Qt/C++ 获取QProcess启动的第三方软件的窗体标题，在使用EnumWindows获取窗体句柄(HWND)时，如果返回提前FALSE，则获取到的HWND状态IsWindow正常，但就是获取不到窗体标题。必须正常返回TRUE才能使用HWND获取到窗体标题，要不然获取到的标题内容就是空。

QProcess线程需要在启动后等待几秒的时间再获取打开的窗体句柄，或者一直While(true)获取窗体句柄直到获取HWND不为空为止。

使用EnumWindows获取所有窗体句柄和PID

写法1

static HWND GHO_HWMD_C=nullptr;
static BOOL CALLBACK EnumChildProc(HWND hwnd, LPARAM lParam)
{DWORD processId;GetWindowThreadProcessId(hwnd, &processId);if (processId == (DWORD)lParam){GHO_HWMD_C=hwnd;}///必须返回true 如果返回false 会造成HWND不能获取窗体标题，修改窗体隐藏等属性return TRUE;
}static BOOL CALLBACK EnumThreadChildProc(HWND hwnd, LPARAM lParam)
{DWORD processId;GetWindowThreadProcessId(hwnd, &processId);if (processId == (DWORD)lParam){GHO_HWMD_C=hwnd;}///必须返回true 如果返回false 会造成HWND不能获取窗体标题，修改窗体隐藏等属性return TRUE;
}static BOOL CALLBACK EnumWindowsProc(HWND hwnd, LPARAM lParam)
{DWORD processId;GetWindowThreadProcessId(hwnd, &processId);if (processId == (DWORD)lParam){GHO_HWMD_C=hwnd;}///必须返回true 如果返回false 会造成HWND不能获取窗体标题，修改窗体隐藏等属性return TRUE;EnumChildWindows(hwnd, EnumChildProc, lParam);EnumThreadWindows(processId,EnumThreadChildProc, lParam);
}//在所有线程中查找pid
//process.processId(); QProcess类processId()返回pid
EnumWindows(EnumWindowsProc, (LPARAM)process.processId());

写法2

EnumWindows([](HWND hwndparent, LPARAM lParam)->BOOL{DWORD processId = 0;GetWindowThreadProcessId(hwndparent, &processId);if (processId == (DWORD)lParam){GHO_HWMD_C=hwnd;}EnumChildWindows(hwndparent,[](HWND Chwnd, LPARAM lParam)->BOOL{DWORD CprocessId = 0;GetWindowThreadProcessId(Chwnd, &CprocessId);if (CprocessId == (DWORD)lParam){GHO_HWMD_C=hwnd;}return TRUE; // 返回TRUE以继续枚举下一个窗体},lParam);EnumThreadWindows(processId,[](HWND Thwnd, LPARAM lParam)->BOOL{DWORD TprocessId = 0;GetWindowThreadProcessId(Thwnd, &TprocessId);if (TprocessId == (DWORD)lParam){GHO_HWMD_C=hwnd;}return TRUE; // 返回TRUE以继续枚举下一个窗体},lParam);return TRUE; // 返回TRUE以继续枚举下一个窗体},(LPARAM)process.processId());

获取窗体标题

使用 GetWindowTextA 获取窗体标题

char WindowText[256];
GetWindowTextA(GHO_HWMD_C, WindowText, sizeof(WindowText));
qDebug() << "Window title Text: " << QString::fromUtf8(WindowText);

使用 SendMessage获取窗体标题

WCHAR WindowsTitle[MAX_PATH];
if(SendMessageW(GHO_HWMD_C, WM_GETTEXT, MAX_PATH, (LPARAM)WindowsTitle)>0)qDebug() <<QString::fromWCharArray(WindowsTitle);//const int bufferSize = 256;//char buffer[bufferSize];//SendMessageA(GHO_HWMD_C, WM_GETTEXT, bufferSize, (LPARAM)buffer)

使用 DefWindowProcA获取窗体标题

int len = SendMessageA(GHO_HWMD_C, WM_GETTEXTLENGTH, 0, 0) + 1;
// new一块len大小的内存
char *title = new char(len);
// 初始化内存为0
memset(title, 0, len);
// 发送WM_GETTEXT消息获取控件文本
DefWindowProcA(GHO_HWMD_C, WM_GETTEXT, 1024, (LPARAM)title);

使用 GetClassNameA获取窗体类名称

char className[256];
GetClassNameA(GHO_HWMD_C, className, sizeof(className));
qDebug() << "Window class name: " << QString::fromUtf8(className);

使用FindWindowEx获取窗体句柄

/*! https://linuxcpp.0voice.com/?id=132468*/
/*!
int main(int argc, char *argv[])
{QCoreApplication a(argc, argv);QProcess process;process.start("path/to/your/executable");if (process.waitForStarted()){// 获取进程IDDWORD pid = process.processId();// 获取进程主窗口句柄HWND hwnd = nullptr;do{hwnd = FindWindowEx(nullptr, hwnd, nullptr, nullptr);DWORD windowPid;GetWindowThreadProcessId(hwnd, &windowPid);if (windowPid == pid){// 获取窗口类名char className[256];GetClassName(hwnd, className, sizeof(className));qDebug() << "Window class name: " << QString::fromUtf8(className);break;}} while (hwnd != nullptr);process.waitForFinished();}return a.exec();
}*/