C++ WINAPI如何才能只运行一次鼠标事件？

#include <Windows.h>

bool isMouseEventExecuted = false;

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    switch (uMsg)
    {
        case WM_LBUTTONDOWN:
        {
            if (!isMouseEventExecuted)
            {
                // 执行鼠标事件的相关操作
                // ...

                isMouseEventExecuted = true;
            }
            break;
        }
        // 处理其他消息
        // ...
    }

    return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    // 创建窗口等初始化操作
    // ...

    // 注册窗口类
    // ...

    // 创建窗口
    // ...

    // 消息循环
    MSG msg;
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return 0;
}