VB判断按下了某一键

Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)

MsgBox (Chr(KeyCode) + "被按了一下")

End Sub

在Form_KeyPress事件里写代码判断一下就可以了
比如,
Private Sub Form_KeyPress(KeyAscii As Integer)
If KeyAscii=vbKeyR Then
MsgBox "R被按了一下！"
End If
End Sub

r一下

楼主要的不仅仅是在窗体上按R吧，如果是，则
在窗体_KeyPress事件里写代码判断一下就可以了
比如,
Private Sub 窗体_KeyPress(KeyAscii As Integer)
If KeyAscii=vbKeyR Then
MsgBox "R被按了一下！"
End If
End Sub
如果不是，如下

'模块部分
Public Type EVENTMSG'返回结构
vKey As Long
sKey As Long
flag As Long
time As Long
End Type
'一些声明
Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Long) As Long
Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Long, ByVal lpfn As Long, ByVal hmod As Long, By