C# > VB 转换，RelayCommand 的行为不同

Question

    [Visual C#]
    public ICommand MyCommand
    {
        get
        {
            if (this.myCommand == null)
            {
                this.myCommand = new RelayCommand(this.ShowMyCommand);
            }

            return this.myCommand;
        }
    }

    private void ShowMyCommand(object param)
    {
        ...
    }

这段代码工作正常，但是当我将它转换为 Visual Basic 时:

[Visual Basic]
Private _myCommand As RelayCommand
Public ReadOnly Property MyCommand As ICommand
    Get
        If Me._myCommand Is Nothing Then
            Me._myCommand = New RelayCommand(Me.ShowMyCommand)
        End If

        Return Me._myCommand
    End Get
End Property

Private Sub ShowMyCommand(ByVal param As Object)

    ...

End Sub

我得到错误:

Error 3 Argument not specified for parameter 'param' of 'Private Sub ShowMyCommand(param As Object)'.

有什么想法吗？我只是在盲目转换所以我不明白这个项目是做什么的，我只是在转换它。

Answer 1

对于 VB，我有点如履薄冰，但据我所知，您需要在方法名称前加上关键字 AddressOf 才能将其用作事件的方法组。

下面一行:

Me._myCommand = New RelayCommand(Me.ShowMyCommand)

需要写成:

Me._myCommand = New RelayCommand(AddressOf Me.ShowMyCommand)

错误消息是因为编译器正在尝试编译对该方法的调用，因此缺少对其参数的参数。