c++在矩形窗口中插入数字

您可以使用图形库来在矩形窗口中插入数字。以下是一个使用 WinAPI 的示例代码：

#include <windows.h>
#include <iostream>
#include <string>

LRESULT CALLBACK WindowProcedure(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR args, int ncmdshow)
{
    WNDCLASSW wc = {0};

    wc.hbrBackground = (HBRUSH)COLOR_WINDOW;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hInstance = hInst;
    wc.lpszClassName = L"myWindowClass";
    wc.lpfnWndProc = WindowProcedure;

    if(!RegisterClassW(&wc))
        return -1;

    HWND hwnd = CreateWindowW(L"myWindowClass", L"Window Title", WS_OVERLAPPEDWINDOW | WS_VISIBLE, 100, 100, 500, 500, NULL, NULL, NULL, NULL);

    MSG msg = {0};

    while(GetMessage(&msg, NULL, NULL, NULL))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return 0;
}

LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp)
{
    switch(msg)
    {
        case WM_DESTROY:
            PostQuitMessage(0);
            break;

        case WM_PAINT:
        {
            PAINTSTRUCT ps;
            HDC hdc = BeginPaint(hwnd, &ps);

            // 选择字体和颜色
            HFONT hFont = CreateFont(16, 0, 0, 0, FW_NORMAL, FALSE, FALSE, FALSE, ANSI_CHARSET, OUT_DEFAULT_PRECIS,
                                     CLIP_DEFAULT_PRECIS, DEFAULT_QUALITY, DEFAULT_PITCH | FF_SWISS, L"Arial");
            SelectObject(hdc, hFont);
            SetTextColor(hdc, RGB(0, 0, 0));

            // 绘制矩形框
            RECT rect = {50, 50, 250, 150};
            DrawEdge(hdc, &rect, EDGE_RAISED, BF_RECT);

            // 插入数字
            std::wstring text = L"123";
            DrawTextW(hdc, text.c_str(), -1, &rect, DT_SINGLELINE | DT_CENTER | DT_VCENTER);

            EndPaint(hwnd, &ps);
        }
        break;

        default:
            return DefWindowProcW(hwnd, msg, wp, lp);
    }

    return 0;
}

该代码将创建一个带有矩形框和数字的窗口。您可以更改 `text` 变量的值来插入不同的数字。请注意，这仅是一个示例代码，您可以根据需要进行修改和扩展。