VB怎样判断、防止程序重复执行
Private Sub Form_load()
'判断程序是否已经运行
If App.PrevInstance
Then
MsgBox "本程序已经运行！", vbInformation Or vbOKOnly, "提示信息"
Unload
Me
Exit Sub
End If
'以下是主要程序
' ……
End
Sub
附：另一个例子：
Option Explicit
Public Sub CheckExist(fm
As Form) '防止程序重复执行
Dim title As String
If App.PrevInstance
Then
title = App.title
Call MsgBox("这程序已执行",
vbCritical)
App.title = "" '如此才不会 Avtivate 到自己
fm.Caption =
""
AppActivate title 'activate 先前就已运行的程序
End ' 结束
End
If
End Sub
Private Sub Form_Load()
Call
CheckExist(Me)
End Sub
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