blob: 12541ac7c6f328f5d7616498f6184fdd406696d0 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
//
// System.WeakReference.cs
//
// Author:
// Ajay kumar Dwivedi (adwiv@yahoo.com)
//
using System.Runtime.Serialization;
using System.Runtime.InteropServices;
namespace System
{
/// <summary>
/// Summary description for WeakReference.
/// </summary>
[Serializable]
public class WeakReference : ISerializable
{
//Fields
private bool isLongReference;
private GCHandle gcHandle;
// Helper method for constructors
//Should not be called from any other method.
private void AllocateHandle(Object target)
{
if(this.isLongReference)
{
this.gcHandle = GCHandle.Alloc(target, GCHandleType.WeakTrackResurrection);
}
else
{
this.gcHandle = GCHandle.Alloc(target, GCHandleType.Weak);
}
}
//Constructors
public WeakReference(object target)
: this(target,false)
{}
public WeakReference(object target, bool trackResurrection)
{
this.isLongReference = trackResurrection;
AllocateHandle(target);
}
protected WeakReference(SerializationInfo info, StreamingContext context)
{
if (info == null)
throw new ArgumentNullException ("info");
this.isLongReference = info.GetBoolean("IsLongReference");
//TODO: How to load the exact type?
//Does that matter? No idea :(
Object target = info.GetValue("TargetObject",typeof(System.Object));
AllocateHandle(target);
}
// Properties
public virtual bool IsAlive
{
get
{
//Target property takes care of the exception
return (Target != null);
}
}
public virtual object Target
{
get
{
//Exception is thrown by gcHandle's Target
return this.gcHandle.Target;
}
set
{
this.gcHandle.Target = value;
}
}
public virtual bool TrackResurrection
{
get
{
return this.isLongReference;
}
}
//Methods
~WeakReference()
{
gcHandle.Free();
}
//TODO
public virtual void GetObjectData(SerializationInfo info,StreamingContext context)
{
if (info == null)
throw new ArgumentNullException ("info");
info.AddValue("IsLongReference",this.isLongReference);
try
{
info.AddValue("TargetObject",Target);
}
catch(Exception)
{
info.AddValue("TargetObject",null);
}
}
}
}
|
