全局鼠标键盘事件实现应用程序的自动锁定
2014-08-15 11:54
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我们在进行信息系统开发的时候，有时为了系统数据保密性、安全性得到提升。需要考虑到如果在用户长时间内没有对鼠标及键盘进行操作时，让应用程序自动锁定。并将当前用户所操作的界面隐藏。那么，为了实现该功能，我们需要对整个计算机内部的鼠标及键盘的操作进行记录。如果长时间内记录没有发生变化，则可以对系统进行锁定。
一、关键类的实现
在.NET现有的类库中，并没有实现对全局（可能是我没有发现）鼠标、键盘操作的相关事件及类的定义。为此，我们需要调用到API来辅助我们这个功能的实现。
那么，我们现在来定义一个API相关的类。并对鼠标、键盘的Hook进行定义及处理。现对这个类暂命名为：MouseKeyHook。
下面是MouseKeyHook的代码：
public class MouseKeyHook
{
[StructLayout(LayoutKind.Sequential)]
private class POINT
{
public int x;
public int y;
}
[StructLayout(LayoutKind.Sequential)]
private class MouseHookStruct
{
public POINT pt;
public int hwnd;
public int wHitTestCode;
public int dwExtraInfo;
}
[StructLayout(LayoutKind.Sequential)]
private class MouseLLHookStruct
{
public POINT pt;
public int mouseData;
public int flags;
public int time;
public int dwExtraInfo;
}
[StructLayout(LayoutKind.Sequential)]
private class KeyboardHookStruct
{
public int vkCode;
public int scanCode;
public int flags;
public int time;
public int dwExtraInfo;
}
[DllImport("user32.dll", CharSet = CharSet.Auto,
CallingConvention = CallingConvention.StdCall, SetLastError = true)]
private static extern int SetWindowsHookEx(
int idHook,
HookProc lpfn,
IntPtr hMod,
int dwThreadId);
[DllImport("user32.dll", CharSet = CharSet.Auto,
CallingConvention = CallingConvention.StdCall, SetLastError = true)]
private static extern int UnhookWindowsHookEx(int idHook);
[DllImport("user32.dll", CharSet = CharSet.Auto,
CallingConvention = CallingConvention.StdCall)]
private static extern int CallNextHookEx(
int idHook,
int nCode,
int wParam,
IntPtr lParam);
private delegate int HookProc(int nCode, int wParam, IntPtr lParam);
[DllImport("user32")]
private static extern int ToAscii(
int uVirtKey,
int uScanCode,
byte[] lpbKeyState,
byte[] lpwTransKey,
int fuState);
[DllImport("user32")]
private static extern int GetKeyboardState(byte[] pbKeyState);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
private static extern short GetKeyState(int vKey);
private const int WH_MOUSE_LL = 14;
private const int WH_KEYBOARD_LL = 13;
private const int WH_MOUSE = 7;
private const int WH_KEYBOARD = 2;
private const int WM_MOUSEMOVE = 0x200;
private const int WM_LBUTTONDOWN = 0x201;
private const int WM_RBUTTONDOWN = 0x204;
private const int WM_MBUTTONDOWN = 0x207;
private const int WM_LBUTTONUP = 0x202;
private const int WM_RBUTTONUP = 0x205;
private const int WM_MBUTTONUP = 0x208;
private const int WM_LBUTTONDBLCLK = 0x203;
private const int WM_RBUTTONDBLCLK = 0x206;
private const int WM_MBUTTONDBLCLK = 0x209;
private const int WM_MOUSEWHEEL = 0x020A;
private const int WM_KEYDOWN = 0x100;
private const int WM_KEYUP = 0x101;
private const int WM_SYSKEYDOWN = 0x104;
private const int WM_SYSKEYUP = 0x105;
private const byte VK_SHIFT = 0x10;
private const byte VK_CAPITAL = 0x14;
private const byte VK_NUMLOCK = 0x90;
public MouseKeyHook()
{
Start();
}
public MouseKeyHook(bool InstallMouseHook, bool InstallKeyboardHook)
{
Start(InstallMouseHook, InstallKeyboardHook);
}
~MouseKeyHook()
{
Stop(true, true, false);
}
public event MouseEventHandler OnMouseActivity;
public event KeyEventHandler KeyDown;
public event KeyPressEventHandler KeyPress;
public event KeyEventHandler KeyUp;
private int hMouseHook = 0;
private int hKeyboardHook = 0;
private static HookProc MouseHookProcedure;
