Visual Basic密鑰監聽器

Question

我正試圖在Visual Basic（VS 2010）中編寫一個程序來響應箭頭鍵。我知道在Java中有關鍵的監聽器，但不知道在VB中是否存在這樣的事情以及如何對它進行編碼。請給我看一些例子。 謝謝。

Answer 1

如果您正在執行winforms，請將表單的KeyPreview屬性設置爲true，然後設置KeyDown事件。您的代碼將如下所示：

Dim previousKey As Keys? = Nothing 

Private Sub Form1_KeyDown(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles MyBase.KeyDown 
    If e.KeyCode = Keys.Up Then 
     'up arrow 
    End If 


    If e.KeyCode = Keys.Left Then 
     'left arrow 
     If Not previousKey Is Nothing And previousKey = Keys.Up Then 
      'Up arrow and then Left Arrow 
      MessageBox.Show("there, that's better") 
     End If 
    End If 

    If e.KeyCode = Keys.Right Then 
     'right arrow 
    End If 

    If e.KeyCode = Keys.Down Then 
     'down arrow 
    End If 

    'After everything is done set the current key as the previous key. 
    previousKey = e.KeyCode 
End Sub