timerid != 0 )
  77                                                 Win32.KillTimer ( IntPtr.Zero , timerid );
  78
  79                                         timerid = 0;
  80
  81                                         if ( timerHandle.IsAllocated )
  82                                                 timerHandle.Free();
  83                                 }
  84                         }
  85                 }
  86
  87                 public int Interval {
  88                         get {
  89                                 return interval;
  90                         }
  91                         set {
  92                                 if ( value <= 0 )
  93                                         throw new ArgumentException (
  94                                         string.Format (" '{0}' is not a valid value for Interval. Interval must be greater than 0.",
  95                                                         value ) );
  96                                 interval = value;
  97                                 if ( Enabled )
  98                                         Enabled = true; // restart
  99                         }
 100                 }
 101
 102                 public void Start() {
 103                         Enabled = true;
 104                 }
 105
 106                 public void Stop() {
 107                         Enabled = false;
 108                 }
 109
 110                 public override string ToString()
 111                 {
 112                         return "[" + GetType().FullName.ToString() + "], Interval: " + Interval;
 113                 }
 114
 115                 public event EventHandler Tick;
 116
 117                 protected virtual void OnTick(EventArgs e)
 118                 {
 119                         if ( Tick != null )
 120                                 Tick ( this, e );
 121                 }
 122
 123                 private void TimeProc( IntPtr hwnd, uint uMsg, uint idEvent, int dwTime )
 124                 {
 125                         OnTick ( EventArgs.Empty );
 126                 }
 127
 128                 protected override void Dispose( bool disposing ) {
 129                         Enabled = false;
 130                         base.Dispose ( disposing );
 131                 }
 132         }
 133 }