Курсовая работа: Потоки в Visual Basic

Функция StartBackgroundThreadFree определена в модуле modMTBack следующим образом:

Declare Function CreateThread Lib "kernel32" _

(ByVal lpSecurityAttributes As Long, ByVal _

dwStackSize As Long, ByVal lpStartAddress As Long, _

ByVal lpParameter As Long, ByVal dwCreationFlags _

As Long, lpThreadId As Long) As Long

Declare Function CloseHandle Lib "kernel32" _

(ByVal hObject As Long) As Long

' Start the background thread for this object

' using the invalid free threading approach.

Public Function StartBackgroundThreadFree (ByVal qobj As clsBackground)

Dim threadid As Long

Dim hnd&

Dim threadparam As Long

' Free threaded approach

threadparam = ObjPtr(qobj)

hnd = CreateThread(0, 2000, AddressOf _

BackgroundFuncFree, threadparam, 0, threadid)

If hnd = 0 Then

' Return with zero (error)

Exit Function

End If

' We don't need the thread handle

CloseHandle hnd

StartBackgroundThreadFree = threadid

End Function

Функция CreateThread имеетшестьпараметров:

lpSecurityAttributes - обычно устанавливается в нуль, чтобы использовать заданные по умолчанию атрибуты защиты.

dwStackSize - размер стека. Каждый поток имеет собственный стек.