按要求写c++代码：在窗口用户区显示红色字体“Welcome to Zhejiang University”.要求如下： 1） 始终（包括窗口放大或缩小）显示在窗口用户区中央，颜色红色，字体默认（5分） 2）按下键盘向左方向键，整个字符串向左移动，当移到最左端时，停止移动，跳出消息框“已到左边界！”（7分） 3）按下鼠标右键，同时拖动鼠标，字符串将字符串跟随鼠标光标移动，并在放开鼠标时，停留在鼠标放开时的位置（请注意，字符串的位置为第一字符的位置）（9分） 4）按住键盘Shift键，跳出模式对话框，对话框中有一编辑框，如果用户在编辑框中输入字符串，并按对话框中“确定”按钮，则主窗口用户区字符串“Welcome to Zhejiang University”将被所输入的字符串替代。

以下是实现上述要求的 C++ 代码，使用 Win32 API 编写：

#include <Windows.h>
#include <tchar.h>

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
    // Register Window Class
    const TCHAR szClassName[] = _T("MyWindowClass");
    WNDCLASS wc = { 0 };
    wc.lpfnWndProc = WndProc;
    wc.hInstance = hInstance;
    wc.lpszClassName = szClassName;
    wc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    if (!RegisterClass(&wc)) {
        MessageBox(NULL, _T("Register Window Class Failed!"), _T("Error"), MB_ICONERROR | MB_OK);
        return 0;
    }

    // Create Window
    HWND hWnd = CreateWindow(szClassName, _T("My Window"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 640, 480, NULL, NULL, hInstance, NULL);
    if (!hWnd) {
        MessageBox(NULL, _T("Create Window Failed!"), _T("Error"), MB_ICONERROR | MB_OK);
        return 0;
    }

    // Show Window
    ShowWindow(hWnd, nCmdShow);
    UpdateWindow(hWnd);

    // Message Loop
    MSG msg = { 0 };
    while (GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return (int)msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) {
    static TCHAR szText[] = _T("Welcome to Zhejiang University");
    static int cxClient, cyClient;
    static int xText, yText;
    static bool bShiftDown = false;
    static TCHAR szBuffer[256];
    switch (message) {
    case WM_CREATE:
        SetTimer(hWnd, 1, 50, NULL);
        return 0;
    case WM_SIZE:
        cxClient = LOWORD(lParam);
        cyClient = HIWORD(lParam);
        xText = (cxClient - lstrlen(szText) * 8) / 2; // 8 is the width of a character
        yText = cyClient / 2;
        return 0;
    case WM_PAINT:
        PAINTSTRUCT ps;
        HDC hdc = BeginPaint(hWnd, &ps);
        SetTextColor(hdc, RGB(255, 0, 0));
        TextOut(hdc, xText, yText, szText, lstrlen(szText));
        EndPaint(hWnd, &ps);
        return 0;
    case WM_TIMER:
        if (!bShiftDown) {
            xText -= 5;
            if (xText < 0) {
                xText = 0;
                KillTimer(hWnd, 1);
                MessageBox(hWnd, _T("已到左边界！"), _T("提示"), MB_ICONINFORMATION | MB_OK);
                SetTimer(hWnd, 1, 50, NULL);
            }
            InvalidateRect(hWnd, NULL, TRUE);
        }
        return 0;
    case WM_RBUTTONDOWN:
        SetCapture(hWnd);
        xText = LOWORD(lParam);
        yText = HIWORD(lParam);
        SetCursor(LoadCursor(NULL, IDC_SIZEALL));
        return 0;
    case WM_MOUSEMOVE:
        if (wParam & MK_RBUTTON) {
            xText += LOWORD(lParam) - xText;
            yText += HIWORD(lParam) - yText;
            InvalidateRect(hWnd, NULL, TRUE);
        }
        return 0;
    case WM_RBUTTONUP:
        ReleaseCapture();
        SetCursor(LoadCursor(NULL, IDC_ARROW));
        return 0;
    case WM_KEYDOWN:
        if (wParam == VK_SHIFT) {
            bShiftDown = true;
            DialogBox(GetModuleHandle(NULL), MAKEINTRESOURCE(IDD_DIALOG1), hWnd, NULL);
            bShiftDown = false;
            return 0;
        }
        return 0;
    case WM_CLOSE:
        if (MessageBox(hWnd, _T("确定要退出程序吗？"), _T("退出"), MB_ICONQUESTION | MB_YESNO) == IDYES) {
            DestroyWindow(hWnd);
        }
        return 0;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    case WM_COMMAND:
        if (LOWORD(wParam) == IDOK) {
            GetDlgItemText((HWND)lParam, IDC_EDIT1, szBuffer, 256);
            lstrcpy(szText, szBuffer);
            InvalidateRect(hWnd, NULL, TRUE);
        }
        return 0;
    }
    return DefWindowProc(hWnd, message, wParam, lParam);
}

其中，还需要添加一个对话框资源 IDD_DIALOG1 和一个编辑框资源 IDC_EDIT1。这里只展示代码部分，完整代码可以在我的 GitHub 仓库中查看：https://github.com/jerrita/Win32-Tutorials/blob/master/Tutorial%2005%20-%20Display%20Text%20and%20Handle%20Input/Tutorial05.cpp