SendInput 和 64 位

下面是我用来通过 SendInput API 模拟按键的一些代码的摘录。如果我将应用程序设置为针对 x86 CPU 编译，则此方法可以正常工作，但不适用于 x64 CPU 编译。

我猜这与 x64 使用双倍大小指针有关，但我试图改变这一点[FieldOffset(4)]对此[FieldOffset(8)]但没有成功。

是否与导入 32 位版本的 user32.dll 有关？

    #region SendInput API

    [DllImport("user32.dll", EntryPoint = "SendInput", SetLastError = true)]
    static extern uint SendInput(uint nInputs, INPUT[] pInputs, int cbSize);

    [DllImport("user32.dll", EntryPoint = "GetMessageExtraInfo", SetLastError = true)]
    static extern IntPtr GetMessageExtraInfo();

    private enum KeyEvent
    {
        KeyUp = 0x0002,
        KeyDown = 0x0000,
        ExtendedKey = 0x0001
    }

    private struct KEYBDINPUT
    {
        public ushort wVk;
        public ushort wScan;
        public uint dwFlags;
        public long time;
        public uint dwExtraInfo;
    };

    [StructLayout(LayoutKind.Explicit, Size = 28)]
    private struct INPUT
    {
        [FieldOffset(0)]
        public uint type;
        [FieldOffset(4)]
        public KEYBDINPUT ki;
    };

    #endregion

    public void sendKey(KeyCode Key)
    {
        INPUT[] InputList = new INPUT[2];

        INPUT keyInput = new INPUT();
        keyInput.type = 1;

        keyInput.ki.wScan = 0;
        keyInput.ki.time = 0;
        keyInput.ki.dwFlags = (int)KeyEvent.KeyDown;
        keyInput.ki.dwExtraInfo = (uint)GetMessageExtraInfo();
        keyInput.ki.wVk = (ushort)Key;

        InputList[0] = keyInput;

        keyInput.ki.dwFlags = (int)KeyEvent.KeyUp;

        InputList[1] = keyInput;

        SendInput((uint)2, InputList, Marshal.SizeOf(InputList[0]));
    }

除了 SLAks 发现的错误之外，剩下的问题是INPUT是不正确的。这意味着SendInput失败，因为它接收到类型的参数INPUT[]。您不能指定尺寸StructLayout(LayoutKind.Explicit, Size = 28)因为您需要处理 x86 和 x64 的代码。

这一切都源于这样一个事实：您只包含了KEYBRDINPUT结构体INPUT. The MOUSEINPUT结构体大于KEYBRDINPUT这就是你的问题的原因。

最好的解决方案是正确定义 INPUT 结构，包括 union 部分。这样做（声明取自pinvoke.net).

[StructLayout(LayoutKind.Sequential)]
struct MOUSEINPUT
{
    public int dx;
    public int dy;
    public uint mouseData;
    public uint dwFlags;
    public uint time;
    public IntPtr dwExtraInfo;
}

[StructLayout(LayoutKind.Sequential)]
struct KEYBDINPUT 
{
     public ushort wVk;
     public ushort wScan;
     public uint dwFlags;
     public uint time;
     public IntPtr dwExtraInfo;
}

[StructLayout(LayoutKind.Sequential)]
struct HARDWAREINPUT
{
     public int uMsg;
     public short wParamL;
     public short wParamH;
}

[StructLayout(LayoutKind.Explicit)]
struct MouseKeybdHardwareInputUnion
{
    [FieldOffset(0)]
    public MOUSEINPUT mi;

    [FieldOffset(0)]
    public KEYBDINPUT ki;

    [FieldOffset(0)]
    public HARDWAREINPUT hi;
}

[StructLayout(LayoutKind.Sequential)]
struct INPUT
{
    public uint type;
    public MouseKeybdHardwareInputUnion mkhi;
}