Question

我知道这已经多次讨论了，但似乎没有解决方案可行，所以我想，并且可能值得尝试重新打开它，因为一段时间过去了。

我有一个功能：

Public Function Test() As Object
    Dim retVal As DisposableObject
    Dim tempRetVal As DisposableObject
    Try
        tempRetVal = New DisposableObject
        retVal = tempRetVal
        tempRetVal = Nothing
        Return retVal
    Catch
        tempRetVal.Dispose()
        Throw
    Finally
        tempRetVal.Dispose()
    End Try
End Function

如您所见，有很多Dispose语句。这是因为我试图找到一种让它工作的方法。我找到的唯一方法（显然不是解决方案）是在返回retval之前添加retVal.Dispose()。

 Public Function Test() As Object
    Dim retVal As DisposableObject
    Dim tempRetVal As DisposableObject
    Try
        tempRetVal = New DisposableObject
        retVal = tempRetVal
        tempRetVal = Nothing
        retVal.Dispose()
        Return retVal
    Catch
        tempRetVal.Dispose()
        Throw
    Finally
        tempRetVal.Dispose()
    End Try
End Function

任何提示都将很高兴！：）

注意：我正在使用VS2012

修改我也尝试过MS提出的简单模板，它也不起作用：

Public Function Test() As Object
    Dim retVal As DisposableObject
    Dim tempRetVal As DisposableObject
    Try
        tempRetVal = New DisposableObject
        retVal = tempRetVal
        tempRetVal = Nothing
        Return retVal
    Finally
        if tempRetVal isnot Nothing then tempRetVal.Dispose()
    End Try
End Function

tempRetVal = New DisposableObject上会引发CA2000。

Answer 1

我找到的唯一方法（显然不是解决方案）是添加在返回retval之前retVal.Dispose（）。

为什么呢？你总是定义了finally块。让最后的块来处理。您的代码应如下所示。另外，

 Public Function Test() As Object
    Dim retVal As LLServerConnection
    Dim tempRetVal As LLServerConnection
    Try
        tempRetVal = New LLServerConnection
        retVal = tempRetVal
        tempRetVal = Nothing
        Return retVal
    Catch
        Throw
    Finally
        If Not tempRetVal Is Nothing Then
        tempRetVal.Dispose()
    End Try
End Function

有关详细信息，请参阅CA2000: Dispose objects before losing scope。

修改

我相信，由于return块内的TRY语句，您收到了CA2000警告消息。相反，return在子程序实际结束之前的对象。请参阅以下代码，并在更改中添加注释。现在好了。

Public Function Test() As DisposableObject //Change object to actual type DisposableObject Dim retVal As DisposableObject = Nothing Dim tempRetVal As DisposableObject = Nothing Try tempRetVal = New DisposableObject() retVal = tempRetVal tempRetVal = Nothing Finally If Not tempRetVal Is Nothing Then tempRetVal.Dispose() End If End Try Return retVal //Return the object before your subroutine ends End Function

CA2000警告返回值

1 个答案: