WPFでTextBoxにdoubleをBindingする

System.Windows.FrameworkCompatibilityPreferences
                          .KeepTextBoxDisplaySynchronizedWithTextProperty = false;

<myControl:DoubleTextBox DoubleText="{Binding Double1, UpdateSourceTrigger=PropertyChanged}" />

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;

public class DoubleTextBox : TextBox
{
    public string DoubleText
    {
        get => (string)GetValue(DoubleTextProperty);
        set => SetValue(DoubleTextProperty, value);
    }
    public static readonly DependencyProperty DoubleTextProperty =
          DependencyProperty.Register(
              nameof(DoubleText),
              typeof(string),
              typeof(DoubleTextBox),
              new FrameworkPropertyMetadata(
                  string.Empty,
                  FrameworkPropertyMetadataOptions.BindsTwoWayByDefault | FrameworkPropertyMetadataOptions.Journal,
                  new PropertyChangedCallback(OnDoubleTextChanged),
                  null,
                  true,
                  UpdateSourceTrigger.LostFocus));

    private static void OnDoubleTextChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        if (d is TextBox textBox)
        {
            var currentText = textBox.Text;
            var newText = (string)e.NewValue;
            if (currentText == newText)
                return;
            if (
                double.TryParse(currentText, out var currentDouble) &&
                double.TryParse(newText, out var newDouble) &&
                currentDouble == newDouble
                )
                return;

            textBox.Text = newText;
        }
    }

    protected override void OnTextChanged(TextChangedEventArgs e)
    {
        base.OnTextChanged(e);
        this.DoubleText = this.Text;
    }
}