WPF Demo13通知项属性+数据绑定(代码层)

<Window x:Class="BindingDemo1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="254" Width="430" Loaded="Window_Loaded">
    <Grid Name="gr">
        <Button Content="name" Height="23" HorizontalAlignment="Left" Margin="48,65,0,0" Name="button1" VerticalAlignment="Top" Width="75" Click="button1_Click" />
        <TextBox Height="23" HorizontalAlignment="Left" Margin="48,12,0,0" Name="txtName"  VerticalAlignment="Top" Width="333" />
        <Button Content="age" Height="23" HorizontalAlignment="Left" Margin="48,169,0,0" Name="button2" VerticalAlignment="Top" Width="75" Click="button2_Click" />
        <TextBox Height="23" HorizontalAlignment="Left" Margin="48,116,0,0" Name="txtAge" VerticalAlignment="Top" Width="333" />
    </Grid>
</Window>

using System.ComponentModel;

namespace BindingDemo1
{
    class Student : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;

        private string name;
        public string Name
        {
            get { return name; }
            set
            {
                name = value;
                if (this.PropertyChanged != null)
                {
                    this.PropertyChanged.Invoke(this, new PropertyChangedEventArgs("Name"));
                }
            }
        }

        private int age;
        public int Age
        {
            get { return age; }
            set
            {
                age = value;
                if (this.PropertyChanged != null)
                {
                    this.PropertyChanged.Invoke(this, new PropertyChangedEventArgs("Age"));
                }
            }
        }
    }
}

using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;

namespace BindingDemo1
{
    /// <summary>
    /// MainWindow.xaml 的交互逻辑
    /// </summary>
    public partial class MainWindow : Window
    {
        Student stu = new Student();
        public MainWindow()
        {
            InitializeComponent();

            this.DataContext = stu;

            this.txtName.SetBinding(TextBox.TextProperty, new Binding("Name"));
            this.txtAge.SetBinding(TextBox.TextProperty, new Binding("Age"));
        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            stu.Name += "testName";
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            stu.Age += 10;
            stu.Name += "testName";
        }

        private void button2_Click(object sender, RoutedEventArgs e)
        {
            stu.Age += 10;
        }
    }
}

INotifyPropertyChanged 接口用于向客户端（通常是执行绑定的客户端）发出某一属性值已更改的通知。

使用方式(操作步骤)：
1. 定义(类必须继承INotifyPropertyChanged接口)
2. 页面实例化
3. XAML UI 绑定
4. 其他 UI 改变其绑定值

注意：
以上操作可参考“实例一”中描述；
通知项属性用于不同UI中动态改变绑定信息；
INotifyPropertyChanged为接口，PropertyChanged为事件，在更改属性值时触发(PropertyChanged 事件
可以通过将 null或 String. Empty 用作 PropertyChangedEventArgs 中的属性名，指示该对象上的所有属性
都已更改)；