C# WPF 测试直接绑定依赖属性双向传递是没有问题的

续这篇测试：https://www.cnblogs.com/huvjie/p/16909290.html

测试页面：

<Window x:Class="MyWPFSimple3.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:MyWPFSimple3"
        mc:Ignorable="d"
        Title="MainWindow" Height="170" Width="300">
    <Grid>
        <StackPanel HorizontalAlignment="Center" Margin="5">
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="姓名：" VerticalAlignment="Center"/>
                <TextBox BorderBrush="Black" Height="30" Width="150" VerticalContentAlignment="Center"
                         Text="{Binding RelativeSource={RelativeSource AncestorType={x:Type Window}, Mode=FindAncestor}, Path=PersonName}"/>
            </StackPanel>
            <StackPanel Orientation="Horizontal" Margin="0 2 0 0">
                <TextBlock Text="年龄：" VerticalAlignment="Center"/>
                <TextBox BorderBrush="Black" Height="30" Width="150" VerticalContentAlignment="Center" 
                          Text="{Binding RelativeSource={RelativeSource AncestorType={x:Type Window}, Mode=FindAncestor}, Path=PersonAge}" />
            </StackPanel>
            <Button x:Name="btn_ChangeInfo" Click="btn_ChangeInfo_Click" Content="Change Info" Width="186" Margin="0 5 0 0"/>
            <Button x:Name="btn_ShowInfo" Click="btn_ShowInfo_Click"  Content="Show Info" Width="186" Margin="0 5 0 0"/>
        </StackPanel>
    </Grid>
</Window>

BehindCode:

using System;
using System.Collections.Generic;
using System.ComponentModel;
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.Navigation;
using System.Windows.Shapes;

namespace MyWPFSimple3
{
    /// <summary>
    /// MainWindow.xaml 的交互逻辑
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        public string PersonName
        {
            get
            {
                return (string)GetValue(PersonNameProperty);
            }
            set
            {
                SetValue(PersonNameProperty, value);
            }
        }

        // Using a DependencyProperty as the backing store for PersonName.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty PersonNameProperty =
            DependencyProperty.Register("PersonName", typeof(string), typeof(MainWindow), new PropertyMetadata("悟空"));

        public int PersonAge
        {
            get
            {
                return (int)GetValue(PerAgeProperty);
            }
            set
            {
                SetValue(PerAgeProperty, value);
            }
        }

        // Using a DependencyProperty as the backing store for PerAge.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty PerAgeProperty =
            DependencyProperty.Register("PersonAge", typeof(int), typeof(MainWindow), new PropertyMetadata(500));

        public event PropertyChangedEventHandler PropertyChanged;

        protected virtual void RaisePropertyChanged(string propertyName)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }

        private void btn_ChangeInfo_Click(object sender, RoutedEventArgs e)
        {
            PersonName = "玄奘";
            PersonAge = 25;
        }

        private void btn_ShowInfo_Click(object sender, RoutedEventArgs e)
        {
            MessageBox.Show($"姓名：{PersonName}\r\n年龄：{PersonAge}\r\n");
        }
    }
}