正如我在我的評論中所說keybd_event()已棄用，由SendInput()替代。但是，您收到PInvokeStackImbalance異常的原因是因爲函數聲明中最後兩個參數是錯誤的。
幾乎所有Declare...Lib的例子都是針對VB 6或更低版本設計的，例如Long與VB.NET的Long數據類型不一樣。我建議你到總是尋找P/Invoke片段使用DllImport attribute。如果找不到VB.NET版本，則可以查找C＃代碼片段，然後使用在線轉換器轉換它們。
要修復錯誤，最後兩個參數應該是UInteger和UIntPtr。
Public Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As UInteger, ByVal dwExtraInfo As UIntPtr)
然而，正如我說的，建議堅持DllImport：
<DllImport("user32.dll")> _
Public Shared Sub keybd_event(bVk As Byte, bScan As Byte, dwFlags As UInteger, dwExtraInfo As UIntPtr)
End Function
您可以檢查pinvoke.net對於P/Invoke的片段。
要使用今天推薦的方法SendInput()，你可以利用我的InputHelper類：
Imports System.Runtime.InteropServices
Public NotInheritable Class InputHelper
Private Sub New()
End Sub
#Region "Methods"
#Region "PressKey()"
''' <summary>
''' Virtually presses a key.
''' </summary>
''' <param name="Key">The key to press.</param>
''' <param name="HardwareKey">Whether or not to press the key using its hardware scan code.</param>
''' <remarks></remarks>
Public Shared Sub PressKey(ByVal Key As Keys, Optional ByVal HardwareKey As Boolean = False)
If HardwareKey = False Then
InputHelper.SetKeyState(Key, False)
InputHelper.SetKeyState(Key, True)
Else
InputHelper.SetHardwareKeyState(Key, False)
InputHelper.SetHardwareKeyState(Key, True)
End If
End Sub
#End Region
#Region "SetKeyState()"
''' <summary>
''' Virtually sends a key event.
''' </summary>
''' <param name="Key">The key of the event to send.</param>
''' <param name="KeyUp">Whether to push down or release the key.</param>
''' <remarks></remarks>
Public Shared Sub SetKeyState(ByVal Key As Keys, ByVal KeyUp As Boolean)
Key = ReplaceBadKeys(Key)
Dim KeyboardInput As New KEYBDINPUT With {
.wVk = Key,
.wScan = 0,
.time = 0,
.dwFlags = If(KeyUp, KEYEVENTF.KEYUP, 0),
.dwExtraInfo = IntPtr.Zero
}
Dim Union As New INPUTUNION With {.ki = KeyboardInput}
Dim Input As New INPUT With {
.type = INPUTTYPE.KEYBOARD,
.U = Union
}
SendInput(1, New INPUT() {Input}, Marshal.SizeOf(GetType(INPUT)))
End Sub
#End Region
#Region "SetHardwareKeyState()"
''' <summary>
''' Virtually sends a key event using the key's scan code.
''' </summary>
''' <param name="Key">The key of the event to send.</param>
''' <param name="KeyUp">Whether to push down or release the key.</param>
''' <remarks></remarks>
Public Shared Sub SetHardwareKeyState(ByVal Key As Keys, ByVal KeyUp As Boolean)
Key = ReplaceBadKeys(Key)
Dim KeyboardInput As New KEYBDINPUT With {
.wVk = 0,
.wScan = MapVirtualKeyEx(CUInt(Key), 0, GetKeyboardLayout(0)),
.time = 0,
.dwFlags = KEYEVENTF.SCANCODE Or If(KeyUp, KEYEVENTF.KEYUP, 0),
.dwExtraInfo = IntPtr.Zero
}
Dim Union As New INPUTUNION With {.ki = KeyboardInput}
Dim Input As New INPUT With {
.type = INPUTTYPE.KEYBOARD,
.U = Union
}
SendInput(1, New INPUT() {Input}, Marshal.SizeOf(GetType(INPUT)))
End Sub
#End Region
#Region "ReplaceBadKeys()"
''' <summary>
''' Replaces bad keys with their corresponding VK_* value.
