首页 | 社区 | 博客 | 招聘 | 文章 | 新闻 | 下载 | 读书 | 代码
亲,您未登录哦! 登录 | 注册

Windows的多线程程序设计初步

打印文章

分享到:
  一般情况下多线程编程多采用MFC类库实现,那么如果不使用MFC 如何进行多线程程序设计呢?本文将就这个问题进行讨论:

  微软在Windows API中提供了建立新的线程的函数CreateThread,它的语法如下:

hThread = CreateThread (&security_attributes, dwStackSize, ThreadProc,pParam, dwFlags, &idThread) ;

  第一个参数是指向SECURITY_ATTRIBUTES型态的结构的指针。在Windows 98中忽略该参数。在Windows NT中,它被设为NULL。第二个参数是用于新线程的初始堆栈大小,默认值为0。在任何情况下,Windows根据需要动态延长堆栈的大小。

  CreateThread的第三个参数是指向线程函数的指标。函数名称没有限制,但是必须以下列形式声明:

DWORD WINAPI ThreadProc (PVOID pParam) ;
 
  CreateThread的第四个参数为传递给ThreadProc的参数。这样主线程和从属线程就可以共享数据。

  CreateThread的第五个参数通常为0,但当建立的线程不马上执行时为旗标CREATE_SUSPENDED。线程将暂停直到呼叫ResumeThread来恢复线程的执行为止。第六个参数是一个指标,指向接受执行绪ID值的变量。

  大多数Windows程序写作者喜欢用在PROCESS.H表头文件中声明的C执行时期链接库函数_beginthread。它的语法如下:

hThread = _beginthread (ThreadProc, uiStackSize, pParam) ;

  它更简单,对于大多数应用程序很完美,这个线程函数的语法为:

void __cdecl ThreadProc (void * pParam) ;

  在建立多线程的Windows程序时,需要在「Project Settings」对话框中做一些修改。选择「C/C++」页面标签,然后在「Category」下拉式清单方块中选择「Code Generation」。在「Use Run-Time Library」下拉式清单方块中,可以看到用于「Release」设定的「Single-Threaded」和用于Debug设定的「Debug Single-Threaded」。将这些分别改为「Multithreaded」和「Debug Multithreaded」。这将把编译器旗标改为/MT,它是编译器在编译多线程的应用程序所需要的。

  第一个demo.

/*******************************************************
*
* deom1---四个线程同时写一个文件( 没有参数 )
*
*
***********************************************************/
#include <windows.h>
#include <process.h> /* _beginthread, _endthread */
#include <iostream>
#include <fstream>
using namespace std;

ofstream out("out.txt");

void ThreadFunc1(PVOID param)
{
 while(1)
 {
  Sleep(10);
  out<<"This was draw by thread l"<<endl;
 }
}
void ThreadFunc2(PVOID param)
{
 while(1)
 {
  Sleep(10);
  out<<"This was draw by thread 2"<<endl;
 }
}
void ThreadFunc3(PVOID param)
{
 while(1)
 {
  Sleep(10);
  out<<"This was draw by thread 3"<<endl;
 }
}
void ThreadFunc4(PVOID param)
{
 while(1)
 {
  Sleep(10);
  out<<"This was draw by thread 4"<<endl;
 }
}
int main()
{
 int i=0;
 _beginthread(ThreadFunc1,0,NULL);
 _beginthread(ThreadFunc2,0,NULL);

 _beginthread(ThreadFunc3,0,NULL);
 _beginthread(ThreadFunc4,0,NULL);
 Sleep(3000);
 out<<"end";
 return 0;
}

//demo1 end-----------------------------------------------

第二个demo.
/*******************************************************
*
* deom2---四个线程同时写一个文件( 有参数 )
*
*
***********************************************************/
#include <windows.h>
#include <process.h> /* _beginthread, _endthread */
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
ofstream out("out.txt");

void ThreadFunc1(PVOID param)
{
 while(1)
 {
  char *p;
  p=(char *) param;
  Sleep(10);
  out<<p<<"This was draw by thread l"<<endl;
 }
}
void ThreadFunc2(PVOID param)
{
 while(1)
 {
  Sleep(10);
  out<<"This was draw by thread 2"<<endl;
 }
}
void ThreadFunc3(PVOID param)
{
 while(1)
 {
  Sleep(10);
  out<<"This was draw by thread 3"<<endl;
 }
}
void ThreadFunc4(PVOID param)
{
 while(1)
 {
  Sleep(10);
  out<<"This was draw by thread 4"<<endl;
 }
}
int main()
{
 char *pstr=" 参数传递成功";

