Imports System.IO

Public Class myTestObj
    Implements System.IDisposable

    Private m_TestStr As String

    Public Property TestStr() As String
        Get
            Return m_TestStr
        End Get
        Set(ByVal value As String)
            m_TestStr = value
        End Set
    End Property

    Public Sub New()

    End Sub
    Public Sub New(ByVal myFileName As String)
        m_TestStr = My.Computer.FileSystem.ReadAllText(myFileName)
    End Sub

    Private disposedValue As Boolean = False        ' 偵測多餘的呼叫

    ' IDisposable
    Protected Overridable Sub Dispose(ByVal disposing As Boolean)
        If Not Me.disposedValue Then
            If disposing Then
                ' TODO: 釋放其他狀態 (Managed 物件)。
                m_TestStr = ""
            End If

            ' TODO: 釋放您自己的狀態 (Unmanaged 物件)
            ' TODO: 將大型欄位設定為 null。
        End If
        Me.disposedValue = True
    End Sub

#Region " IDisposable Support "
    ' 由 Visual Basic 新增此程式碼以正確實作可處置的模式。
    Public Sub Dispose() Implements IDisposable.Dispose
        ' 請勿變更此程式碼。在以上的 Dispose 置入清除程式碼 (ByVal 視為布林值處置)。
        Dispose(True)
        GC.SuppressFinalize(Me)
    End Sub
#End Region

End Class

Module Module1
    Sub Main()
        Dim oTest As myTestObj
        Try
            oTest = New myTestObj("xx.txt")
        Catch ex As Exception

        Finally
            oTest.Dispose()
            GC.Collect()
        End Try
    End Sub
End Module