mcs/class/corlib/System/Delegate.cs

   1 //
   2 // System.Delegate.cs
   3 //
   4 // Author:
   5 //   Miguel de Icaza (miguel@ximian.com)
   6 //
   7 // (C) Ximian, Inc.  http://www.ximian.com
   8 //
   9 // TODO:  Mucho left to implement
  10 //
  11
  12 using System;
  13 using System.Runtime.Serialization;
  14
  15 namespace System {
  16
  17         public abstract class Delegate : ICloneable, ISerializable {
  18                 protected Type target_type;
  19                 protected object m_target;
  20                 protected string method;
  21                 protected IntPtr method_ptr;
  22
  23                 protected Delegate (object target, string method)
  24                 {
  25                         if (target == null)
  26                                 throw new ArgumentNullException ("Target object is null");
  27
  28                         if (method == null)
  29                                 throw new ArgumentNullException ("method name is null");
  30
  31                         this.target_type = null;
  32                         this.method_ptr = IntPtr.Zero;
  33                         this.m_target = target;
  34                         this.method = method;
  35                 }
  36
  37                 protected Delegate (Type target_type, string method)
  38                 {
  39                         if (m_target == null)
  40                                 throw new ArgumentNullException ("Target type is null");
  41
  42                         if (method == null)
  43                                 throw new ArgumentNullException ("method string is null");
  44
  45                         this.target_type = target_type;
  46                         this.method_ptr = IntPtr.Zero;
  47                         this.m_target = null;
  48                         this.method = method;
  49                 }
  50
  51 #if NOTYET
  52                 public MethodInfo Method {
  53                         get {
  54                                 return null;
  55                         }
  56                 }
  57 #endif
  58
  59                 public object Target {
  60                         get {
  61                                 return m_target;
  62                         }
  63                 }
  64
  65
  66                 //
  67                 // Methods
  68                 //
  69
  70                 public abstract object Clone ();
  71
  72                 public override bool Equals (object o)
  73                 {
  74                         if (!(o is System.Delegate))
  75                                 return false;
  76
  77                         Delegate d = (Delegate) o;
  78
  79                         if ((d.target_type == target_type) &&
  80                             (d.m_target == m_target) &&
  81                             (d.method == method))
  82                                 return true;
  83
  84                         return false;
  85                 }
  86
  87                 public override int GetHashCode ()
  88                 {
  89                         return method.GetHashCode ();
  90                 }
  91
  92                 // This is from ISerializable
  93                 public void GetObjectData (SerializationInfo info, StreamingContext context)
  94                 {
  95                         // TODO: IMPLEMENT ME
  96                 }
  97
  98                 public static Delegate Combine (Delegate a, Delegate b)
  99                 {
 100                         if (a == null){
 101                                 if (b == null)
 102                                         return null;
 103                                 return b;
 104                         } else
 105                                 if (b == null)
 106                                         return a;
 107
 108                         if (a.GetType () != b.GetType ())
 109                                 throw new ArgumentException ("Incompatible Delegate Types");
 110
 111                         return a.CombineImpl (b);
 112                 }
 113
 114                 protected virtual Delegate CombineImpl (Delegate d)
 115                 {
 116                         throw new MulticastNotSupportedException ("");
 117                 }
 118         }
 119 }