Question

有关VB中TextBox控件的问题

要求：控制TextBox控件，使得输入的字符只能为数字。
满足该要求的代码应该怎么写？

Answer 1

更简单的办法，先声明一个常数，包含你限制输入的字符，在用户键入时做判断用户输入的是否在其中

Const xStr As String = "0123456789" '如果想限制其他的字符就都写进这里，如新身份证号中会有字母x，把x加进来，用户就只能输入数字和x了

Private Sub Text1_KeyPress(KeyAscii As Integer)
KeyAscii = IIf(InStr(xStr & Chr(8), Chr(KeyAscii)), KeyAscii, 0)
End Sub

Answer 2

改进2楼的代码:
Private Sub Text2_KeyPress(KeyAscii As Integer)
Const xStr As String = "0123456789.-"
If KeyAscii = 46 And InStr(Text2, ".") > 0 Then KeyAscii = 0 '只能输入一个小数点
If KeyAscii = 45 And Len(Text2) > 0 Then KeyAscii = 0 '只能在最前面输入-号
If KeyAscii = 8 Then Exit Sub '退格键不受限制
KeyAscii = IIf(InStr(xStr, Chr(KeyAscii)), KeyAscii, 0) '只能输入规定的字符

End Sub

Answer 3

Private Sub textbox1_KeyPress(KeyAscii As Integer)
If KeyAscii <> vbKeyBack And KeyAscii < 48 Or KeyAscii > 57 And KeyAscii <> 13 Then
KeyAscii = 0
End If
End Sub

利用 keyascii 来实现就好，建议还是自己具体操作一下就知道。

Answer 4

Private Sub Text1_Change(Index As Integer)
if text1.text<>"" then
if ltrim(str(val(text1.text)))<>text1.text then text1.text=""
end if
End Sub