多线程(四)多线程同步_Critical Section临界区

1 int g_nTickNum = 10; //总票数
2 CEdit* g_editShowInfo; //编辑框控件指针
3 CRITICAL_SECTION g_cs; //临界区对象
4 
5 //线程函数前置声明
6 DWORD WINAPI ThreadSellTicket_One(LPVOID lpParam);
7 DWORD WINAPI ThreadSellTicket_Two(LPVOID lpParam);
8 DWORD WINAPI ThreadSellTicket_Three(LPVOID lpParam);

 1 BOOL CCriticalSectionDemoDlg::OnInitDialog()
 2 {
 3     CDialogEx::OnInitDialog();
 4 
 5     // 设置此对话框的图标。当应用程序主窗口不是对话框时，框架将自动
 6     //  执行此操作
 7     SetIcon(m_hIcon, TRUE);            // 设置大图标
 8     SetIcon(m_hIcon, FALSE);        // 设置小图标
 9 
10     //初始化临界区
11     InitializeCriticalSection(&g_cs);
12     //获取EDIT控件指针，供线程内部访问
13     g_editShowInfo = (CEdit*)GetDlgItem(IDC_EDIT_SHOWINFO);
14 
15     return TRUE;  // 除非将焦点设置到控件，否则返回 TRUE
16 }

1 void CCriticalSectionDemoDlg::OnBnClickedBtnSellticket()
2 {
3     //创建三个售票窗口线程,创建后直接关闭句柄
4     CloseHandle(CreateThread(NULL,0,ThreadSellTicket_One,NULL,0,NULL));
5     CloseHandle(CreateThread(NULL,0,ThreadSellTicket_Two,NULL,0,NULL));
6     CloseHandle(CreateThread(NULL,0,ThreadSellTicket_Three,NULL,0,NULL));
7 }

 1 //线程_售票窗口1
 2 DWORD WINAPI ThreadSellTicket_One(LPVOID lpParam)
 3 {
 4     CString strEdit;
 5     CString strNew;
 6     while (true)
 7     {
 8         Sleep(1000);
 9         EnterCriticalSection(&g_cs);
10         g_editShowInfo->GetWindowText(strEdit);
11         if(g_nTickNum > 0)
12         {
13             strNew.Format(_T("线程1:剩余票数：%d,售出1张票\r\n"),g_nTickNum--);        
14             strEdit += strNew;
15             if(g_nTickNum == 0)
16             {
17                 strEdit += _T("线程1:票己售空，关闭售票窗口\r\n");
18                 g_editShowInfo->SetWindowText(strEdit);
19                 LeaveCriticalSection(&g_cs);
20                 break;
21             }
22             else
23             {
24                 g_editShowInfo->SetWindowText(strEdit);
25                 LeaveCriticalSection(&g_cs);
26             }
27         }
28         else
29         {
30             strEdit += _T("线程1:票己售空，关闭售票窗口\r\n");
31             g_editShowInfo->SetWindowTextW(strEdit);
32             LeaveCriticalSection(&g_cs);
33             break;
34         }
35     }
36     return true;
37 }

 1 DWORD WINAPI ThreadSellTicket_Two(LPVOID lpParam)
 2 {
 3     CString strEdit;
 4     CString strNew;
 5     while (true)
 6     {
 7         Sleep(1000);
 8         EnterCriticalSection(&g_cs);
 9         g_editShowInfo->GetWindowText(strEdit);
10         if(g_nTickNum > 0)
11         {
12             strNew.Format(_T("线程2:剩余票数：%d,售出1张票\r\n"),g_nTickNum--);        
13             strEdit += strNew;
14             if(g_nTickNum == 0)
15             {
16                 strEdit += _T("线程2:票己售空，关闭售票窗口\r\n");
17                 g_editShowInfo->SetWindowText(strEdit);
18                 LeaveCriticalSection(&g_cs);
19                 break;
20             }
21             else
22             {
23                 g_editShowInfo->SetWindowText(strEdit);
24                 LeaveCriticalSection(&g_cs);
25             }
26         }
27         else
28         {
29             strEdit += _T("线程2:票己售空，关闭售票窗口\r\n");
30             g_editShowInfo->SetWindowTextW(strEdit);
31             LeaveCriticalSection(&g_cs);
32             break;
33         }
34     }
35     return true;
36 }

 1 DWORD WINAPI ThreadSellTicket_Three(LPVOID lpParam)
 2 {
 3     CString strEdit;
 4     CString strNew;
 5     while (true)
 6     {
 7         Sleep(1000);
 8         EnterCriticalSection(&g_cs);
 9         g_editShowInfo->GetWindowText(strEdit);
10         if(g_nTickNum > 0)
11         {
12             strNew.Format(_T("线程3:剩余票数：%d,售出1张票\r\n"),g_nTickNum--);        
13             strEdit += strNew;
14             if(g_nTickNum == 0)
15             {
16                 strEdit += _T("线程3:票己售空，关闭售票窗口\r\n");
17                 g_editShowInfo->SetWindowText(strEdit);
18                 LeaveCriticalSection(&g_cs);
19                 break;
20             }
21             else
22             {
23                 g_editShowInfo->SetWindowText(strEdit);
24                 LeaveCriticalSection(&g_cs);
25             }
26         }
27         else
28         {
29             strEdit += _T("线程3:票己售空，关闭售票窗口\r\n");
30             g_editShowInfo->SetWindowTextW(strEdit);
31             LeaveCriticalSection(&g_cs);
32             break;
33         }
34     }
35     return true;
36 }

1 BOOL CCriticalSectionDemoDlg::DestroyWindow()
2 {
3     //删除临界区
4     DeleteCriticalSection(&g_cs);
5     return CDialogEx::DestroyWindow();
6 }