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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如何去优化你的VB程序帮助
1、如何去优化你的VB程序
Visual Basic 作为一种高级编程语言，它也有着不可避免的缺点---开发出的应用程序运行速度慢。如果我们能够程序做一些优化，那么情况将会大大改善。要优化程序运行的实际速度，常用的方法有三种：
1.尽量避免使用 Variant 变量。由于VB不能确定 Variant 变量的� ......
'代码:
Option Explicit
'======================用于查找进程和终止进程的API函数常数定义================ =====
Private Declare Function CreateToolhelpSnapshot Lib "kernel32" Alias "CreateToolhelp32Snapshot" (ByVal lFlags As Long, ByVal lProcessID As Long) As Long
Private Declare Function ProcessF ......
Option Explicit
Private Const INTERNET_OPEN_TYPE_DIRECT = 1
Private Const scuseragent = "vb wininet"
Private Const INTERNET_FLAG_PASSIVE = &H8000000
'调用设置环境
Private Declare Function InternetOpen Lib "wininet.dll" Alias "InternetOpenA" (ByVal sAgent As String, ByVal lAccessType As Long ......
VERSION 5.00
Begin VB.Form Form2
AutoRedraw = -1 'True
Caption = "计算界面"
ClientHeight = 4905
ClientLe ......
建一个模块
Public Declare Function GetOpenFileName Lib "comdlg32.dll" Alias "GetOpenFileNameA" (pOpenfilename As OPENFILENAME) As Long
Public Type OPENFILENAME
lStructSize As Long
hwndOwner As Long
hInstance As Long
lpstrFilter As String
lpstrCustomFilt ......
