DX9从全屏切换到窗口，给出了错误的客户端区域

在我的DX9应用程序中有一些问题。当我使用客户端区域下方的代码从全屏切换到窗口模式不是正确的尺寸时，它较小。调整WindowRect函数正在正确执行任务，但SetWindowPos没有设置正确的窗口大小。也许我错过了一些东西。任何想法。

if (d3dpp.Windowed && resChoice == resolutionchoice) return false; // already in window mode and same resolution
                                    //MessageBox(NULL, L"switching to window", L"ERROR", MB_OK);
        resChoice = resolutionchoice;
        screenWidth = resolutionwidth[resChoice];
        screenHeight = resolutionheight[resChoice];
        d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;    // set the back buffer format to 32-bit
        d3dpp.BackBufferWidth = screenWidth;    // set the width of the buffer
        d3dpp.BackBufferHeight = screenHeight;    // set the height of the buffer
        d3dpp.Windowed = true;
        SetWindowLong(hWnd, GWL_STYLE, WS_OVERLAPPEDWINDOW); // WS_CAPTION | WS_SYSMENU | WS_VISIBLE | WS_MINIMIZEBOX );
        // need to call SetWindowPos as well
        string values;
        RECT r = { 0,0,screenWidth,screenHeight };
        AdjustWindowRect(&r, WS_OVERLAPPEDWINDOW, false);
        values = std::to_string(r.left);
        OutputDebugStringA("Adjust area = ");
        OutputDebugStringA(values.c_str()); OutputDebugStringA(",");
        values = std::to_string(r.top);
        OutputDebugStringA(values.c_str()); OutputDebugStringA(",");
        values = std::to_string(r.right);
        OutputDebugStringA(values.c_str()); OutputDebugStringA(",");
        values = std::to_string(r.bottom);
        OutputDebugStringA(values.c_str()); OutputDebugStringA("n"); 
        SetWindowPos(hWnd, HWND_TOP, r.left, r.top, r.right - r.left , r.bottom - r.top,  SWP_NOZORDER | SWP_SHOWWINDOW | SWP_FRAMECHANGED);//
        //screenWidth = SCREEN_WIDTH;
        //screenHeight = SCREEN_HEIGHT;
        //windowXscale = 1;
        //windowYscale = 1;
        GetClientRect(hWnd, &r);
        values = std::to_string(r.left);
        OutputDebugStringA("Client area = ");
        OutputDebugStringA(values.c_str()); OutputDebugStringA(",");
        values = std::to_string(r.top);
        OutputDebugStringA(values.c_str()); OutputDebugStringA(",");
        values = std::to_string(r.right);
        OutputDebugStringA(values.c_str()); OutputDebugStringA(",");
        values = std::to_string(r.bottom);
        OutputDebugStringA(values.c_str()); OutputDebugStringA("n");
    }