 _beginthread(ThreadFunc1,0,pstr);
 _beginthread(ThreadFunc2,0,NULL);

 _beginthread(ThreadFunc3,0,NULL);
 _beginthread(ThreadFunc4,0,NULL);
 Sleep(1000);
 out<<"end";
 return 0;
}

// demo2 end ------------------------------------------------

第三个demo( 一个win32 应用程序 )

/*******************************************************
*
* deom3--- 在屏幕上随机画出一系列矩形
*
*
***********************************************************/


#include <windows.h>
#include <process.h>

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
HWND hwnd ;

int cxClient, cyClient ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,

PSTR szCmdLine, int iCmdShow)
{
 static TCHAR szAppName[] = TEXT ("RndRctMT") ;
  MSG msg ;

WNDCLASS wndclass ;

wndclass.style = CS_HREDRAW | CS_VREDRAW ;
wndclass.lpfnWndProc = WndProc ;
wndclass.cbClsExtra = 0 ;
wndclass.cbWndExtra = 0 ;
wndclass.hInstance = hInstance ;
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ;
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;
wndclass.lpszClassName = szAppName ;

if (!RegisterClass (&wndclass))
{
 MessageBox (NULL, TEXT ("This program requires Windows NT!"),szAppName, MB_ICONERROR) ;
 return 0 ;
}

hwnd = CreateWindow ( szAppName, TEXT ("Random Rectangles"),
  WS_OVERLAPPEDWINDOW,
  CW_USEDEFAULT, CW_USEDEFAULT,
  CW_USEDEFAULT, CW_USEDEFAULT,
  NULL, NULL, hInstance, NULL) ;
ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;

while (GetMessage (&msg, NULL, 0, 0))
{
 TranslateMessage (&msg) ;
 DispatchMessage (&msg) ;
}
return msg.wParam ;
}

VOID Thread (PVOID pvoid)
{
 HBRUSH hBrush ;
 HDC hdc ;
 int xLeft, xRight, yTop, yBottom, iRed, iGreen, iBlue ;

 while (TRUE)
 {
  if (cxClient != 0 || cyClient != 0)
  {
   xLeft = rand () % cxClient ;
   xRight = rand () % cxClient ;
   yTop = rand () % cyClient ;
   yBottom = rand () % cyClient ;
   iRed = rand () & 255 ;
   iGreen = rand () & 255 ;
   iBlue = rand () & 255 ;
 
   hdc = GetDC (hwnd) ;
   hBrush = CreateSolidBrush (RGB (iRed, iGreen, iBlue)) ;
   SelectObject (hdc, hBrush) ;

   Rectangle (hdc,min (xLeft, xRight), min (yTop, yBottom),
     max (xLeft, xRight), max (yTop, yBottom)) ;

   ReleaseDC (hwnd, hdc) ;
   DeleteObject (hBrush) ;
  }
 }
}

LRESULT CALLBACK WndProc ( HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
 switch (message)
 {
  case WM_CREATE:
   _beginthread (Thread, 0, NULL) ;
   return 0 ;
  case WM_SIZE:
   cxClient = LOWORD (lParam) ;
   cyClient = HIWORD (lParam) ;
   return 0 ;
  case WM_DESTROY:
   PostQuitMessage (0) ;
   return 0 ;
 }
 return DefWindowProc (hwnd, message, wParam, lParam) ;
}

//demo4 end-----------------------------------------------


  参考:windows 程序设计 

本栏文章均来自于互联网,版权归原作者和各发布网站所有,本站收集这些文章仅供学习参考之用。任何人都不能将这些文章用于商业或者其他目的。( Pfan.cn )

编程爱好者论坛

本栏最新文章