<SerializableAttribute()>
Public Class WeakReference(Of T As Class) 
   Inherits System.WeakReference

[SerializableAttribute()]
public class WeakReference<T> : System.WeakReference 
where T: class

string value1 = "Testing Value - 1";
object value2 = new MyObject();
Utils.WeakReference<string> r = new Utils.WeakReference<string>(value1);

string tmp;
Assert.IsTrue(r.TryGetTarget(out tmp) && tmp == value1);

((WeakReference)r).Target = value2; //incorrect type...
Assert.IsFalse(r.IsAlive);
Assert.IsNull(r.Target);
Assert.IsFalse(r.TryGetTarget(out tmp));

Assert.IsTrue(ReferenceEquals(value2, ((WeakReference)r).Target));

Dim value1 As String = "Testing Value - 1"
Dim value2 As Object = New MyObject()
Dim r As New Utils.WeakReference(Of String)(value1)

Dim tmp As String
Assert.IsTrue(r.TryGetTarget(tmp) AndAlso tmp = value1)

(DirectCast(r, WeakReference)).Target = value2
'incorrect type...
Assert.IsFalse(r.IsAlive)
Assert.IsNull(r.Target)
Assert.IsFalse(r.TryGetTarget(tmp))

Assert.IsTrue(ReferenceEquals(value2, (DirectCast(r, WeakReference)).Target))