DependencyProperty使用中的3个场景，讨论PropertyChangedCallback

1：项目结构图

2：控件SilverlightControl1

前台：

后台：

public partial class SilverlightControl1 : UserControl
{
    public SilverlightControl1()
    {
        InitializeComponent();
    }
 
    public static readonly DependencyProperty StudentProperty = DependencyProperty.Register("Student", typeof(Student), typeof(SilverlightControl1), new PropertyMetadata(new PropertyChangedCallback(xxx)));
 
    public Student Student
    {
        get
        {
            return (Student)GetValue(StudentProperty);
        }
        set
        {
            SetValue(StudentProperty, value);
             
        }
    }
 
    static void xxx(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        MessageBox.Show("sss");
    }
}

3：调用方

前台：

后台：

public partial class MainPage : UserControl
{
    public MainPage()
    {
        InitializeComponent();
    }
 
    Student student1 = new Student() { StudentName = "hzh" + DateTime.Now.ToFileTime(), Age = 99 };
    Student student2 = new Student() { StudentName = "lmj" + DateTime.Now.ToFileTime(), Age = 99 };
    Student student3 = new Student() { StudentName = "lh" + DateTime.Now.ToFileTime(), Age = 99 };
 
    //初始化
    private void Button_Click(object sender, RoutedEventArgs e)
    {
        //采用非绑定机制
        uc1.Student = student1;
        //采用非绑定机制，对DataContext赋值
        uc2.DataContext = student2;
        //采用绑定机制
        uc3.DataContext = student3;
    }
 
    //改Model值
    private void Button_Click1(object sender, RoutedEventArgs e)
    {
        student1.StudentName = "lmj" + DateTime.Now.ToString();
        student1.Age = 90;
        student2.StudentName = "hzh" + DateTime.Now.ToString();
        student2.Age = 90;
        student3.StudentName = "hzh" + DateTime.Now.ToString();
        student3.Age = 90;
    }
 
    //更换Model
    private void Button_Click_1(object sender, RoutedEventArgs e)
    {
        student1 = new Student() { StudentName = "hzh" + DateTime.Now.ToFileTime(), Age = 99 };
        student2 = new Student() { StudentName = "lmj" + DateTime.Now.ToFileTime(), Age = 99 };
        student3 = new Student() { StudentName = "lh" + DateTime.Now.ToFileTime(), Age = 99 };
    }
}