c++-cli - CLI/C++ 如何获取窗口句柄？

Question

我需要获取另一个窗口的句柄。

这是它的代码:

private: System::Void btn_find_Click(System::Object^  sender, System::EventArgs^  e) {
             array<Process^>^ ps = Process::GetProcessesByName("Notepad");
             IntPtr X = ps[0]->MainWindowHandle;
             LPRECT rect;
             if (GetWindowRect(static_cast<HWND>(X.ToPointer()), rect)){
                 DEBUGBOX->Text = "OK!";
             }
             else
             {
                 //DEBUGBOX is a text box
                 DEBUGBOX->Text = ps[0]->MainWindowTitle;

                 //the following code is from MSDN, it is used to
                 //show a message box about the error
                 //P.S. I have no idea why it has to be this complicated
                 LPVOID lpMsgBuf;
                 LPVOID lpDisplayBuf;
                 DWORD dw = GetLastError();
                 LPTSTR lpszFunction = TEXT("GetWindowRect");
                 FormatMessage(
                     FORMAT_MESSAGE_ALLOCATE_BUFFER |
                     FORMAT_MESSAGE_FROM_SYSTEM |
                     FORMAT_MESSAGE_IGNORE_INSERTS,
                     NULL,
                     dw,
                     MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
                     (LPTSTR)&lpMsgBuf,
                     0, NULL);
                 lpDisplayBuf = (LPVOID)LocalAlloc(LMEM_ZEROINIT,
                     (lstrlen((LPCTSTR)lpMsgBuf) + lstrlen((LPCTSTR)lpszFunction) + 40) * sizeof(TCHAR));
                 StringCchPrintf((LPTSTR)lpDisplayBuf,
                     LocalSize(lpDisplayBuf) / sizeof(TCHAR),
                     TEXT("%s failed with error %d: %s"),
                     lpszFunction, dw, lpMsgBuf);
                 using MessageBox = System::Windows::Forms::MessageBox;
                 MessageBox::Show(gcnew System::String((LPCTSTR)lpDisplayBuf));
                 LocalFree(lpMsgBuf);
                 LocalFree(lpDisplayBuf);
             }
}

目前它可以毫无问题地找到“记事本”进程，但是GetWindowRect函数会失败，并转到繁琐的错误信息处理代码，给我“error 1400: Invalid window handle ".

我进行了一些搜索，但找不到它不起作用的原因。我怀疑 IntPtr 到 HWND 的 static_cast，代码来自互联网，但看起来是合法的。

我还需要句柄来进行一些后续操作。

Answer 1

如果你知道窗口标题栏的名称然后尝试FindWindowA

HWND handle;
handle=FindWindowA(NULL, "Calculator");

https://msdn.microsoft.com/en-us/library/windows/desktop/ms633499(v=vs.85).aspx