<Window x:Class="XamlTest.Window1"

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

        xmlns:sys="clr-namespace:System;assembly=mscorlib"

        xmlns:local="clr-namespace:XamlTest"

        Title="Window1" Height="300" Width="300">

    <Grid>

        <StackPanel>

        

            <TextBox Text="{x:Static local:Window1.title}"></TextBox>

            

        </StackPanel>

    </Grid>

</Window>

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Data;

using System.Windows.Documents;

using System.Windows.Input;

using System.Windows.Media;

using System.Windows.Media.Imaging;

using System.Windows.Shapes;

namespace XamlTest

{

    /// <summary>

    /// Interaction logic for Window1.xaml

    /// </summary>

    public partial class Window1 : Window

    {

        public static string title = "wo de title";

        public Window1()

        {

            InitializeComponent();

        }

    }

}