vb实现多线程的问题？？？

2002-09-03 09:49:52 114 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

vb多线程:怎样用VB写多线程尽管vb5是apprent single-thread(单线程)的.但用addressof加上一些api,就可以非常容易的做多线程.(比vc容易的多,做出来的东西也一样快,因为都是用api). 每一个县城(线程,下同)约占用20毫秒的时间片. vb5有一个主线程.我们可以另外加一个工作线程.对于不清楚什么是单/多线程的程序元,我们用一个简单的列子来说明一下. 再form里加上两个timer控件. 阅读详情

如何实现，需要一小段例子代码就可以了
请发到lgonnet@263.net，多谢了

...全文

VB6多线程探秘 VB6稳定多线程，一直是争论很大的的。比较稳定的多线程，一般使用 set MT=CreateObject（"VbMT.MT") 但其他单元线程之间，是无法访问的，只有在创建者中，才可使用该对象MT. 还有一个问题，如果设置单元线程停止，一般通过设置属性，比如MT.bStop=True，设停止参数，然后再单元线程中通过检测bStop而退出的。但问题来了，如果单元线程挂起，通过阅读详情

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切换为时间正序

daviddivad 2002-09-03

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给你一个多线程的类：
VERSION 1.0 CLASS
BEGIN
MultiUse = -1 'True
Persistable = 0 'NotPersistable
DataBindingBehavior = 0 'vbNone
DataSourceBehavior = 0 'vbNone
MTSTransactionMode = 0 'NotAnMTSObject
END
Attribute VB_Name = "clsThreading"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = True
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = True
Option Explicit

'=======================================多线程===================================
'注意：当你用了多线程时，你要结束你的程序时，简单的用END是不行的，而要杀掉当前进程序
'
'Private Declare Function GetCurrentProcess Lib "kernel32" () As Long
'Private Declare Function TerminateProcess Lib "kernel32" (ByVal hProcess As Long, ByVal uExitCode As Long) As Long

'eg: Call TerminateProcess(GetCurrentProcess, ByVal 0&)

'API Declarations
'Creates a new thread
Private Declare Function CreateThread Lib "kernel32" (ByVal lpThreadAttributes As Any, ByVal dwStackSize As Long, ByVal lpStartAddress As Long, lpParameter As Any, ByVal dwCreationFlags As Long, lpThreadID As Long) As Long
'Terminates a thread
Private Declare Function TerminateThread Lib "kernel32" (ByVal hThread As Long, ByVal dwExitCode As Long) As Long
'Sets the priority of a thread
Private Declare Function SetThreadPriority Lib "kernel32" (ByVal hThread As Long, ByVal nPriority As Long) As Long
'Returns the proirity of a thread
Private Declare Function GetThreadPriority Lib "kernel32" (ByVal hThread As Long) As Long
'Enables a disabled Thread
Private Declare Function ResumeThread Lib "kernel32" (ByVal hThread As Long) As Long
'Disables a thread
Private Declare Function SuspendThread Lib "kernel32" (ByVal hThread As Long) As Long
'Returns the handle of the current thread
Private Declare Function GetCurrentThread Lib "kernel32" () As Long
'Returns the ID of the current thread
Private Declare Function GetCurrentThreadId Lib "kernel32" () As Long

'Consts
Private Const MAXLONG = &H7FFFFFFF

'Thread priority consts
Private Const THREAD_BASE_PRIORITY_IDLE = -15
Private Const THREAD_BASE_PRIORITY_LOWRT = 15
Private Const THREAD_BASE_PRIORITY_MAX = 2
Private Const THREAD_BASE_PRIORITY_MIN = -2
Private Const THREAD_PRIORITY_HIGHEST = THREAD_BASE_PRIORITY_MAX
Private Const THREAD_PRIORITY_LOWEST = THREAD_BASE_PRIORITY_MIN
Private Const THREAD_PRIORITY_ABOVE_NORMAL = (THREAD_PRIORITY_HIGHEST - 1)
Private Const THREAD_PRIORITY_BELOW_NORMAL = (THREAD_PRIORITY_LOWEST + 1)
Private Const THREAD_PRIORITY_ERROR_RETURN = (MAXLONG)
Private Const THREAD_PRIORITY_IDLE = THREAD_BASE_PRIORITY_IDLE
Private Const THREAD_PRIORITY_NORMAL = 0
Private Const THREAD_PRIORITY_TIME_CRITICAL = THREAD_BASE_PRIORITY_LOWRT

