小弟我想按一个键,把当前的字符删一个,8的acii 是退格。但参数类型不对,如何改

我想按一个键,把当前的字符删一个,8的acii 是退格。但参数类型不对,怎么改?
MyText_KeyPress(MyText,   8)

我想按一个键,把当前的字符删一个,8的acii   是退格。但参数类型不对,怎么改?

------解决方案--------------------
Private Sub MyText_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
Dim str As String = MyText.Text
MyText.Text = str.Substring(0, str.Length - 1)
End Sub