在更新了多个其他TextBoxes中的任何一个之后更新TextBox的值

textBox1.TextChanged += TextBox_TextChanged;
textBox2.TextChanged += TextBox_TextChanged;
// 其他文本框的事件监听器设置

<TextBox Text="{Binding Path=Value, Mode=TwoWay}" />

private void TextBox_TextChanged(object sender, EventArgs e)
{
    if (sender != textBoxToUpdate)
    {
        textBoxToUpdate.Text = CalculateNewValue();
    }
}

public class MyViewModel : INotifyPropertyChanged
{
    private string _value;
    public string Value
    {
        get { return _value; }
        set
        {
            if (_value != value)
            {
                _value = value;
                OnPropertyChanged(nameof(Value));
            }
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;
    protected void OnPropertyChanged(string propertyName)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

<Window x:Class="TextBoxUpdateExample.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="200" Width="400">
    <StackPanel>
        <TextBox x:Name="textBox1" Text="{Binding Value, Mode=TwoWay}" />
        <TextBox x:Name="textBox2" Text="{Binding Value, Mode=TwoWay}" />
        <TextBox x:Name="textBoxToUpdate" />
    </StackPanel>
</Window>

public partial class MainWindow : Window
{
    private MyViewModel viewModel = new MyViewModel();

    public MainWindow()
    {
        InitializeComponent();
        DataContext = viewModel;

        textBox1.TextChanged += TextBox_TextChanged;
        textBox2.TextChanged += TextBox_TextChanged;
    }

    private void TextBox_TextChanged(object sender, EventArgs e)
    {
        if (sender != textBoxToUpdate)
        {
            textBoxToUpdate.Text = viewModel.Value;
        }
    }
}