'Thread creation flags
Private Const CREATE_ALWAYS = 2
Private Const CREATE_NEW = 1
Private Const CREATE_NEW_CONSOLE = &H10
Private Const CREATE_NEW_PROCESS_GROUP = &H200
Private Const CREATE_NO_WINDOW = &H8000000
Private Const CREATE_PROCESS_DEBUG_EVENT = 3
Private Const CREATE_SUSPENDED = &H4
Private Const CREATE_THREAD_DEBUG_EVENT = 2

'Types and Enums
Public Enum ThreadPriority
tpLowest = THREAD_PRIORITY_LOWEST
tpBelowNormal = THREAD_PRIORITY_BELOW_NORMAL
tpNormal = THREAD_PRIORITY_NORMAL
tpAboveNormal = THREAD_PRIORITY_ABOVE_NORMAL
tpHighest = THREAD_PRIORITY_HIGHEST
End Enum

'Vars
Private mThreadHandle As Long
Private mThreadID As Long
Private mPriority As Long
Private mEnabled As Boolean
Private mCreated As Boolean

Public Function CreateNewThread(ByVal cFunction As Long, Optional ByVal cPriority As ThreadPriority = tpNormal, Optional ByVal cEnabled As Boolean = True)
'Creates a new Thread
Dim mHandle As Long
Dim CreationFlags As Long
Dim lpThreadID As Long

'Look if the thread has already been created
If mCreated = True Then Exit Function

'Look if the thread should be enabled
If cEnabled = True Then
CreationFlags = 0
Else
'Create a disabled thread, can be enabled later with the
''Enabled' property
CreationFlags = CREATE_SUSPENDED
End If

'The CreateThread Function returns the handle of the created thread;
'if the handle is 0, it failed creating the thread
mHandle = CreateThread(ByVal 0&, ByVal 0&, cFunction, ByVal 0&, CreationFlags, lpThreadID)

If mHandle = 0 Then 'Failed creating the thread
'Insert your own error handling
'Debug.Print "InitializeThread Function in clsThreading failed creating a new thread"
Else
mThreadHandle = mHandle
mThreadID = lpThreadID
mCreated = True
End If
End Function

Public Function TerminateCurrentThread()
'Terminates the current thread

'Ignore errors to prevent crashing if no thread has been created
On Error Resume Next
'Terminate the thread to prevent crashing if the app is closed
'and the thread is still running (dangerous!)
Call TerminateThread(mThreadHandle, ByVal 0&)
mCreated = False
End Function

Public Property Get ThreadHandle() As Long
'Returns the Handle of the current Thread
ThreadHandle = mThreadHandle
End Property

Public Property Get ThreadID() As Long
'Returns the ID of the current thread
ThreadID = mThreadID
End Property

Public Property Get Priority() As Long
'Returns a long value because the thread might have other priorities
'than our five in the enum

'Ignore errors to prevent crashing if no thread has been created
On Error Resume Next
Priority = GetThreadPriority(mThreadHandle)
End Property

Public Property Let Priority(ByVal tmpValue As ThreadPriority)
'Sets the Thread Priority of the actual thread
mPriority = tmpValue
Call SetThreadPriority(mThreadHandle, tmpValue)
End Property

Public Property Get Enabled() As Boolean
'Returns whether the Thread is enabled or not
Enabled = mEnabled
End Property

Public Property Let Enabled(ByVal tmpValue As Boolean)
'Enables/Disables the Thread

'Ignore errors to prevent crashing if no thread has been created
On Error Resume Next
If tmpValue = True Then
'Enable the thread
Call ResumeThread(mThreadHandle)
ElseIf tmpValue = False Then
'Disable the thread
Call SuspendThread(mThreadHandle)
End If
End Property

Private Sub Class_Terminate()
'Terminate the thread to prevent crashing if the app is closed
'and the thread is still running (dangerous!)
Call TerminateCurrentThread
End Sub

laojing1128 2002-09-03

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见帮助中的coffe,thread

lihongxing2002 2002-09-03

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我也要，supperman_2002@sina.com
谢谢了谢谢了谢谢了谢谢了谢谢了谢谢了谢谢了谢谢了谢谢了谢谢了谢谢了谢谢了谢谢了！！！！！！！！！！！！！！！11

vb实现多线程的问题？？？

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