MFC对话框程序只运行单个实例 的简单示例

作者：虚坏叔叔

MFC程序只运行单个实例 的简单示例

这里只是简单的建立一个​​MFC​​ 程序来演示 只运行一个实例。

一、在头文件中添加类似如下代码

#define SCANSETTINGS_CLASSNAME _T("ScanSettingsWindowClass")
#define APPMUTEX _T("Global\\ScanSettings")

 virtual int ExitInstance();
private:
 HANDLE m_hMutex;
 // Implementation 
 BOOL RestrictOneInstance();

二、在源文件中添加如下代码

BOOL CXXXApp::InitInstance()
{
 // Begin.  把这段代码加在最前面即可
 if (!RestrictOneInstance())
 {
  return FALSE;
 }

 WNDCLASS wc;
 ::GetClassInfo(AfxGetInstanceHandle(), _T("#32770"), &wc);
 wc.lpszClassName = SCANSETTINGS_CLASSNAME;
 AfxRegisterClass(&wc);
 // End

//...........................

}


BOOL CXXXApp::RestrictOneInstance()
{
 SECURITY_DESCRIPTOR secutityDese;
 ::InitializeSecurityDescriptor(&secutityDese, SECURITY_DESCRIPTOR_REVISION);
 ::SetSecurityDescriptorDacl(&secutityDese, TRUE, NULL, FALSE);

 SECURITY_ATTRIBUTES securityAttr;
 securityAttr.nLength = sizeof SECURITY_ATTRIBUTES;
 securityAttr.bInheritHandle = FALSE;
 securityAttr.lpSecurityDescriptor = &secutityDese;

 m_hMutex = ::CreateMutex(&securityAttr, FALSE, APPMUTEX);
 BOOL bLaunched = (m_hMutex != NULL && ERROR_ALREADY_EXISTS == GetLastError());

 CWnd *pWndPrev = NULL;
 CWnd *pWndChild = NULL;

 if (pWndPrev == NULL)
 {
  pWndPrev = CWnd::FindWindow(SCANSETTINGS_CLASSNAME, NULL);
 }

 if (pWndPrev != NULL)
 {
  // If so, does it have any popups?
  pWndChild = pWndPrev->GetLastActivePopup();

  // If iconic, restore the main window
  if (pWndPrev->IsIconic())
  {
   pWndPrev->ShowWindow(SW_RESTORE);
  }

  // Bring the main window or its popup to
  // the foreground
  pWndChild->SetForegroundWindow();

  return FALSE;
 }

 return TRUE;
}


int CXXXApp::ExitInstance()
{
 // TODO: Add your specialized code here and/or call the base class
 if (m_hMutex != NULL)
 {
  CloseHandle(m_hMutex);
  m_hMutex = NULL;
 }

 return CWinApp::ExitInstance();
}

三、在资源脚本中也应修改

IDD_XXX_DIALOG DIALOGEX 0, 0, 331, 151
STYLE DS_SETFONT | DS_FIXEDSYS | WS_POPUP | WS_VISIBLE | WS_CAPTION | WS_SYSMENU | WS_THICKFRAME
EXSTYLE WS_EX_APPWINDOW
CAPTION "XXXXXXXXXX"
CLASS "ScanSettingsWindowClass"  //添加这句
FONT 8, "MS Shell Dlg", 0, 0, 0x1
BEGIN
    LTEXT           "",IDC_STATIC1,0,0,330,129,0,WS_EX_TRANSPARENT
    PUSHBUTTON      "重签",IDC_BUTTON1,71,132,62,19
    PUSHBUTTON      "确定",IDC_BUTTON2,175,132,62,19
END

四、总结

• 本文完成MFC程序只运行单个实例 的简单示例。
• 如果觉得文章对你有用处，记得​​点赞​​​​收藏​​​​转发​​ 一波哦，博主也支持为铁粉丝制作专属动态壁纸哦~