如何在 VB.NET/Visual Studio 2008 中允许空格键和退格键？
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How to allow the space key and backspace key in VB.NET/ Visual Studio 2008?
提问by Prakash Banjara
How do I allow the space key and backspace key in VB.NET/ Visual Studio 2008?
如何在 VB.NET/Visual Studio 2008 中允许空格键和退格键？
Sample code:
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
回答by Mark Hall
For Backspace use the AscFunction and test for the Hex Value, in this case 8, for the Space you can just test for " "
对于 Backspace 使用AscFunction 并测试Hex Value，在本例中为 8，对于 Space，您可以只测试" "
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
If your question is how to check BackSpace and Space the above answer will work. To allow them along with your Text then do something like this
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
回答by Liong
Work at Visual Studio 2012:
在 Visual Studio 2012 工作：
Private Sub Username_KeyPress(sender As Object, e As KeyPressEventArgs) Handles Username.KeyPress
If Not (Char.IsNumber(e.KeyChar) Or Asc(e.KeyChar) = 8 Or Asc(e.KeyChar) = 32) Then
e.Handled = True
End If
End Sub
