public class KeyBoardHookStruct {
public int vkCode; public int scanCode; public int flags; public int time; public int dwExtraInfo; }
#region DllImport //设置钩子
[DllImport("user32.dll",
CharSet
=
CharSet.Auto,
CallingConvention = CallingConvention.StdCall)]
public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId); [DllImport("user32.dll",
CharSet
=
CharSet.Auto,
CallingConvention = CallingConvention.StdCall)] //抽掉钩子
public static extern bool UnhookWindowsHookEx(int idHook); [DllImport("user32.dll",
CharSet
=
CharSet.Auto,
CallingConvention = CallingConvention.StdCall)] //调用下一个钩子
public static extern int CallNextHookEx(int idHook, int nCode, IntPtr
wParam, IntPtr lParam); //取得模块句柄
[DllImport("kernel32.dll",
CharSet
=
CharSet.Auto,
CallingConvention = CallingConvention.StdCall)]
private static extern IntPtr GetModuleHandle(string lpModuleName);
//寻找目标进程窗口
[DllImport("USER32.DLL")]
public static extern IntPtr FindWindow(string lpClassName, string lpWindowName); //设置进程窗口到最前
[DllImport("USER32.DLL")]
public static extern bool SetForegroundWindow(IntPtr hWnd); //模拟键盘事件
[DllImport("User32.dll")]
public static extern void keybd_event(Byte bVk, Byte bScan, Int32 dwFlags, Int32 dwExtraInfo);
//释放按键的常量
private const int KEYEVENTF_KEYUP =2;
本例所使用
的函数比较少，它们都在系统的USER32.dll里，包括：设置和取消钩子、调用下一个钩子、导入进程、模拟键盘等等。我们依次导入它们。
这些函数的命名规范合理，几乎只根据函数名就能知道其功能。
如果读者对于其中的某些函数不熟悉，请自行搜索MSDN。 二、使用Windows API设置钩子
有了以上windows API函数的声明，下一步就是设置钩子了。
寥寥两行代码，但包含了相当丰富的内容。 C#代码 1.//委托
2.public delegate int HookProc(int nCode, IntPtr wParam, IntPtr lParam);
3. 4. 5.
6.public void Hook_Start() 7. {
8. // 安装键盘钩子 9. if (hHook == 0) 10. {
11. KeyBoardHookProcedure = new HookProc(KeyBoardHookProc); 12.
13. hHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyBoardHookProcedure,
GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0);
14. 15. } 16. } //委托
public delegate int HookProc(int nCode, IntPtr wParam, IntPtr lParam);
public void Hook_Start() {
// 安装键盘钩子 if (hHook == 0) {
KeyBoardHookProcedure = new HookProc(KeyBoardHookProc); hHook
=
SetWindowsHookEx(WH_KEYBOARD_LL,
KeyBoardHookProcedure,
GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0); } }
先介绍一下设置钩子的明星函数：SetWindowsHookEx 。它的参数说明如下。SetWindowsHookEx( idHook: Integer; {钩子类型} lpfn: TFNHookProc; {函数指针}
hmod: HINST; {包含钩子函数的模块(EXE、DLL)句柄; 一般是 HInstance; 如果是当前线程这里可以是 0}
dwThreadId: DWORD {关联的线程; 可用 GetCurrentThreadId 获取