C# 用全局钩子使鼠标按键左右键互换，鼠标移动反向相反

实现这个需求需要使用 C# 中的钩子函数来实现全局鼠标事件监听。具体步骤如下：

1. 引入 System.Runtime.InteropServices 命名空间。

2. 定义鼠标事件枚举类型：

public enum MouseEventFlags
{
    LEFTDOWN = 0x00000002,
    LEFTUP = 0x00000004,
    MIDDLEDOWN = 0x00000020,
    MIDDLEUP = 0x00000040,
    MOVE = 0x00000001,
    ABSOLUTE = 0x00008000,
    RIGHTDOWN = 0x00000008,
    RIGHTUP = 0x00000010,
    WHEEL = 0x00000800,
    XDOWN = 0x00000080,
    XUP = 0x00000100
}

3. 定义 MouseHookStruct 结构体：

[StructLayout(LayoutKind.Sequential)]
public struct MouseHookStruct
{
    public POINT pt;
    public int hwnd;
    public int wHitTestCode;
    public int dwExtraInfo;
}

4. 定义全局鼠标事件委托类型：

public delegate int HookProc(int nCode, IntPtr wParam, IntPtr lParam);

5. 定义全局变量和函数：

private static int hHook = 0;
private static HookProc HookProcedure;
[DllImport("user32.dll")]
public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);
[DllImport("user32.dll")]
public static extern int CallNextHookEx(int hHook, int nCode, IntPtr wParam, IntPtr lParam);
[DllImport("user32.dll")]
public static extern int UnhookWindowsHookEx(int hHook);

6. 实现钩子函数：

private static int MouseHookProc(int nCode, IntPtr wParam, IntPtr lParam)
{
    if (nCode >= 0)
    {
        MouseHookStruct mhs = (MouseHookStruct)Marshal.PtrToStructure(lParam, typeof(MouseHookStruct));
        if (wParam == (IntPtr)MouseEventFlags.LEFTDOWN)
        {
            MouseEventFlags button = MouseEventFlags.LEFTDOWN;
            MouseEventFlags swappedButton = MouseEventFlags.RIGHTDOWN;
            SwapMouseButton(button, swappedButton);
        }
        else if (wParam == (IntPtr)MouseEventFlags.RIGHTDOWN)
        {
            MouseEventFlags button = MouseEventFlags.RIGHTDOWN;
            MouseEventFlags swappedButton = MouseEventFlags.LEFTDOWN;
            SwapMouseButton(button, swappedButton);
        }
        else if (wParam == (IntPtr)MouseEventFlags.MOVE)
        {
            int x = mhs.pt.X;
            int y = mhs.pt.Y;
            SwapMouseMovement(ref x, ref y);
            mhs.pt.X = x;
            mhs.pt.Y = y;
            Marshal.StructureToPtr(mhs, lParam, true);
        }
    }
    return CallNextHookEx(hHook, nCode, wParam, lParam);
}

7. 实现鼠标按键互换和鼠标移动反向相反的方法：

private static void SwapMouseButton(MouseEventFlags button, MouseEventFlags swappedButton)
{
    int flags = GetSystemMetrics(0x0010);
    if ((flags & 0x0001) != 0)
    {
        // Primary mouse button is currently left button
        if ((button == MouseEventFlags.LEFTDOWN) || (button == MouseEventFlags.LEFTUP))
        {
            mouse_event((int)swappedButton, 0, 0, 0, 0);
        }
        else if ((button == MouseEventFlags.RIGHTDOWN) || (button == MouseEventFlags.RIGHTUP))
        {
            mouse_event((int)MouseEventFlags.LEFTDOWN, 0, 0, 0, 0);
            mouse_event((int)MouseEventFlags.LEFTUP, 0, 0, 0, 0);
        }
    }
    else
    {
        // Primary mouse button is currently right button
        if ((button == MouseEventFlags.RIGHTDOWN) || (button == MouseEventFlags.RIGHTUP))
        {
            mouse_event((int)swappedButton, 0, 0, 0, 0);
        }
        else if ((button == MouseEventFlags.LEFTDOWN) || (button == MouseEventFlags.LEFTUP))
        {
            mouse_event((int)MouseEventFlags.RIGHTDOWN, 0, 0, 0, 0);
            mouse_event((int)MouseEventFlags.RIGHTUP, 0, 0, 0, 0);
        }
    }
}

private static void SwapMouseMovement(ref int x, ref int y)
{
    int width = Screen.PrimaryScreen.Bounds.Width;
    int height = Screen.PrimaryScreen.Bounds.Height;
    x = width - x;
    y = height - y;
}

8. 注册全局钩子并启动：

HookProcedure = new HookProc(MouseHookProc);
hHook = SetWindowsHookEx(14, HookProcedure, Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly().GetModules()[0]), 0);

需要注意的是，这里使用了 user32.dll 中的一些函数，需要在代码中进行引用。同时，这里使用了 SetWindowsHookEx 函数注册了一个全局鼠标钩子，需要在程序关闭时调用 UnhookWindowsHookEx 函数取消注册。