主题：请教一下这段如何在全局中使用

Imports System.Reflection, System.Threading, System.ComponentModel, System.Runtime.InteropServices

Public Class hook

#Region "定义结构"

Private Structure MouseHookStruct

Dim PT As Point

Dim Hwnd As Integer

Dim WHitTestCode As Integer

Dim DwExtraInfo As Integer

End Structure

Private Structure MouseLLHookStruct

Dim PT As Point

Dim MouseData As Integer

Dim Flags As Integer

Dim Time As Integer

Dim DwExtraInfo As Integer

End Structure

Private Structure KeyboardHookStruct

Dim vkCode As Integer

Dim ScanCode As Integer

Dim Flags As Integer

Dim Time As Integer

Dim DwExtraInfo As Integer

End Structure

#End Region

#Region "API声明导入"

Private Declare Function SetWindowsHookExA Lib "user32" (ByVal idHook As Integer, ByVal lpfn As HookProc, ByVal hMod As IntPtr, ByVal dwThreadId As Integer) As Integer

Private Declare Function UnhookWindowsHookEx Lib "user32" (ByVal idHook As Integer) As Integer

Private Declare Function CallNextHookEx Lib "user32" (ByVal idHook As Integer, ByVal nCode As Integer, ByVal wParam As Integer, ByVal lParam As IntPtr) As Integer

Private Declare Function ToAscii Lib "user32" (ByVal uVirtKey As Integer, ByVal uScancode As Integer, ByVal lpdKeyState As Byte(), ByVal lpwTransKey As Byte(), ByVal fuState As Integer) As Integer

Private Declare Function GetKeyboardState Lib "user32" (ByVal pbKeyState As Byte()) As Integer

Private Declare Function GetKeyState Lib "user32" (ByVal vKey As Integer) As Short

Private Delegate Function HookProc(ByVal nCode As Integer, ByVal wParam As Integer, ByVal lParam As IntPtr) As Integer

#End Region

#Region "常量声明"

Private Const WH_MOUSE_LL = 14

Private Const WH_KEYBOARD_LL = 13

Private Const WH_MOUSE = 7

Private Const WH_KEYBOARD = 2

Private Const WM_MOUSEMOVE = &H200

Private Const WM_LBUTTONDOWN = &H201

Private Const WM_RBUTTONDOWN = &H204

Private Const WM_MBUTTONDOWN = &H207

Private Const WM_LBUTTONUP = &H202

Private Const WM_RBUTTONUP = &H205

Private Const WM_MBUTTONUP = &H208

Private Const WM_LBUTTONDBLCLK = &H203

Private Const WM_RBUTTONDBLCLK = &H206

Private Const WM_MBUTTONDBLCLK = &H209

Private Const WM_MOUSEWHEEL = &H20A

Private Const WM_KEYDOWN = &H100

Private Const WM_KEYUP = &H101

Private Const WM_SYSKEYDOWN = &H104

Private Const WM_SYSKEYUP = &H105

Private Const VK_SHIFT As Byte = &H10

Private Const VK_CAPITAL As Byte = &H14

Private Const VK_NUMLOCK As Byte = &H90

#End Region

''' <summary>鼠标激活事件</summary>

Public Event MouseActivity As MouseEventHandler

''' <summary>键盘按下事件</summary>

Public Event KeyDown As KeyEventHandler

''' <summary>键盘输入事件</summary>

Public Event KeyPress As KeyPressEventHandler

''' <summary>键盘松开事件</summary>

Public Event KeyUp As KeyEventHandler

Private hMouseHook As Integer

Private hKeyboardHook As Integer

Private Shared MouseHookProcedure As HookProc

Private Shared KeyboardHookProcedure As HookProc

''' <summary>创建一个全局鼠标键盘钩子 (请使用Start方法开始监视)</summary>

Sub New()

'留空即可

End Sub

''' <summary>创建一个全局鼠标键盘钩子，决定是否安装钩子</summary>

''' <param name="InstallAll">是否立刻挂钩系统消息</param>

Sub New(ByVal InstallAll As Boolean)

If InstallAll Then StartHook(True, True)

End Sub

''' <summary>创建一个全局鼠标键盘钩子，并决定安装钩子的类型</summary>

''' <param name="InstallKeyboard">挂钩键盘消息</param>

''' <param name="InstallMouse">挂钩鼠标消息</param>

Sub New(ByVal InstallKeyboard As Boolean, ByVal InstallMouse As Boolean)

StartHook(InstallKeyboard, InstallMouse)

End Sub

''' <summary>析构函数</summary>

Protected Overrides Sub Finalize()

UnHook() '卸载对象时反注册系统钩子

MyBase.Finalize()

