如何使用 powershell 在远程计算机上获取 Caps Lock 状态

Question

I have tried the following command but I only get a value of False :

Invoke-Command -ComputerName Server01  -ScriptBlock {[console]::CapsLock} 

When I run [console]::CapsLock locally the command works.

Answer 1

Using [Console]::CapsLock

The [Console]::CapsLock property can be read to get whether CapsLock is On or Off ( $true or $false ):

[Console]::CapsLock

You can also check the state of NumLock with [Console]::NumberLock as well.

Using MS Word

Seems that the remote session doesn't reflect whether CapsLock is on or off based on whether the physical keyboard has it on or off.

I was able to find another method but don't have a way to test it myself, and it requires Microsoft Word to be installed:

$word = New-Object -ComObject "Word.Application"

# Check CapsLock
$word.CapsLock

# Check NumLock
$word.NumLock

Using the System.Windows.Forms Namespace

A third method that might work for your needs would be to use the System.Windows.Forms namespace to read the caps lock setting.

# Make System.Windows.Forms available in Powershell
Add-Type -AssemblyName System.Windows.Forms

# Check CapsLock
[System.Windows.Forms.Control]::IsKeyLocked( 'CapsLock' )

# Check NumLock
[System.Windows.Forms.Control]::IsKeyLocked( 'NumLock' )

Using the Win32 API

You can also check the state using the Win32 API:

# Compile some quick C# so we can `P/Invoke` to the native library
$signature = @"
[DllImport("USER32.dll")]                            
public static extern short GetKeyState(int nVirtKey);
"@
$Kernel32 = Add-Type -MemberDefinition $signature -Name Kernel32 -Namespace Win32 -Passthru

# Check CapsLock
[bool]( $Kernel32::GetKeyState(0x14) )

# Check NumLock
[bool]( $Kernel32::GetKeyState(0x90) )

0x14 is the key id for CapsLock and 0x90 is the key id for NumLock . See this page for more information on making use of this API from .NET , and this page for the documentation of GetKeyState itself .

Doing it remotely

I could not find any reliable methods of doing this remotely, which makes sense, as CapsLock is a per session setting - not a system wide one. Even assuming there is a way to get the CapsLock status for a given active session, you could have several user sessions on one remote system at once, and it becomes difficult to know which session to look at for its CapsLock status.