WPF/C#将两个文本框中的内容绑定到单个标签

<StackPanel>
    <TextBox x:Name="textBox1" Text="{Binding Text1}" />
    <TextBox x:Name="textBox2" Text="{Binding Text2}" />
    <Label Content="{Binding CombinedText}" />
</StackPanel>

public class ViewModel : INotifyPropertyChanged
{
    private string text1;
    private string text2;

    public string Text1
    {
        get { return text1; }
        set
        {
            text1 = value;
            OnPropertyChanged(nameof(Text1));
            OnPropertyChanged(nameof(CombinedText));
        }
    }

    public string Text2
    {
        get { return text2; }
        set
        {
            text2 = value;
            OnPropertyChanged(nameof(Text2));
            OnPropertyChanged(nameof(CombinedText));
        }
    }

    public string CombinedText
    {
        get { return $"{Text1} {Text2}"; }
    }

    public event PropertyChangedEventHandler PropertyChanged;

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

public MainWindow()
{
    InitializeComponent();
    DataContext = new ViewModel();
}