End Sub

''' <summary>开始安装系统钩子</summary>

''' <param name="InstallKeyboardHook">挂钩键盘消息</param>

''' <param name="InstallMouseHook">挂钩鼠标消息</param>

Public Sub StartHook(Optional ByVal InstallKeyboardHook As Boolean = True, Optional ByVal InstallMouseHook As Boolean = False)

'注册键盘钩子

If InstallKeyboardHook AndAlso hKeyboardHook = 0 Then

KeyboardHookProcedure = New HookProc(AddressOf KeyboardHookProc)

hKeyboardHook = SetWindowsHookExA(WH_KEYBOARD_LL, KeyboardHookProcedure, Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly.GetModules()(0)), 0)

If hKeyboardHook = 0 Then '检测是否注册完成

UnHook(True, False) '在这里反注册

Throw New Win32Exception(Marshal.GetLastWin32Error) '报告错误

End If

End If

'注册鼠标钩子

If InstallMouseHook AndAlso hMouseHook = 0 Then

MouseHookProcedure = New HookProc(AddressOf MouseHookProc)

hMouseHook = SetWindowsHookExA(WH_MOUSE_LL, MouseHookProcedure, Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly.GetModules()(0)), 0)

If hMouseHook = 0 Then

UnHook(False, True)

Throw New Win32Exception(Marshal.GetLastWin32Error)

End If

End If

End Sub

''' <summary>立刻卸载系统钩子</summary>

''' <param name="UninstallKeyboardHook">卸载键盘钩子</param>

''' <param name="UninstallMouseHook">卸载鼠标钩子</param>

''' <param name="ThrowExceptions">是否报告错误</param>

Public Sub UnHook(Optional ByVal UninstallKeyboardHook As Boolean = True, Optional ByVal UninstallMouseHook As Boolean = True, Optional ByVal ThrowExceptions As Boolean = False)

'卸载键盘钩子

If hKeyboardHook <> 0 AndAlso UninstallKeyboardHook Then

Dim retKeyboard As Integer = UnhookWindowsHookEx(hKeyboardHook)

hKeyboardHook = 0

If ThrowExceptions AndAlso retKeyboard = 0 Then '如果出现错误，是否报告错误

Throw New Win32Exception(Marshal.GetLastWin32Error) '报告错误

End If

End If

'卸载鼠标钩子

If hMouseHook <> 0 AndAlso UninstallMouseHook Then

Dim retMouse As Integer = UnhookWindowsHookEx(hMouseHook)

hMouseHook = 0

If ThrowExceptions AndAlso retMouse = 0 Then

Throw New Win32Exception(Marshal.GetLastWin32Error)

End If

End If

End Sub

'鼠标消息的委托处理代码

Private Function MouseHookProc(ByVal nCode As Integer, ByVal wParam As Integer, ByVal lParam As IntPtr) As Integer

If nCode >= 0 Then

Dim mouseHookStruct As MouseLLHookStruct = DirectCast(Marshal.PtrToStructure(lParam, GetType(MouseLLHookStruct)), MouseLLHookStruct)

Dim moubut As MouseButtons = MouseButtons.None '鼠标按键

Dim mouseDelta As Integer = 0 '滚轮值

Select Case wParam

Case WM_LBUTTONDOWN

moubut = MouseButtons.Left

Case WM_RBUTTONDOWN

moubut = MouseButtons.Right

Case WM_MBUTTONDOWN

moubut = MouseButtons.Middle

Case WM_MOUSEWHEEL

Dim int As Integer = (mouseHookStruct.MouseData >> 16) And &HFFFF

'本段代码CLE添加，模仿C#的Short从Int弃位转换

If int > Short.MaxValue Then mouseDelta = int - 65536 Else mouseDelta = int

End Select

Dim clickCount As Integer = 0 '单击次数

If moubut <> MouseButtons.None Then

If wParam = WM_LBUTTONDBLCLK OrElse wParam = WM_RBUTTONDBLCLK OrElse wParam = WM_MBUTTONDBLCLK Then

clickCount = 2

Else

clickCount = 1

End If

End If

Dim e As New MouseEventArgs(moubut, clickCount, mouseHookStruct.PT.X, mouseHookStruct.PT.Y, mouseDelta)

RaiseEvent MouseActivity(Me, e)

End If

Return CallNextHookEx(hMouseHook, nCode, wParam, lParam) '激活下一个钩子

End Function

''' <summary>键盘钩子是否有效</summary>

Public Property KeyHookEnabled() As Boolean

Get

Return hKeyboardHook <> 0

End Get

Set(ByVal value As Boolean)

If value Then StartHook(True, False) Else UnHook(True, False)

End Set

End Property

''' <summary>鼠标钩子是否有效</summary>

Public Property MouseHookEnabled() As Boolean

Get

Return hMouseHook <> 0

End Get

Set(ByVal value As Boolean)

If value Then StartHook(False, True) Else UnHook(False, True)

End Set

End Property

End Class