UIHelper.cs

#nullable enable
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Automation;

namespace libUIHelper
{
    public static class UIHelper
    {
        public static AutomationElement? FindWindowByTitles(params string[] titles)
        {
            var allWindows = AutomationElement
                                .RootElement
                                .FindAll(TreeScope.Children, new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.Window))
                                .OfType<AutomationElement>()
                                .ToList();

            foreach (var title in titles)
            {
                var window = allWindows.FirstOrDefault(window => window.Current.Name.StartsWith(title));
                if (window != null) return window;
            }

            return null;
        }

        public static AutomationElement GetElementByClassNN(AutomationElement parent, string classNN)
        {
            var result = parent
                            .FindAll(TreeScope.Children, new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.ComboBox))
                            .OfType<AutomationElement>()
                            .Where((element, index) =>
                            {
                                var thisClassNN = $"{element.Current.ClassName}{index + 1}";
                                var match = thisClassNN.Equals(classNN, StringComparison.CurrentCultureIgnoreCase);
                                return match;
                            })
                            .FirstOrDefault();

            return result;
        }

        public static List<string> GetItemsInComboBox(AutomationElement parent, string classNN)
        {
            var control = GetElementByClassNN(parent, classNN);

            var items = control
                            .FindFirst(TreeScope.Children, new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.List))
                            .FindAll(TreeScope.Children, Condition.TrueCondition)
                            .OfType<AutomationElement>()
                            .Select(element => element.Current.Name)
                            .ToList();

            return items;
        }
    }
}