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我想在 vb.NET 2008 中制作一个程序，它将在后台监听键盘，即即使应用程序已最小化（全局）。如果用户按下了特定键，它应该以固定的给定时间间隔继续触发其他 2 个键，直到用户再次按下该特定键。

这如何在 vb.NET 2008 中完成？

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2 回答 2

16

来源：这里

用法：创建钩子

Private WithEvents kbHook As New KeyboardHook

然后可以处理每个事件：

Private Sub kbHook_KeyDown(ByVal Key As System.Windows.Forms.Keys) Handles kbHook.KeyDown
    Debug.WriteLine(Key.ToString) 
End Sub 
Private Sub kbHook_KeyUp(ByVal Key As System.Windows.Forms.Keys) Handles kbHook.KeyUp 
    Debug.WriteLine(Key) 
End Sub

键盘挂钩类：

Imports System.Runtime.InteropServices

Public Class KeyboardHook

    <DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)> _
    Private Overloads Shared Function SetWindowsHookEx(ByVal idHook As Integer, ByVal HookProc As KBDLLHookProc, ByVal hInstance As IntPtr, ByVal wParam As Integer) As Integer
    End Function
    <DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)> _
    Private Overloads Shared Function CallNextHookEx(ByVal idHook As Integer, ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
    End Function
    <DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)> _
    Private Overloads Shared Function UnhookWindowsHookEx(ByVal idHook As Integer) As Boolean
    End Function

    <StructLayout(LayoutKind.Sequential)> _
    Private Structure KBDLLHOOKSTRUCT
        Public vkCode As UInt32
        Public scanCode As UInt32
        Public flags As KBDLLHOOKSTRUCTFlags
        Public time As UInt32
        Public dwExtraInfo As UIntPtr
    End Structure

    <Flags()> _
    Private Enum KBDLLHOOKSTRUCTFlags As UInt32
        LLKHF_EXTENDED = &H1
        LLKHF_INJECTED = &H10
        LLKHF_ALTDOWN = &H20
        LLKHF_UP = &H80
    End Enum

    Public Shared Event KeyDown(ByVal Key As Keys)
    Public Shared Event KeyUp(ByVal Key As Keys)

    Private Const WH_KEYBOARD_LL As Integer = 13
    Private Const HC_ACTION As Integer = 0
    Private Const WM_KEYDOWN = &H100
    Private Const WM_KEYUP = &H101
    Private Const WM_SYSKEYDOWN = &H104
    Private Const WM_SYSKEYUP = &H105

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

    Private KBDLLHookProcDelegate As KBDLLHookProc = New KBDLLHookProc(AddressOf KeyboardProc)
    Private HHookID As IntPtr = IntPtr.Zero

    Private Function KeyboardProc(ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
        If (nCode = HC_ACTION) Then
            Dim struct As KBDLLHOOKSTRUCT
            Select Case wParam
                Case WM_KEYDOWN, WM_SYSKEYDOWN
                    RaiseEvent KeyDown(CType(CType(Marshal.PtrToStructure(lParam, struct.GetType()), KBDLLHOOKSTRUCT).vkCode, Keys))
                Case WM_KEYUP, WM_SYSKEYUP
                    RaiseEvent KeyUp(CType(CType(Marshal.PtrToStructure(lParam, struct.GetType()), KBDLLHOOKSTRUCT).vkCode, Keys))
            End Select
        End If
        Return CallNextHookEx(IntPtr.Zero, nCode, wParam, lParam)
    End Function

    Public Sub New()
        HHookID = SetWindowsHookEx(WH_KEYBOARD_LL, KBDLLHookProcDelegate, System.Runtime.InteropServices.Marshal.GetHINSTANCE(System.Reflection.Assembly.GetExecutingAssembly.GetModules()(0)).ToInt32, 0)
        If HHookID = IntPtr.Zero Then
            Throw New Exception("Could not set keyboard hook")
        End If
    End Sub

    Protected Overrides Sub Finalize()
        If Not HHookID = IntPtr.Zero Then
            UnhookWindowsHookEx(HHookID)
        End If
        MyBase.Finalize()
    End Sub

End Class
于 2013-02-23T09:03:40.647 回答
0

如果您使用 KeyboardHook 类，请确保您必须在使用前构建您的程序。对于特定键的问题，您可以在 KeyDown 或 KeyUp 事件中触发它。但在此之前，您必须使用 sendkeys 将密钥发送到活动窗口。

SendKeys.Send("L") '将字母 L 发送到活动窗口。

然后您可以执行以下代码；下面检查是否按下了字母“a”。

Private Sub kbHook_KeyDown(ByVal Key As System.Windows.Forms.Keys) Handles kbHook.KeyDown
    Debug.WriteLine(Key.ToString) 
    if Key.ToString() = "a" then
     'trigger your sendkeys
    end if
End Sub

要触发特定键（如切换按钮），只需声明一个布尔变量来检查按钮是否被切换。您可以全局声明它：

将开关调暗为 boolean = false

只需更新您设置条件以检查按下的字母的区域。如下所示：

if Key.ToString() = "a" then
  if switch = false then
    switch = true
    'trigger send keys
  else
    switch = false
    'deactivate send keys
  end if
end if

要确定发送密钥的特定时间，请使用计时器。我希望它有所帮助。

于 2016-10-18T09:46:39.233 回答