我正在尝试将自定义类型的属性绑定到用户控件（在我们的示例中，我们将其称为DataContextOne）。此自定义类型由两个字符串组成。

然后，我有一个要将此自定义类型绑定到的用户控件。

奇怪的是，如果我放入我的控件 2 个字符串属性，然后尝试从我的自定义类型绑定每个字符串，它就会起作用。但是，当我在自定义控件中仅创建一个 DataContextOne 属性并尝试绑定到它时，没有任何反应（= 用户控件中的 null）。

这是我的代码

DataContextOne

public class DataContextOne : INotifyPropertyChanged
{
    protected virtual void RaisePropertyChanged(string propertyName)
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    }
    public event PropertyChangedEventHandler PropertyChanged;
    private string _title;
    public string Title 
    {
        get { return _title; }
        set
        {
            if (_title != value)
            {
                _title = value;
                TitleModified = _title + " modified";
                RaisePropertyChanged("Title");
            }
        }
    }
    private string _titlemodified;
    public string TitleModified
    {
        get { return _titlemodified; }
        set
        {
            if (_titlemodified != value)
            {
                _titlemodified = value;
                RaisePropertyChanged("TitleModified");
            }
        }
    }
}

有效的绑定

用户控件

public partial class MyUserControl : UserControl
{
    public MyUserControl()
    {
        InitializeComponent();
        (Content as FrameworkElement).DataContext = this;
    }
    public string Text
    {
        get { return (string)GetValue(TextProperty); }
        set { SetValue(TextProperty, value); }
    }
    public static readonly DependencyProperty TextProperty = DependencyProperty.Register(
            "Text",
            typeof(string),
            typeof(MyUserControl),
            null);
    public string TextModified
    {
        get { return (string)GetValue(TextModifiedProperty); }
        set { SetValue(TextModifiedProperty, value); }
    }
    public static readonly DependencyProperty TextModifiedProperty = DependencyProperty.Register(
            "TextModified",
            typeof(string),
            typeof(MyUserControl),
            null);
}

主窗口

代码隐藏

public partial class MainWindow : Window
{
    Random Rnd = new Random();
    DataContextOne dtone = new DataContextOne();
    public MainWindow()
    {
        InitializeComponent();
        dtone.Title = Rnd.Next().ToString();
        DataContext = dtone;
    }
    private void Button_Click(object sender, RoutedEventArgs e)
    {
        dtone.Title = Rnd.Next().ToString();
    }
}

XAML：

<local:MyUserControl Grid.Row="1" Text="{Binding Title, UpdateSourceTrigger=PropertyChanged}" TextModified="{Binding TitleModified, UpdateSourceTrigger=PropertyChanged}"/>

绑定不起作用

用户控制

public partial class MyUserControl : UserControl
{
    public MyUserControl()
    {
        InitializeComponent();
        (Content as FrameworkElement).DataContext = this;
    }
    public DataContextOne dtone 
    {
        get { return (DataContextOne)GetValue(dtoneProperty); }
        set { SetValue(dtoneProperty, value); }
    }
    public static readonly DependencyProperty dtoneProperty = DependencyProperty.Register(
            "dtone",
            typeof(DataContextOne),
            typeof(MyUserControl),
            null);
}

主窗口

代码隐藏（注意我绑定了this）

public partial class MainWindow : Window
{
    Random Rnd = new Random();
    DataContextOne dtone = new DataContextOne();
    public MainWindow()
    {
        InitializeComponent();
        dtone.Title = Rnd.Next().ToString();
        DataContext = this;
    }
    private void Button_Click(object sender, RoutedEventArgs e)
    {
        dtone.Title = Rnd.Next().ToString();
    }
}

XAML

<local:MyUserControl Grid.Row="1" dtone="{Binding dtone, UpdateSourceTrigger=PropertyChanged}" Margin="0,31,200,169"/>

我不明白缺少什么。对我来说，这只是一个封装第二个版本字符串的自定义类型，这是一回事，那么为什么它不起作用呢？

<local:MyUserControl Grid.Row="1" DataContext="{Binding dtone}" />