An Introduction to Managed Extensibility Framework (MEF) - Part I

using System;
using System.Windows;
using CompositionHelper;


namespace CalculatorUI
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        CalciCompositionHelper objCompHelper;

        public MainWindow()
        {
            InitializeComponent();
        }

        private void btnAdd_Click(object sender, RoutedEventArgs e)
        {

            objCompHelper = new CalciCompositionHelper();

            //Assembles the calculator components that will participate in composition
            objCompHelper.AssembleCalculatorComponents();

            //Gets the result
            var result = objCompHelper.GetResult(Convert.ToInt32(txtFirstNumber.Text), Convert.ToInt32(txtSecondNumber.Text));

            //Display the result
            txtResult.Text = result.ToString();
        }
    }
}