private static HookProc KeyboardHookProcedure;
public void Start()
{
this.Start(true, true);
}
public void Start(bool InstallMouseHook, bool InstallKeyboardHook)
{
if (hMouseHook == 0 && InstallMouseHook)
{
MouseHookProcedure = new HookProc(MouseHookProc);
hMouseHook = SetWindowsHookEx(
WH_MOUSE_LL,
MouseHookProcedure,
Marshal.GetHINSTANCE(
Assembly.GetExecutingAssembly().GetModules()[0]),
0);
if (hMouseHook == 0)
{
int errorCode = Marshal.GetLastWin32Error();
Stop(true, false, false);
throw new Win32Exception(errorCode);
}
}
if (hKeyboardHook == 0 && InstallKeyboardHook)
{
KeyboardHookProcedure = new HookProc(KeyboardHookProc);
hKeyboardHook = SetWindowsHookEx(
WH_KEYBOARD_LL,
KeyboardHookProcedure,
Marshal.GetHINSTANCE(
Assembly.GetExecutingAssembly().GetModules()[0]),
0);
if (hKeyboardHook == 0)
{
int errorCode = Marshal.GetLastWin32Error();
Stop(false, true, false);
throw new Win32Exception(errorCode);
}
}
}
public void Stop()
{
this.Stop(true, true, true);
}
public void Stop(bool UninstallMouseHook, bool UninstallKeyboardHook, bool ThrowExceptions)
{
if (hMouseHook != 0 && UninstallMouseHook)
{
int retMouse = UnhookWindowsHookEx(hMouseHook);
hMouseHook = 0;
if (retMouse == 0 && ThrowExceptions)
{
int errorCode = Marshal.GetLastWin32Error();
throw new Win32Exception(errorCode);
}
}
if (hKeyboardHook != 0 && UninstallKeyboardHook)
{
int retKeyboard = UnhookWindowsHookEx(hKeyboardHook);
hKeyboardHook = 0;
if (retKeyboard == 0 && ThrowExceptions)
{
int errorCode = Marshal.GetLastWin32Error();
throw new Win32Exception(errorCode);
}
}
}
private int MouseHookProc(int nCode, int wParam, IntPtr lParam)
{
if ((nCode >= 0) && (OnMouseActivity != null))
{
MouseLLHookStruct mouseHookStruct = (MouseLLHookStruct)Marshal.PtrToStructure(lParam, typeof(MouseLLHookStruct));
MouseButtons button = MouseButtons.None;
short mouseDelta = 0;
switch (wParam)
{
case WM_LBUTTONDOWN:
button = MouseButtons.Left;
break;
case WM_RBUTTONDOWN:
button = MouseButtons.Right;
break;
case WM_MOUSEWHEEL:
mouseDelta = (short)((mouseHookStruct.mouseData >> 16) & 0xffff);
break;
}
int clickCount = 0;
if (button != MouseButtons.None)
if (wParam == WM_LBUTTONDBLCLK || wParam == WM_RBUTTONDBLCLK) clickCount = 2;
else clickCount = 1;
MouseEventArgs e = new MouseEventArgs(
button,
clickCount,
mouseHookStruct.pt.x,
mouseHookStruct.pt.y,
mouseDelta);
OnMouseActivity(this, e);
}
return CallNextHookEx(hMouseHook, nCode, wParam, lParam);
}
private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
{
bool handled = false;
if ((nCode >= 0) && (KeyDown != null || KeyUp != null || KeyPress != null))
{
KeyboardHookStruct MyKeyboardHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));
if (KeyDown != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN))
{
Keys keyData = (Keys)MyKeyboardHookStruct.vkCode;
KeyEventArgs e = new KeyEventArgs(keyData);
KeyDown(this, e);
handled = handled || e.Handled;
}
if (KeyPress != null && wParam == WM_KEYDOWN)
{
bool isDownShift = ((GetKeyState(VK_SHIFT) & 0x80) == 0x80 ? true : false);
bool isDownCapslock = (GetKeyState(VK_CAPITAL) != 0 ? true : false);
byte[] keyState = new byte[256];
GetKeyboardState(keyState);
byte[] inBuffer = new byte[2];
if (ToAscii(MyKeyboardHookStruct.vkCode,
MyKeyboardHookStruct.scanCode,
keyState,
inBuffer,
MyKeyboardHookStruct.flags) == 1)
