（2）WH_MOUSE_LL Hook
WH_MOUSE_LL Hook監視輸入到線程消息隊列中的鼠標消息。
下面的 class 把 API 調用封裝起來以便調用。
1 // NativeMethods.cs
2 using system;
3 using system.Runtime.InteropServices;
4 using system.Drawing;
5
6 namespace CnBlogs.Youzai.ScreenKeyboard {
7 [StructLayout(LayoutKind.Sequential)]
8 internal struct MOUSEINPUT {
9 public int dx;
10 public int dy;
11 public int mouseData;
12 public int dwFlags;
13 public int time;
14 public IntPtr dwExtraInfo;
15 }
16
17 [StructLayout(LayoutKind.Sequential)]
18 internal struct KEYBDINPUT {
19 public short wVk;
20 public short wScan;
21 public int dwFlags;
22 public int time;
23 public IntPtr dwExtraInfo;
24 }
25
26 [StructLayout(LayoutKind.Explicit)]
27 internal struct Input {
28 [FIEldOffset(0)]
29 public int type;
30 [FIEldOffset(4)]
31 public MOUSEINPUT mi;
32 [FIEldOffset(4)]
33 public KEYBDINPUT ki;
34 [FIEldOffset(4)]
35 public HARDWAREINPUT hi;
36 }
37
38 [StructLayout(LayoutKind.Sequential)]
39 internal struct HARDWAREINPUT {
40 public int uMsg;
41 public short wParamL;
42 public short wParamH;
43 }
44
45 internal class INPUT {
46 public const int MOUSE = 0;
47 public const int KEYBOARD = 1;
48 public const int HARDWARE = 2;
49 }
50
51 internal static class NativeMethods {
52 [DllImport("User32.dll", CharSet = CharSet.Auto, SetLastError = false)]
53 internal static extern IntPtr GetWindowLong(IntPtr hWnd, int nIndex);
54
55 [DllImport("User32.dll", CharSet = CharSet.Auto, SetLastError = false)]
56 internal static extern IntPtr SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
57
58 [DllImport("User32.dll", EntryPoint = "SendInput", CharSet = CharSet.Auto)]
59 internal static extern UInt32 SendInput(UInt32 nInputs, Input[] pInputs, Int32 cbSize);
60
61 [DllImport("Kernel32.dll", EntryPoint = "GetTickCount", CharSet = CharSet.Auto)]
62 internal static extern int GetTickCount();
63
64 [DllImport("User32.dll", EntryPoint = "GetKeyState", CharSet = CharSet.Auto)]
65 internal static extern short GetKeyState(int nVirtKey);
66
67 [DllImport("User32.dll", EntryPoint = "SendMessage", CharSet = CharSet.Auto)]
68 internal static extern IntPtr SendMessage(IntPtr hWnd, int msg, IntPtr wParam,
IntPtr lParam);
69 }
70}
