最近因为想写一个多线程的工具,以前也没写过;所以查了些VB多线程资料;方法虽然有很多,但我觉得这种是最简单而且又安全的一种真真的VB多线程方法。
大家往下看吧,分2大步骤;
1、新建一个工程,类型选择ActiveX Exe,工程重命名为TestExe 在工程中添加一个Form,放上一个Timer控件。 注:Timer 控件 interval值别忘了设置。 将Class1改名为clsTest,注意其Instancing要设置为5-MultiUse。
以下是clsTest类模块其代码:
Option Explicit Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long) Private WithEvents oTimer As Timer Private frmTmp As Form1 Private lTotalLoop As Long Private bDoStop As Boolean Private lInterval As Long
Public Event Progress(ByVal lProgress As Long)
Public Sub StartSub(ByVal lTotal As Long) lTotalLoop = lTotal oTimer.Enabled = True End Sub
Public Sub StopSub() bDoStop = True End Sub
Private Sub Class_Initialize() Set frmTmp = New Form1 Load frmTmp Set oTimer = frmTmp.Timer1 oTimer.Enabled = False bDoStop = False lInterval = 1 End Sub
Private Sub DoLoop() Dim i As Long For i = 0 To lTotalLoop Sleep (lInterval) RaiseEvent Progress(i) If bDoStop = True Then Exit Sub End If Next End Sub
Private Sub Class_Terminate() Unload frmTmp Set frmTmp = Nothing Set oTimer = Nothing End Sub
Private Sub oTimer_Timer() oTimer.Enabled = False DoLoop End Sub
Public Property Get lMillisecs() As Long lMillisecs = lInterval End Property
Public Property Let lMillisecs(ByVal vNewValue As Long) lInterval = vNewValue End Property
在TestExe 工程属性的通用页下,选择线程缓冲沲,线程数值设值为2。 则调用此ActiveX Exe最多能同时有两个线程, 更多的请求将放置于队列中。
编译生成TestExe
2、下面来测试我们的多线程程序:
新建一个标准 Exe工程,在“引用”中选择刚刚编译生成的TestExe.exe 在Form1中添加两个ListBox,两个CommandButton,Command1为开始,Command2为停止
以下是Project1.Form1的代码:
Option Explicit Private WithEvents oTest1 As TestEXE.clsTest Private WithEvents oTest2 As TestEXE.clsTest
Private Sub Command1_Click() Set oTest1 = New TestEXE.clsTest oTest1.lMillisecs = 100 oTest1.StartSub (1000) Set oTest2 = New TestEXE.clsTest oTest2.lMillisecs = 100 oTest2.StartSub (1000) End Sub
Private Sub Command2_Click() oTest1.StopSub oTest2.StopSub End Sub
Private Sub Form_Unload(Cancel As Integer) Set oTest1 = Nothing Set oTest2 = Nothing End Sub
Private Sub oTest1_Progress(ByVal lProgress As Long) List1.AddItem lProgress List1.ListIndex = List1.ListCount - 1 End Sub
Private Sub oTest2_Progress(ByVal lProgress As Long) List2.AddItem lProgress List2.ListIndex = List2.ListCount - 1 End Sub
大功告成,启动运行form1,点击Command1,怎么样,看见来效果了吗?
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