Chomo.Window1.btnSource_Click C# (CSharp) Method

        private void btnSource_Click(object sender, RoutedEventArgs e)
        {
            var openFileDialog = new Microsoft.Win32.OpenFileDialog();
            openFileDialog.FileName = "Select File to Convert";

            Nullable<bool> result = openFileDialog.ShowDialog();

            if (result == true)
            {
                entSource.Text = openFileDialog.FileName.ToLower();
                if (!(entSource.Text.EndsWith(".shp") ||
                       entSource.Text.EndsWith(".kml")))
                {
                    entSource.Text = "Extension Must be SHP or KML";
                    btnConvert.IsEnabled = false;
                }

                else
                {
                    if (entDestination.Text.EndsWith(".shp") ||
                           entDestination.Text.EndsWith(".kml"))
                    {
                        btnConvert.IsEnabled = true;
                    }
                }
            }
        }