{
char key = (char)inBuffer[0];
if ((isDownCapslock ^ isDownShift) && Char.IsLetter(key)) key = Char.ToUpper(key);
KeyPressEventArgs e = new KeyPressEventArgs(key);
KeyPress(this, e);
handled = handled || e.Handled;
}
}
if (KeyUp != null && (wParam == WM_KEYUP || wParam == WM_SYSKEYUP))
{
Keys keyData = (Keys)MyKeyboardHookStruct.vkCode;
KeyEventArgs e = new KeyEventArgs(keyData);
KeyUp(this, e);
handled = handled || e.Handled;
}
}
if (handled)
return 1;
else
return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);
}
}
通过上述类，我们可以来实现我们的应用程序的自动锁定功能了。
二、建测试项目
1、新建一个Windows应用程序。命名为：WindowsApplication1。
2、在该应用程序内添加一个类。类名为MouseKeyHook.cs，将上述代码添复制到该类中。
3、在Form1中添加一个Timer控件。
4、单击F7键打开Form1.cs。在里面添加局部变量：
private MouseKeyHook mouseKeyHook1=new MouseKeyHook(true,true);
5、在Form1的构造函数中添加如下代码：
public Form1()
{
InitializeComponent();
timer1.Interval=60000;//该处是定义一分钟的时间
mouseKeyHook1.KeyDown+=new KeyEventHandler(mouseKeyHook1_KeyDown);
mouseKeyHook1.KeyPress+=new KeyPressEventHandler(mouseKeyHook1_KeyPress);
mouseKeyHook1.KeyUp+=new KeyEventHandler(mouseKeyHook1_KeyUp);
mouseKeyHook1.OnMouseActivity+=new MouseEventHandler(mouseKeyHook1_OnMouseActivity);
mouseKeyHook1.Start(true,true);
}
6、打开Form1的设计窗口，在窗口内双击timer1，定义timer1的Tick事件。在Tick事件中加载如下代码：
private void timer_Tick(object sender, EventArgs e)
{
MessageBox.Show("该应用程序将被锁定。","提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
Process.Start("logon.scr");//在这里启动一个屏幕保护程序。
}
7、定义mouseKeyHook1_KeyDown、mouseKeyHook1_KeyPress、mouseKeyHook1_KeyUp、mouseKeyHook1_OnMouseActivity事件。这几个事件调用的事件是一样的。即启动计时器。实现应用程序定时锁定的功能。下面举一例：
private mouseKeyHook1_KeyDown(object sender, KeyEventArgs e)
{
TimerClear();
}
//重新设置计时器
private void TimerClear()
{
timer1.Stop();
timer1.Start();
}
8、保存所有文件后，按“F5”键启动应用程序。
一、关键类的实现
在.NET现有的类库中，并没有实现对全局（可能是我没有发现）鼠标、键盘操作的相关事件及类的定义。为此，我们需要调用到API来辅助我们这个功能的实现。
那么，我们现在来定义一个API相关的类。并对鼠标、键盘的Hook进行定义及处理。现对这个类暂命名为：MouseKeyHook。
下面是MouseKeyHook的代码：
public class MouseKeyHook
{
[StructLayout(LayoutKind.Sequential)]
private class POINT
{
public int x;
public int y;
}
[StructLayout(LayoutKind.Sequential)]
private class MouseHookStruct
{
public POINT pt;
public int hwnd;
public int wHitTestCode;
public int dwExtraInfo;
}
[StructLayout(LayoutKind.Sequential)]
private class MouseLLHookStruct
{
public POINT pt;
public int mouseData;
public int flags;
public int time;
public int dwExtraInfo;
}
[StructLayout(LayoutKind.Sequential)]
private class KeyboardHookStruct
{
public int vkCode;
public int scanCode;
public int flags;
public int time;
public int dwExtraInfo;
}
[DllImport("user32.dll", CharSet = CharSet.Auto,
CallingConvention = CallingConvention.StdCall, SetLastError = true)]
private static extern int SetWindowsHookEx(
int idHook,
HookProc lpfn,
IntPtr hMod,
int dwThreadId);
[DllImport("user32.dll", CharSet = CharSet.Auto,
CallingConvention = CallingConvention.StdCall, SetLastError = true)]
private static extern int UnhookWindowsHookEx(int idHook);
[DllImport("user32.dll", CharSet = CharSet.Auto,
CallingConvention = CallingConvention.StdCall)]
private static extern int CallNextHookEx(
int idHook,
int nCode,
int wParam,
IntPtr lParam);
private delegate int HookProc(int nCode, int wParam, IntPtr lParam);
[DllImport("user32")]
private static extern int ToAscii(
int uVirtKey,
int uScanCode,
byte[] lpbKeyState,
byte[] lpwTransKey,
