WinForm窗体之间参数传递(委托加事件观察者模式实现)

MiddleModule：

using System;
using System.Collections.Generic;
using System.Text;

namespace Observer
{
    /// <summary>
    /// 定义发布消息的委托
    /// </summary>
    /// <param name="sender">发布者</param>
    /// <param name="msg">消息</param>
    public delegate void Send(object sender, object msg);
    /// <summary>
    /// 观察者的中间模块组建
    /// </summary>
    public class MiddleModule
    {
        /// <summary>
        ///消息发布的事件
        /// </summary>
        public static event Send eventSend;

        public static void SendMessage(object sender, object msg)
        {
            if (eventSend != null)
            {
                eventSend(sender, msg);
            }
        }
    }
}

namespace WinObserver
{
    public partial class FrmMain : Form
    {
        /// <summary>
        /// 构造方法，在构造主窗体的时候就订阅来自FrmChild1的消息
        /// </summary>
        public FrmMain()
        {
            InitializeComponent();
            MiddleModule.eventSend += new Send(MiddleModule_eventSend);
        }

        /// <summary>
        /// 接收FrmChild1的回传数据
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="msg"></param>
        void MiddleModule_eventSend(object sender, object msg)
        {
            FrmChild1 frmChild1 = sender as FrmChild1;
            if (null != frmChild1)
            {
                this.lblMsg.Text = "FrmChild1的回传数据："+msg.ToString();
            }
        }

        private void btnShow1_Click(object sender, EventArgs e)
        {
            FrmChild1 frmChild1 = FrmChild1.CreateInstance();
            frmChild1.Show();
        }

        private void btnShow2_Click(object sender, EventArgs e)
        {
            FrmChild2 frmChild2 = FrmChild2.CreateInstance();
            frmChild2.Show();
        }

        private void btnSend_Click(object sender, EventArgs e)
        {
            //由Observer模块传递数据
            if (String.IsNullOrEmpty(this.txtMsg.Text))
            {
                MiddleModule.SendMessage(this, String.Empty);
            }
            else
            {
                MiddleModule.SendMessage(this, this.txtMsg.Text);
            }
        }
    }
}

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 Observer;

namespace WinObserver
{
    public partial class FrmChild1 : Form
    {
        private static FrmChild1 frmChild1 = null;

        private FrmChild1()
        {
            InitializeComponent();
            MiddleModule.eventSend += new Send(MiddleModule_eventSend);
        }
            
        void MiddleModule_eventSend(object sender, object msg)
        {
            FrmMain frmMain = sender as FrmMain;
            if (null != frmMain)
            {
                this.lblMsg.Text = msg.ToString();
            }
        }

        public static FrmChild1 CreateInstance()
        {
            if (null == frmChild1)
            {
                frmChild1 = new FrmChild1();
            }
            return frmChild1;
        }

        private void btnSendBack_Click(object sender, EventArgs e)
        {
            //由Observer模块传递数据
            if (String.IsNullOrEmpty(this.txtMsg.Text))
            {
                MiddleModule.SendMessage(this, String.Empty);
            }
            else
            {
                MiddleModule.SendMessage(this, this.txtMsg.Text);
            }
        }
    }
}

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 Observer;

namespace WinObserver
{
    public partial class FrmChild2 : Form
    {
        private static FrmChild2 frmChild2 = null;

        /// <summary>
        /// 接收来自FrmMain传递过来的数据
        /// </summary>
        private FrmChild2()
        {
            InitializeComponent();
            MiddleModule.eventSend += new Send(MiddleModule_eventSend);
        }

        void MiddleModule_eventSend(object sender, object msg)
        {
            FrmMain frmMain = sender as FrmMain;
            if (null != frmMain)
            {
                this.lblMsg.Text = msg.ToString();
            }
        }

        public static FrmChild2 CreateInstance()
        {
            if (null == frmChild2)
            {
                frmChild2 = new FrmChild2();
            }
            return frmChild2;
        }
    }
}