C# INotifyPropertyChanged用法，监听属性值发生改变

有时候，我们需要监听属性值的变化，当属性值发生改变时，需要被通知，没有改变时不需要通知，这个时候可以用INotifyPropertyChanged来做，也可以自定义委托事件，也可以实现，方法多多，在这里只介绍INotifyPropertyChanged的方法，目的是当属性值发生变化时，才触发事件

案例: 创建一个父类Person，继承INotifyPropertyChanged类，然后让Man类去继承
Person类：

using System;
using System.Collections.Generic;
using System.Text;
using System.ComponentModel;
namespace Demo
{
    public delegate void ChangedHandler(object sender, object v);
    public class Person : INotifyPropertyChanged
    {
        #region INotifyPropertyChanged 成员
        public event PropertyChangedEventHandler PropertyChanged;
        public virtual void OnPropertyChanged(string propertyName)
        {
            PropertyChangedEventHandler hander = PropertyChanged;
            if (hander != null)
                hander(this, new PropertyChangedEventArgs(propertyName));
        }
        #endregion
        /// <summary>
        /// 属性变换事件
        /// </summary>
        /// <param name="sender">源</param>
        /// <param name="v">变化后的值</param>
        /// <param name="old">变化前的值</param>
        /// <param name="hander"></param>
        protected virtual void OnChanged(object sender, object v, object old, ChangedHandler hander)
        {
            if (!v.Equals(old) && hander != null)
                hander(sender, v);
        }
    }
}

Man类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Demo
{
    public class Man:Person
    {
        public event ChangedHandler ChangeName;
        public event ChangedHandler ChangeAge;
       string name = string.Empty;
        public virtual string Name
        {
            get { return name; }
            set
            {
                base.OnChanged(this, value, Name, ChangeName);
                name = value;
                OnPropertyChanged("Name");
            }
        }
        int age = 10;
        public virtual int Age
        {
            get { return age; }
            set
            {
                base.OnChanged(this, value, Age, ChangeAge);
                age = value;
                OnPropertyChanged("Age");
            }
        }
    }
}

Form1 界面

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System;
using System.Collections.Generic;
using System.Text;
using System.ComponentModel;
namespace Demo
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        Man m = new Man();
        private void Form1_Load(object sender, EventArgs e)
        {
            m.ChangeName += new ChangedHandler(m_ChangeName);
            m.ChangeAge += new ChangedHandler(m_ChangeAge);
        }
        void m_ChangeAge(object sender, object v)
        {
            SetText("m.Age " + v.ToString());
        }
        void m_ChangeName(object sender, object v)
        {
            SetText("m.Name " + v.ToString());
        }
        private void btnName_Click(object sender, System.EventArgs e)
        {
            m.Name = textBox2.Text;
        }
        public void SetText(string txt)
        {
            textBox1.Text += txt+ "\r\n";
        }
        private void btnAge_Click(object sender, System.EventArgs e)
        {
            m.Age = int.Parse(textBox3.Text);
        }
    }
}

https://blog.csdn.net/taoerit/article/details/54290623?utm_medium=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-1.channel_param&depth_1-utm_source=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-1.channel_param