int fuState);
[DllImport("user32")]
private static extern int GetKeyboardState(byte[] pbKeyState);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
private static extern short GetKeyState(int vKey);
private const int WH_MOUSE_LL = 14;
private const int WH_KEYBOARD_LL = 13;
private const int WH_MOUSE = 7;
private const int WH_KEYBOARD = 2;
private const int WM_MOUSEMOVE = 0x200;
private const int WM_LBUTTONDOWN = 0x201;
private const int WM_RBUTTONDOWN = 0x204;
private const int WM_MBUTTONDOWN = 0x207;
private const int WM_LBUTTONUP = 0x202;
private const int WM_RBUTTONUP = 0x205;
private const int WM_MBUTTONUP = 0x208;
private const int WM_LBUTTONDBLCLK = 0x203;
private const int WM_RBUTTONDBLCLK = 0x206;
private const int WM_MBUTTONDBLCLK = 0x209;
private const int WM_MOUSEWHEEL = 0x020A;
private const int WM_KEYDOWN = 0x100;
private const int WM_KEYUP = 0x101;
private const int WM_SYSKEYDOWN = 0x104;
private const int WM_SYSKEYUP = 0x105;
private const byte VK_SHIFT = 0x10;
private const byte VK_CAPITAL = 0x14;
private const byte VK_NUMLOCK = 0x90;
public MouseKeyHook()
{
Start();
}
public MouseKeyHook(bool InstallMouseHook, bool InstallKeyboardHook)
{
Start(InstallMouseHook, InstallKeyboardHook);
}
~MouseKeyHook()
{
Stop(true, true, false);
}
public event MouseEventHandler OnMouseActivity;
public event KeyEventHandler KeyDown;
public event KeyPressEventHandler KeyPress;
public event KeyEventHandler KeyUp;
private int hMouseHook = 0;
private int hKeyboardHook = 0;
private static HookProc MouseHookProcedure;
private static HookProc KeyboardHookProcedure;
public void Start()
{
this.Start(true, true);
}
public void Start(bool InstallMouseHook, bool InstallKeyboardHook)
{
if (hMouseHook == 0 && InstallMouseHook)
{
MouseHookProcedure = new HookProc(MouseHookProc);
hMouseHook = SetWindowsHookEx(
WH_MOUSE_LL,
MouseHookProcedure,
Marshal.GetHINSTANCE(
Assembly.GetExecutingAssembly().GetModules()[0]),
0);
if (hMouseHook == 0)
{
int errorCode = Marshal.GetLastWin32Error();
Stop(true, false, false);
throw new Win32Exception(errorCode);
}
}
if (hKeyboardHook == 0 && InstallKeyboardHook)
{
KeyboardHookProcedure = new HookProc(KeyboardHookProc);
hKeyboardHook = SetWindowsHookEx(
WH_KEYBOARD_LL,
KeyboardHookProcedure,
Marshal.GetHINSTANCE(
Assembly.GetExecutingAssembly().GetModules()[0]),
0);
if (hKeyboardHook == 0)
{
int errorCode = Marshal.GetLastWin32Error();
Stop(false, true, false);
throw new Win32Exception(errorCode);
}
}
}
public void Stop()
{
this.Stop(true, true, true);
}
public void Stop(bool UninstallMouseHook, bool UninstallKeyboardHook, bool ThrowExceptions)
{
if (hMouseHook != 0 && UninstallMouseHook)
{
int retMouse = UnhookWindowsHookEx(hMouseHook);
hMouseHook = 0;
if (retMouse == 0 && ThrowExceptions)
{
int errorCode = Marshal.GetLastWin32Error();
throw new Win32Exception(errorCode);
}
}
if (hKeyboardHook != 0 && UninstallKeyboardHook)
{
int retKeyboard = UnhookWindowsHookEx(hKeyboardHook);
hKeyboardHook = 0;
if (retKeyboard == 0 && ThrowExceptions)
{
int errorCode = Marshal.GetLastWin32Error();
throw new Win32Exception(errorCode);
}
}
}
private int MouseHookProc(int nCode, int wParam, IntPtr lParam)
{
if ((nCode >= 0) && (OnMouseActivity != null))
{
MouseLLHookStruct mouseHookStruct = (MouseLLHookStruct)Marshal.PtrToStructure(lParam, typeof(MouseLLHookStruct));
