Convert-HwndToPid.ps1

Add-Type -TypeDefinition @'
using System;
using System.Runtime.InteropServices;
 
public static class Win32Api
{
[System.Runtime.InteropServices.DllImportAttribute( "User32.dll", EntryPoint =  "GetWindowThreadProcessId" )]
public static extern int GetWindowThreadProcessId ( [System.Runtime.InteropServices.InAttribute()] System.IntPtr hWnd, out int lpdwProcessId );
 
[DllImport("User32.dll", CharSet = CharSet.Auto)]
public static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
}
'@
 
# HWND to PID
function Convert-HwndToPid ($HWND) {
    $HWND | ForEach-Object {
        $myPid = [IntPtr]::Zero;
        $null = [Win32Api]::GetWindowThreadProcessId( $PSItem, [ref] $myPid );
        Select-Object @{n = 'HWND'; e = {$PSItem}}, @{n = 'PID'; e = {$myPid}}, @{n = 'Name'; e = {(Get-Process -PID $myPid).Name}} -InputObject ''
    }
}
 
# Get Microsoft Words HWND
function Get-MsWordHwnd {
    $application = New-Object -ComObject "word.application"
    $caption = [guid]::NewGuid()
    $application.Caption = $caption
    [Win32Api]::FindWindow( 'OpusApp', $caption )
}