如何在VB.NET/Visual Studio 2008中允许空格键和退格键？

Question

如何在VB.NET/Visual Studio 2008中允许空格键和退格键？

示例代码:

Private Sub txtname_KeyPress(ByVal sender As System.Object, _
                             ByVal e As System.Windows.Forms.KeyPressEventArgs) _
                             Handles txtname.KeyPress

    If e.KeyChar < "A" Or e.KeyChar > "z" And e.KeyChar <> ControlChars.Back Then
        e.Handled = True
        txtname.Clear()
    Else
    End If
End Sub

Answer 1

对于退格键,使用Asc函数和测试十六进制值,在本例中为8,对于您可以测试的空间" "

If Asc(e.KeyChar) = 8 OrElse e.KeyChar = " " OrElse e.KeyChar < "A" OrElse e.KeyChar > "z" Then
    e.Handled = True
    CType(sender, TextBox).Clear()
End If

如果您的问题是如何检查BackSpace和Space,则上述答案将起作用.要允许它们与您的文本一起使用,请执行以下操作

If Not ((Asc(e.KeyChar) = 8 OrElse e.KeyChar = " ") OrElse (e.KeyChar >= "A" AndAlso e.KeyChar <= "z")) Then
    e.Handled = True
    CType(sender, TextBox).Clear()
End If