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.NET Framework Class Library
Control..::.IsKeyLocked Method

Determines whether the CAPS LOCK, NUM LOCK, or SCROLL LOCK key is in effect.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
Syntax
Public Shared Function IsKeyLocked ( _
	keyVal As Keys _
) As Boolean
public static bool IsKeyLocked(
	Keys keyVal
)
public:
static bool IsKeyLocked(
	Keys keyVal
)
static member IsKeyLocked : 
        keyVal:Keys -> bool 

Parameters

keyVal
Type: System.Windows.Forms..::.Keys
The CAPS LOCK, NUM LOCK, or SCROLL LOCK member of the Keys enumeration.

Return Value

Type: System..::.Boolean
true if the specified key or keys are in effect; otherwise, false.
Exceptions
ExceptionCondition
NotSupportedException

The keyVal parameter refers to a key other than the CAPS LOCK, NUM LOCK, or SCROLL LOCK key.

Remarks

Use the IsKeyLocked property to determine whether the CAPS LOCK, NUM LOCK, or SCROLL LOCK keys are on, whether individually or in combination.

Examples

The following code example displays a message box indicating whether the specified key (the Caps Lock key in this case) is in effect.



' To compile and run this sample from the command line, proceed as follows:
' vbc controliskeylocked.vb /r:System.Windows.Forms.dll /r:System.dll 
' /r:System.Data.dll /r:System.Drawing.dll

Imports System
Imports System.Windows.Forms
Imports Microsoft.VisualBasic

Public Class CapsLockIndicator

    Public Shared Sub Main()
        if Control.IsKeyLocked(Keys.CapsLock) Then
            MessageBox.Show("The Caps Lock key is ON.")
        Else
            MessageBox.Show("The Caps Lock key is OFF.")
        End If
    End Sub 'Main
End Class 'CapsLockIndicator


using System;
using System.Windows.Forms;

public class CapsLockIndicator
{
    public static void Main()
    {
        if (Control.IsKeyLocked(Keys.CapsLock)) {
            MessageBox.Show("The Caps Lock key is ON.");
        }
        else {
            MessageBox.Show("The Caps Lock key is OFF.");
        }
    }
}


#using <System.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>

using namespace System;
using namespace System::Windows::Forms;
int main()
{
   if (Control::IsKeyLocked( Keys::CapsLock )) {
      MessageBox::Show( "The Caps Lock key is ON." );
   }
   else { 
      MessageBox::Show( "The Caps Lock key is OFF." );
   }

}


Version Information

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
Platforms

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.