无法将“System.EventArgs”类型的对象转换为“System.Windows.Forms.KeyEventArgs”类型

Question

这是我的代码：

我有表单加载功能：

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    AddHandler KeyDown, AddressOf Form1_KeyDown
    RaiseEvent KeyDown(Me, e)
End Sub

我有事件声明：

Event KeyDown(ByVal sender As Object, ByVal e As KeyEventArgs)

以及按下控制键时应该打开MsgBox的功能：

Private Sub Form1_KeyDown(ByVal sender As Object, ByVal e As KeyEventArgs)
    If e.KeyCode = Keys.Control Then
        MsgBox("test")
    End If
End Sub

但我有这个错误：

System.InvalidCastException : 'Impossible d'effectuer un cast d'un object de type 'System.EventArgs' en type 'System.Windows.Forms.KeyEventArgs'。'

这是完整的错误信息

所以我不知道该怎么办

Answer 1

设置Form.KeyPreview = True

另外，您的Keys.Control 是控制修饰符，您可能正在寻找Keys.ControlKey

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Me.KeyPreview = True
    AddHandler Me.KeyDown, AddressOf Form1_KeyDown
End Sub

Private Sub Form1_KeyDown(sender As Object, e As KeyEventArgs)
    If e.KeyCode = Keys.ControlKey Then MsgBox("test")
End Sub