''' </summary>
''' <remarks></remarks>
Private Shared Function ReplaceBadKeys(ByVal Key As Keys) As Keys
Dim ReturnValue As Keys = Key
If ReturnValue.HasFlag(Keys.Control) Then
ReturnValue = (ReturnValue And Not Keys.Control) Or Keys.ControlKey 'Replace Keys.Control with Keys.ControlKey.
End If
If ReturnValue.HasFlag(Keys.Shift) Then
ReturnValue = (ReturnValue And Not Keys.Shift) Or Keys.ShiftKey 'Replace Keys.Shift with Keys.ShiftKey.
End If
If ReturnValue.HasFlag(Keys.Alt) Then
ReturnValue = (ReturnValue And Not Keys.Alt) Or Keys.Menu 'Replace Keys.Alt with Keys.Menu.
End If
Return ReturnValue
End Function
#End Region
#End Region
#Region "WinAPI P/Invokes"
<DllImport("user32.dll", SetLastError:=True)>
Private Shared Function SendInput(ByVal nInputs As UInteger, <MarshalAs(UnmanagedType.LPArray)> ByVal pInputs() As INPUT, ByVal cbSize As Integer) As UInteger
End Function
<DllImport("user32.dll")> _
Private Shared Function MapVirtualKeyEx(uCode As UInteger, uMapType As UInteger, dwhkl As IntPtr) As UInteger
End Function
<DllImport("user32.dll")> _
Private Shared Function GetKeyboardLayout(idThread As UInteger) As IntPtr
End Function
#Region "Enumerations"
Private Enum INPUTTYPE As UInteger
MOUSE = 0
KEYBOARD = 1
HARDWARE = 2
End Enum
<Flags()> _
Private Enum KEYEVENTF As UInteger
EXTENDEDKEY = &H1
KEYUP = &H2
SCANCODE = &H8
UNICODE = &H4
End Enum
#End Region
#Region "Structures"
<StructLayout(LayoutKind.Explicit)> _
Private Structure INPUTUNION
<FieldOffset(0)> Public mi As MOUSEINPUT
<FieldOffset(0)> Public ki As KEYBDINPUT
<FieldOffset(0)> Public hi As HARDWAREINPUT
End Structure
Private Structure INPUT
Public type As Integer
Public U As INPUTUNION
End Structure
Private Structure MOUSEINPUT
Public dx As Integer
Public dy As Integer
Public mouseData As Integer
Public dwFlags As Integer
Public time As Integer
Public dwExtraInfo As IntPtr
End Structure
Private Structure KEYBDINPUT
Public wVk As UShort
Public wScan As Short
Public dwFlags As UInteger
Public time As Integer
Public dwExtraInfo As IntPtr
End Structure
Private Structure HARDWAREINPUT
Public uMsg As Integer
Public wParamL As Short
Public wParamH As Short
End Structure
#End Region
#End Region
End Class
例如：
If condition = True Then
InputHelper.SetKeyState(Keys.Scroll, False) 'Key down.
Else
InputHelper.SetKeyState(Keys.Scroll, True) 'Key up.
End If
'keybd_event'已被棄用，所以是'聲明。 ..Lib'。當前發送鍵盤/鼠標事件的方法是使用[**'SendInput（）'**]（https://msdn.microsoft.com/en-us/library/windows/desktop/ms646310（v = vs。 85）的.aspx）。看到我的鍵盤輸入包裝[**在這個答案**]（http://stackoverflow.com/questions/39809095/why-do-some-applications-not-accept-some-sendkeys-at-some-times/39811061 ＃39811061）。 –
看看這個例子： https://msdn.microsoft.com/en-us/library/windows/desktop/ms646304(v=vs.85).aspx 這是爲numloc，但根據您應該使用KEYEVENTF_EXTENDEDKEY的信息。 第二：COndition的背後是什麼？是這樣的： GetKeyboardState（（LPBYTE）＆keyState）;例如。獲取當前的關鍵狀態？ 第三，您可以嘗試使用SetInput而不是keybg_event，因爲keybg_event被取代 – Kiko
如果函數被正確聲明，則根本沒有錯誤。 「Thrown」複選框在默認情況下不應該勾選任何異常，因爲即使處理異常，它也會中斷應用程序。 –