C#2005中怎么用API中的SendInput

[Inpool]

[DllImport("user32.dll")]
public static extern unit SendInput(unit nInput,ref IInput[] pInputs int cbSize);

public interface IInput {}

public struct MouseInput : IInput {}

public struct KeyBoardInput : IInput {}

public struct HardWareInput : IInput {}

1、声明中的第二个参数这样写行不行
2、第三个参数要求提供输入INPUT结构的大小，但是VS.net 2005中sizeof关键字不允许以结构为参数，根据MSDN所说，Marshal.SizeOf返回的值是已封送处理类型后的值，测试证明用这个函数确实不行。
3、能不能在一个IInput数组中同时加入两种或以上的操作（例如一个鼠标移动、一个键盘按键按下和一个键盘弹起的操作序列），这个问题貌似还是如何取得结构大小的问题，不过更复杂点。

[Inpool]

自己顶

[li45214521]

Marshal.Sizoef(IInput）*pInputs.Length

[Inpool]

[Quote=引用 2 楼 li45214521 的回复:]
Marshal.Sizoef(IInput）*pInputs.Length
[/Quote]
能说详细点，Marshal.SizeOf的参数只能是变量
还有，pInputs没有Length属性，这个属性应该怎么定义呢？

[LQknife]

晓习 顶顶更健康

[ZengHD]

http://forums.microsoft.com/china/ShowPost.aspx?PostID=3597896&SiteID=15&pageid=0

        [DllImport("user32.dll")]
        public static extern UInt32 SendInput(UInt32 nInputs, ref INPUT pInputs, int cbSize);

        [StructLayout(LayoutKind.Explicit)]
        public struct INPUT
        {
            [FieldOffset(0)]
            public Int32 type;
            [FieldOffset(4)]
            public KEYBDINPUT ki;
            [FieldOffset(4)]
            public MOUSEINPUT mi;
            [FieldOffset(4)]
            public HARDWAREINPUT hi;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct MOUSEINPUT
        {
            public Int32 dx;
            public Int32 dy;
            public Int32 mouseData;
            public Int32 dwFlags;
            public Int32 time;
            public IntPtr dwExtraInfo;
        }
        [StructLayout(LayoutKind.Sequential)]
        public struct KEYBDINPUT
        {
            public Int16 wVk;
            public Int16 wScan;
            public Int32 dwFlags;
            public Int32 time;
            public IntPtr dwExtraInfo;
        }
        [StructLayout(LayoutKind.Sequential)]
        public struct HARDWAREINPUT
        {
            public Int32 uMsg;
            public Int16 wParamL;
            public Int16 wParamH;
        }
        
        public const int INPUT_KEYBOARD = 1;
        public const int KEYEVENTF_KEYUP = 0x0002;  

        private void button1_Click(object sender, EventArgs e)
        {
            INPUT inDown = new INPUT();

            inDown.type = INPUT_KEYBOARD;
            inDown.ki.wVk = (int)Keys.A;
            inDown.ki.dwFlags = KEYEVENTF_KEYUP;

            this.Text = SendInput(1, ref  inDown, Marshal.SizeOf(inDown)).ToString();

        }