source: trunk/ab5.0/ablib/src/Classes/System/Runtime/InteropServices/GCHandle.ab@ 536

' Classes/System/Runtime/InteropServices/GCHandle.ab

Namespace System
Namespace Runtime
Namespace InteropServices

Class GCHandle
Public
    Function Target() As Object
        Target = _System_PtrObj(handle)
    End Function

    Sub Target(obj As Object)
        If handle <> 0 Then
            Dim i = allocated.IndexOf(Target())
            'assert(i <> -1)
            allocated[i] = obj
        End If
        allocated.Add(obj)
        handle = ObjPtr(obj)
    End Sub

    Const Function IsAllocated() As Boolean
        Return handle <> 0
    End Function

    Static Function Alloc(obj As Object) As GCHandle
        Alloc = New GCHandle
        Alloc.Target = obj
    End Function

    Sub Free()
        allocated.Remove(Target)
        handle = 0
    End Sub

    Static Function ToIntPtr(h As GCHandle) As LONG_PTR
        Return h.handle As LONG_PTR
    End Function

    Static Function FromIntPtr(ip As LONG_PTR) As GCHandle
        If ip = 0 Then
            Throw New InvalidOperationException("GCHandle.FromIntPtr: ip is 0.")
        End If
        FromIntPtr = New GCHandle
        FromIntPtr.handle = ip As VoidPtr
    End Function

    Override Function GetHashCode() As Long
        Return _System_HashFromPtr(handle)
    End Function

    Function Equals(y As GCHandle) As Boolean
        Return handle = y.handle
    End Function

    Function Operator == (y As GCHandle) As Boolean
        Return Equals(y)
    End Function

    Function Operator <> (y As GCHandle) As Boolean
        Return Not Equals(y)
    End Function

    Override Function ToString() As String
        Return "System.Runtime.InteropServices.GCHandle"
    End Function

'Private
    Sub GCHandle()
    End Sub

Private
    handle As VoidPtr

    Static allocated = New System.Collections.Generic.List<Object>
End Class

End Namespace 'System
End Namespace 'Runtime
End Namespace 'InteropServices