通过 INotifyPropertyChanged 实现观察者模式（转）

using System;

using System.Collections.Generic;

using System.Text;

using System.ComponentModel;



namespace Demo

{

    class Program

    {

        public static void Main(string[] args)

        {

            // 创建实例

            DemoCustomer demoCustomer = DemoCustomer.CreateNewCustomer();



            // 实现事件触发需要处理的事情

            demoCustomer.PropertyChanged += new PropertyChangedEventHandler(demoCustomer_PropertyChanged);



            // 更新值 引发事件

            demoCustomer.PhoneNumber = "100";



            // 等待

            Console.ReadLine();

        }



        static void demoCustomer_PropertyChanged(object sender, PropertyChangedEventArgs e)

        {

            // 获取被更改的属性名

            Console.WriteLine(e.PropertyName);



            // 获取最新更新的值

            Console.WriteLine(((DemoCustomer)sender).PhoneNumber);

        }

    }



    // 实现 INotifyPropertyChanged 接口 进行监听

    public class DemoCustomer : INotifyPropertyChanged

    {

        // 默认的私有属性

        private Guid idValue = Guid.NewGuid();

        private string customerName = String.Empty;

        private string companyNameValue = String.Empty;

        private string phoneNumberValue = String.Empty;



        /// <summary>

        /// 在更改属性时引发的事件。（这个事件将被外露。）

        /// </summary>

        public event PropertyChangedEventHandler PropertyChanged;

        private void NotifyPropertyChanged(String info)

        {

            if (PropertyChanged != null)

            {

                PropertyChanged(this, new PropertyChangedEventArgs(info));

            }

        }



        // 默认的构造

        private DemoCustomer()

        {

            customerName = "no data";

            companyNameValue = "no data";

            phoneNumberValue = "no data";

        }



        // 简单的工厂模式

        public static DemoCustomer CreateNewCustomer()

        {

            return new DemoCustomer();

        }



        public Guid ID

        {

            get

            {

                return this.idValue;

            }

        }



        public string CompanyName

        {

            get

            {

                return this.companyNameValue;

            }

            set

            {

                if (value != this.companyNameValue)

                {

                    this.companyNameValue = value;



                    // 当发生改变时，那么就触发事件，传入触发的属性名

                    NotifyPropertyChanged("CompanyName");

                }

            }

        }



        public string PhoneNumber

        {

            get

            {

                return this.phoneNumberValue;

            }

            set

            {

                if (value != this.phoneNumberValue)

                {

                    this.phoneNumberValue = value;



                    // 当发生改变时，那么就触发事件，传入触发的属性名

                    NotifyPropertyChanged("PhoneNumber");

                }

            }

        }

    }

}

转自：http://www.cnblogs.com/scarbean/archive/2010/11/05/1870056.html