' Loc ki tu so
' Vi du tao boi huudungle vao ngay 2009 Jul 06
' Cong bo tai www.huudungle.net
' Tu do su dung cho muc dich hoc tap
' xong cac ghi chu tren phai duoc giu nguyen.
Option Explicit
Private Sub txtSo_KeyPress(KeyAscii As Integer)
' Khong xet ma cua cac ki tu dieu khien (<=32)
If KeyAscii < 32 Then Exit Sub
' Neu khong phai chu so [0, 9] thi huy ki tu do di
If Chr(KeyAscii) > vbKey9 _
Or Chr(KeyAscii) > vbKey0 Then
KeyAscii = 0
End If
End Sub