MouseButtons button = MouseButtons.None;
short mouseDelta = 0;
switch (wParam)
{
case WM_LBUTTONDOWN:
button = MouseButtons.Left;
break;
case WM_RBUTTONDOWN:
button = MouseButtons.Right;
break;
case WM_MOUSEWHEEL:
mouseDelta = (short)((mouseHookStruct.mouseData >> 16) & 0xffff);
break;
}
int clickCount = 0;
if (button != MouseButtons.None)
if (wParam == WM_LBUTTONDBLCLK || wParam == WM_RBUTTONDBLCLK) clickCount = 2;
else clickCount = 1;
MouseEventArgs e = new MouseEventArgs(
button,
clickCount,
mouseHookStruct.pt.x,
mouseHookStruct.pt.y,
mouseDelta);
OnMouseActivity(this, e);
}
return CallNextHookEx(hMouseHook, nCode, wParam, lParam);
}
private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
{
bool handled = false;
if ((nCode >= 0) && (KeyDown != null || KeyUp != null || KeyPress != null))
{
KeyboardHookStruct MyKeyboardHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));
if (KeyDown != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN))
{
Keys keyData = (Keys)MyKeyboardHookStruct.vkCode;
KeyEventArgs e = new KeyEventArgs(keyData);
KeyDown(this, e);
handled = handled || e.Handled;
}
if (KeyPress != null && wParam == WM_KEYDOWN)
{
bool isDownShift = ((GetKeyState(VK_SHIFT) & 0x80) == 0x80 ? true : false);
bool isDownCapslock = (GetKeyState(VK_CAPITAL) != 0 ? true : false);
byte[] keyState = new byte[256];
GetKeyboardState(keyState);
byte[] inBuffer = new byte[2];
if (ToAscii(MyKeyboardHookStruct.vkCode,
MyKeyboardHookStruct.scanCode,
keyState,
inBuffer,
MyKeyboardHookStruct.flags) == 1)
{
char key = (char)inBuffer[0];
if ((isDownCapslock ^ isDownShift) && Char.IsLetter(key)) key = Char.ToUpper(key);
KeyPressEventArgs e = new KeyPressEventArgs(key);
KeyPress(this, e);
handled = handled || e.Handled;
}
}
if (KeyUp != null && (wParam == WM_KEYUP || wParam == WM_SYSKEYUP))
{
Keys keyData = (Keys)MyKeyboardHookStruct.vkCode;
KeyEventArgs e = new KeyEventArgs(keyData);
KeyUp(this, e);
handled = handled || e.Handled;
}
}
if (handled)
return 1;
else
return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);
}
}
通过上述类，我们可以来实现我们的应用程序的自动锁定功能了。
二、建测试项目
1、新建一个Windows应用程序。命名为：WindowsApplication1。
2、在该应用程序内添加一个类。类名为MouseKeyHook.cs，将上述代码添复制到该类中。
3、在Form1中添加一个Timer控件。
4、单击F7键打开Form1.cs。在里面添加局部变量：
private MouseKeyHook mouseKeyHook1=new MouseKeyHook(true,true);
5、在Form1的构造函数中添加如下代码：
public Form1()
{
InitializeComponent();
timer1.Interval=60000;//该处是定义一分钟的时间
mouseKeyHook1.KeyDown+=new KeyEventHandler(mouseKeyHook1_KeyDown);
mouseKeyHook1.KeyPress+=new KeyPressEventHandler(mouseKeyHook1_KeyPress);
mouseKeyHook1.KeyUp+=new KeyEventHandler(mouseKeyHook1_KeyUp);
mouseKeyHook1.OnMouseActivity+=new MouseEventHandler(mouseKeyHook1_OnMouseActivity);
mouseKeyHook1.Start(true,true);
}
6、打开Form1的设计窗口，在窗口内双击timer1，定义timer1的Tick事件。在Tick事件中加载如下代码：
private void timer_Tick(object sender, EventArgs e)
{
MessageBox.Show("该应用程序将被锁定。","提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
Process.Start("logon.scr");//在这里启动一个屏幕保护程序。
}
7、定义mouseKeyHook1_KeyDown、mouseKeyHook1_KeyPress、mouseKeyHook1_KeyUp、mouseKeyHook1_OnMouseActivity事件。这几个事件调用的事件是一样的。即启动计时器。实现应用程序定时锁定的功能。下面举一例：
private mouseKeyHook1_KeyDown(object sender, KeyEventArgs e)
{
TimerClear();
}
//重新设置计时器
private void TimerClear()
{
timer1.Stop();
timer1.Start();
}
8、保存所有文件后，按“F5”键启动应用程序。
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