如何使用C++确定应用程序是否已在窗口中启动?

How to determine an application is already launched or not in windows using C++?

本文关键字：窗口 启动 是否 C++ 何使用 应用程序      更新时间：2023-10-16

我正在启动一个Windows桌面应用程序 CATStartProcess (const char *comPath， char *const argv[]， int wait， int *pid， int *exitStatus(; 参数将传递给它。 如果应用程序已经在运行，则无需为此创建新实例。如何检查此应用程序是否已在后台运行？

int wait = 0;   
int pid;
int exitStatus;
char *CommandArgs[9] = { 0 };
CommandArgs[0] = (char*)usComposerExePath.ConvertToChar();
CommandArgs[1] = (char*)usOpen.ConvertToChar();
CommandArgs[2] = (char*)usComposerProjectDocPath.ConvertToChar();
CommandArgs[3] = (char*)strInfiniteTicket.ConvertToChar();
CommandArgs[4] = (char*)strDocName.ConvertToChar();
CommandArgs[5] = (char*)strSecurityContext.ConvertToChar();     
CommandArgs[6] = (char*)usBusID.ConvertToChar();
CommandArgs[7] = (char*)usUserID.ConvertToChar();
CommandArgs[8] = NULL;
CATLibStatus startComposerBatchStatus = CATStartProcess((char*)usComposerExePath.ConvertToChar(), CommandArgs, wait, &pid, &exitStatus);

有几种方法，但我承认，我的两个解决方案都不是便携式/标准C++，但你标记了 Windows，所以我会给出一个 Windows 方法。

下面的代码实际上执行这两项检查。第一种方法是使用命名互斥锁。Windows有一个"全局"互斥锁，它检查任何用户正在运行的进程。如果互斥锁已存在，则其正在运行。如果它不存在，则它没有运行。在某些状态下，事情不容易确定，因此它会检查正在运行的进程列表。这部分不太准确，因为不同的权限会影响列表。

仅当您可以修改尝试启动的应用程序以创建互斥锁时，具有互斥锁的部分才有效。

#define WIN32_LEAN_AND_MEAN
#include <Windows.h>
#include <psapi.h>
#include <TlHelp32.h>
#include <shellapi.h>
#include <advpub.h>
enum class ProcessRunningState {
YES,
NO,
ERR
};
ProcessRunningState CheckIfProcessIsAlreadyRunning( DWORD currentProcessId, const wchar_t *programName, const wchar_t *programGUID, HANDLE *mutex_handle ) noexcept {
{ // Check the mutexes first
wchar_t global_prog_name[1024] = L"Global\";
wcsncat_s( global_prog_name, programName, wcslen( programGUID ) );

if ( mutex_handle ) {
*mutex_handle = CreateMutex( NULL, TRUE, global_prog_name );
if ( !( *mutex_handle ) ) {
const DWORD dw = GetLastError();
if ( dw == ERROR_ALREADY_EXISTS )
return ProcessRunningState::YES;
} else {
return ProcessRunningState::NO;
}
} else {
HANDLE h = OpenMutex( SYNCHRONIZE, FALSE, global_prog_name );
if ( h ) {
CloseHandle( h );
return ProcessRunningState::YES;
} else if ( GetLastError() == ERROR_FILE_NOT_FOUND ) {
return ProcessRunningState::NO;
}
}
}
{ // At this point, the state is unknown, so try running through the process list
DWORD aProcesses[2048], cProcesses;
if ( !EnumProcesses( aProcesses, sizeof( aProcesses ), &cProcesses ) ) {
return ProcessRunningState::ERR;
}
// Calculate how many process identifiers were returned.
cProcesses = cProcesses / sizeof( DWORD );
for ( unsigned int i = 0; i < cProcesses; i++ ) {
if ( aProcesses[i] != 0 && aProcesses[i] != currentProcessId ) {
HANDLE hProcess = OpenProcess( PROCESS_QUERY_INFORMATION | PROCESS_VM_READ, FALSE, aProcesses[i] );
WCHAR szProcessName[MAX_PATH] = { 0 };
if ( hProcess ) {
HMODULE hMod;
DWORD cbNeeded;
if ( EnumProcessModules( hProcess, &hMod, sizeof( hMod ), &cbNeeded ) ) {
GetModuleBaseName( hProcess, hMod, szProcessName, sizeof( szProcessName ) / sizeof( TCHAR ) ); // Can't error here, since this function "errors" on access
}/* else {
return ProcessRunningState::ERR;
}*/
CloseHandle( hProcess );
}
if ( _wcsicmp( szProcessName, programName ) == 0 ) {
return ProcessRunningState::YES;
}
}
}
}
return ProcessRunningState::NO;
}

如果可能的话，这样称呼它会创建互斥锁，并且基本上是说"我想跑，可以吗？

HANDLE mutex_handle;
const ProcessRunningState cur_state = CheckIfProcessIsAlreadyRunning( GetCurrentProcessId(), L"PROGRAM_NAME", programGUID, &mutex_handle );
switch ( cur_state ) {
case ProcessRunningState::ERR:
case ProcessRunningState::YES:
return ERROR_ALREADY_EXISTS;
default:
break;
}

像这样调用它，只需检查它是否已经在运行，如果没有，则启动应用程序。

if ( CheckIfProcessIsAlreadyRunning( GetCurrentProcessId(), L"PROGRAM_NAME", programGUID, nullptr ) == ProcessRunningState::NO ) {
std::wstring programInstallLocation = L"path";
std::wstring programName = programInstallLocation + L"\PROGRAM_NAME";
ShellExecute( NULL, L"open", programName.c_str(), NULL, NULL, SW_SHOW );
}

在代码中的某个地方，您将指定programGUID是什么。例如：

WCHAR programGUID[] = L"ba2e95a0-9168-4b6e-bcd6-57309748df21";
相关文章：