Refresh the Windows environment variables from the registry

Refresh-Environment.ps1

<#
.SYNOPSIS
Refresh the Windows environment variables from the registry.

.DESCRIPTION
Refresh the Windows environment variables from the registry.

.INPUTS
None.

.OUTPUTS
None.
#>

using namespace RefreshEnvironment

$source = @"
using System;
using System.Runtime.InteropServices;

namespace RefreshEnvironment
{
    public class RefreshEnvironment
    {
        public static readonly IntPtr HWND_BROADCAST = (IntPtr)0xffff;

        public const uint WM_WININICHANGE = 0x001A;
        public const uint WM_SETTINGCHANGE = WM_WININICHANGE;

        [Flags]
        public enum SendMessageTimeoutFlags : uint
        {
            SMTO_NORMAL             = 0x0,
            SMTO_BLOCK              = 0x1,
            SMTO_ABORTIFHUNG        = 0x2,
            SMTO_NOTIMEOUTIFNOTHUNG = 0x8,
            SMTO_ERRORONEXIT = 0x20
        }

        [DllImport("user32.dll", CharSet=CharSet.Auto, SetLastError=true)]
        public static extern IntPtr SendMessageTimeout(
            IntPtr hWnd,
            uint Msg,
            UIntPtr wParam,
            string lParam,
            SendMessageTimeoutFlags fuFlags,
            uint uTimeout,
            out UIntPtr lpdwResult
        );
    }
}
"@

Add-Type -TypeDefinition $source

$result = [UIntPtr]::Zero
if (![RefreshEnvironment]::SendMessageTimeout(
    [RefreshEnvironment]::HWND_BROADCAST,
    [RefreshEnvironment]::WM_SETTINGCHANGE,
    [UIntPtr]::Zero,
    "Environment",
    [RefreshEnvironment+SendMessageTimeoutFlags]::SMTO_ABORTIFHUNG,
    5000,
    [ref]$result
)) {
    throw [ComponentModel.Win32Exception]::new([Marshal]::GetLastWin32Error())
}