WPF中监视DependencyProperty的变化

              WPF中监视DependencyProperty的变化

                     周银辉

 

尽管一个类会提供很多事件,但有时候还是显得不够,比如说前两天我就以为WPF的ListBox控件会有ItemsSourceChanged事件,但好像没有。这里有一个方法可以监视任何一个DependencyProperty的Changed,下面是demo:

    public class People : DependencyObject
    {
        public static readonly DependencyProperty NameProperty =
            DependencyProperty.Register("Name", typeof (string), typeof (People), new PropertyMetadata(default(string)));

        public string Name
        {
            get { return (string) GetValue(NameProperty); }
            set { SetValue(NameProperty, value); }
        }
    }

//.........
        private void ButtonBase_OnClick(object sender, RoutedEventArgs e)
        {
            var people = new People {Name = "zhang san"};

            var descriptor =  DependencyPropertyDescriptor.FromProperty(People.NameProperty, typeof (People));
            descriptor.AddValueChanged(people, (o, args) => MessageBox.Show("name changed to " + people.Name));

            people.Name = "Li si";
        }

 

 

 

posted @ 2014-07-08 09:46  周银辉  阅读(4001)  评论(0编辑  收藏