.net observer design pattern, different forms of traditional values, entrusted to implement the non-commissioned

1 What is the Observer design pattern

• Observer pattern is a software design pattern defines a relationship between the subject an-many, the coupling of the code can be reduced. As used herein, the observer model to achieve different forms of traditional values.

2. Observer design pattern to achieve non-commissioned

Figure ideas:

Use Interface
First create an interface file, IMessageON.cs, which has a RecieveMsg method;

  namespace WindowsFormsApplication2
{
    public interface IMessageON
    {
        void RecieveMsg(string str);
    }
}

In the Main window and open the main mediating role in all forms.
Code:

 namespace WindowsFormsApplication2
{
    public partial class Main : Form
    {
        public info_send info_send1 { get; set; } 
        public Main()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            info_send s1 = new info_send();
            this.info_send1 = s1;
            s1.Show();

            info_receive1 r1 = new info_receive1();
           // 用接口的形式注册 观察者。
            s1.MessageOnList.Add(r1);
            r1.Show();

            info_receive2 r2 = new info_receive2();
           // 用接口的形式注册 观察者。
            s1.MessageOnList.Add(r2);
            r2.Show();
        }

info_send form, create and transmit a data collection interface type
codes

 namespace WindowsFormsApplication2
{
    public partial class info_send : Form
    {
        public info_send()
        {
            InitializeComponent();
            MessageOnList = new List<IMessageON>(); //集合
          
        }
     
          //这个集合放我们的观察者
        public List<IMessageON> MessageOnList { get; set; }
        private void button1_Click(object sender, EventArgs e)
        {
            foreach (var messageOn in MessageOnList)
            {
            
                messageOn.RecieveMsg(textBox1.Text);
            }
        }
    }
}

info_receive1 forms, implement the interface, (info_receive2 the same form)

namespace WindowsFormsApplication2
{
    public partial class info_receive1 : Form,IMessageON //使用接口
    {
        public info_receive1()
        {
            InitializeComponent();
          
        }

        public void RecieveMsg(string str)  //实现接口
        {
            this.textBox1.Text = str;

        }

Renderings:

2. Observer design pattern commissioned achieve

There are also events using delegates
in the Main form mainly acts as an intermediary and open all the form, the code is as follows:

    namespace WindowsFormsApplication2
{
    public partial class Main : Form
    {
        public info_send info_send1 { get; set; }
        public Main()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            info_send s1 = new info_send();
            this.info_send1 = s1;
            s1.Show();

            info_receive1 r1 = new info_receive1();
            //事件的形式注册观察者。
            s1.Messevent+=r1.SetMsgTextEvent;
            //用户委托的形式注册观察者
            s1.Message += r1.SetMsgText;
            r1.Show();

            info_receive2 r2 = new info_receive2();
            //事件的形式注册观察者。
            s1.Messevent += r2.SetMsgTextEvent;
            //用户委托的形式注册观察者
            s1.Message += r2.SetMsgText;
            r2.Show();
        }
    }
 }

info_send form,

namespace WindowsFormsApplication2
{
    public partial class info_send : Form
    {
        public delegate void Mess(string str); //声明委托 

        public info_send()
        {
            InitializeComponent();  
        }
        
        #region 用户委托
        public Mess Message { get; set; }  //委托
        private void button1_Click(object sender, EventArgs e)
        {
            Message(textBox1.Text);
        } 
        #endregion

        #region 使用Event事件
        //事件
        public event Mess Messevent;
        private void button2_Click(object sender, EventArgs e)
        {
            Messevent(textBox1.Text);
        } 
        #endregion
    }
}

nfo_receive1 form, (info_receive2 the same form)

namespace WindowsFormsApplication2
{
    public partial class info_receive1 : Form
    {
        public info_receive1()
        {
            InitializeComponent();   
        }

        public void SetMsgTextEvent(string str)
        {
            this.textBox1.Text = " 事件委托" + str;
        }
        public void SetMsgText(string str)
        {
            this.textBox1.Text = " 用户委托" + str;
        }
    }
}

:( renderings as two effects)