publish.cs

Csharp网络应用案例导航 Csharp网络应用案例导航

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using PublishSubscribe;
using Ticker;
/// usings for remoting
/// need to add the System.Runtime.Remoting reference
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;


namespace PublishSubscribe
{
	/// <summary>
	/// Main publish class that displays connection and subscription information
	/// It also controls the publishing of new information to subscribers which
	/// is controlled by a timer and has responsibility for the TCP channels that
	/// allow remote access to the publisher
	/// </summary>
	public class PublishService : System.Windows.Forms.Form
	{
		private System.Windows.Forms.Label label1;
		private System.Windows.Forms.Label label2;
		/// <summary>
		/// Required designer variable.
		/// </summary>
		private System.ComponentModel.Container components = null;
		private System.Windows.Forms.TextBox m_NumSubscriptions;
		private System.Windows.Forms.TextBox m_TimerCalls;

		/// <summary>
		///声明一个发布者实例
		///由于通道的模式为sington，该实例将为服务端和所有客户端共享的实例
		/// delcare a member of the publisher class
		/// </summary>
		private static Publisher NewPublisher;


		/// <summary>
		/// 声明一个计数器，用于定时发布消息给订阅者
		/// Set a timer to control the flow of the publications
		/// </summary>
		private Timer timer;

		/// <summary>
		/// 目前已经发布的次数
		/// The number of timer calls. Needs to be static as it is incremented in the timer function
		/// </summary>
		private int nTimerCalls = 0;

		/// <summary>
		/// 声明一个TCP通道
		/// The TCP Server Channel
		/// </summary>
		private TcpChannel Channel;

		/// <summary>
		/// 订阅者的数目
		/// The number of subscriptions
		/// </summary>
		private int nSubscriptions = 0;


		/// <summary>
		/// 计数器事件响应函数
		/// 用于定时发布消息给订阅者
		/// The timer event to generate publications
		/// </summary>
		/// <param name="PassedObject">The Object that created the Timer</param>
		/// <param name="TimerArgs">The Event Arguments that are passed to the Timer function</param>
		private void TimerEvent( object PassedObject, EventArgs TimerArgs )
		{
			nTimerCalls++;
			
			m_TimerCalls.Text = nTimerCalls.ToString();
			
			if( NewPublisher != null )
				NewPublisher.PublishNewEvents();

			m_NumSubscriptions.Text = ( ( object )NewPublisher.NumSubscriptions ).ToString();

		}

		public PublishService()
		{
			//
			//初始化窗口控件 
			//Required for Windows Form Designer support
			//
			InitializeComponent();

			//
			// TODO: Add any constructor code after InitializeComponent call
			//
			///创建一个计数器实例
			timer = new Timer();
			/// 设置计数器的事件响应函数
			/// 需要注意，该响应函数的参数必须包含一个对象和一个事件处理句柄
			

			timer.Tick += new EventHandler( TimerEvent );
			///设置计数间隔
			///set the interval
			timer.Interval = 5000;
			///开始计数 
			///start the timer
			timer.Start();

			
			///创建一个通道实例，该通道使用端口8090
			Channel = new TcpChannel( 8090 );
			///注册通道 
			///register the channel with the runtime
			ChannelServices.RegisterChannel( Channel );

			///配置通道属性，通道名称为“PublishSubscribe”
			///该通道传递的对象类型为Publisher,采用Singleton模式 
			///register the remote type and pass in a uri identifying string
			RemotingConfiguration.RegisterWellKnownServiceType( typeof( Publisher ), "PublishSubscribe", WellKnownObjectMode.Singleton );

		
			///获得一个对象实例 
			///get a remote instance to the singleton publisher object
			try
			{
				NewPublisher = ( Publisher )Activator.GetObject( typeof( Publisher ), "tcp://localhost:8090/PublishSubscribe" ); 
			}
			///无法获得则捕捉异常，异常情况有可能是：指定的url地址不可达或者指定获得的对象定义不对
			catch( NullReferenceException nullExp )
			{
				MessageBox.Show( "The url for the object is invalid " + nullExp.Message );
			}
			catch( RemotingException remExp )
			{
				MessageBox.Show( "The object type is not defined properly, it needs to be derived for a remoting class " + remExp.Message );
			}
		}

		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if (components != null) 
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		#region Windows Form Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			this.label1 = new System.Windows.Forms.Label();
			this.m_NumSubscriptions = new System.Windows.Forms.TextBox();
			this.label2 = new System.Windows.Forms.Label();
			this.m_TimerCalls = new System.Windows.Forms.TextBox();
			this.SuspendLayout();
			// 
			// label1
			// 
			this.label1.Location = new System.Drawing.Point(10, 9);
			this.label1.Name = "label1";
			this.label1.Size = new System.Drawing.Size(185, 19);
			this.label1.TabIndex = 0;
			this.label1.Text = "订阅者的数目";
			// 
			// m_NumSubscriptions
			// 
			this.m_NumSubscriptions.Location = new System.Drawing.Point(195, 9);
			this.m_NumSubscriptions.Name = "m_NumSubscriptions";
			this.m_NumSubscriptions.ReadOnly = true;
			this.m_NumSubscriptions.Size = new System.Drawing.Size(128, 21);
			this.m_NumSubscriptions.TabIndex = 1;
			this.m_NumSubscriptions.Text = "";
			// 
			// label2
			// 
			this.label2.Location = new System.Drawing.Point(10, 37);
			this.label2.Name = "label2";
			this.label2.Size = new System.Drawing.Size(128, 27);
			this.label2.TabIndex = 2;
			this.label2.Text = "发布次数";
			// 
			// m_TimerCalls
			// 
			this.m_TimerCalls.Location = new System.Drawing.Point(195, 37);
			this.m_TimerCalls.Name = "m_TimerCalls";
			this.m_TimerCalls.ReadOnly = true;
			this.m_TimerCalls.Size = new System.Drawing.Size(128, 21);
			this.m_TimerCalls.TabIndex = 3;
			this.m_TimerCalls.Text = "";
			// 
			// PublishService
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
			this.ClientSize = new System.Drawing.Size(614, 164);
			this.Controls.AddRange(new System.Windows.Forms.Control[] {
																		  this.m_TimerCalls,
																		  this.label2,
																		  this.m_NumSubscriptions,
																		  this.label1});
			this.MaximizeBox = false;
			this.Name = "PublishService";
			this.Text = "发布者";
			this.ResumeLayout(false);

		}
		#endregion

		/// <summary>
		/// The main entry point for the application.
		/// </summary>
		[STAThread]
		static void Main() 
		{
			Application.Run(new PublishService());
		}

		private void OnPublishData(object sender, System.EventArgs e)
		{
			NewPublisher.PublishNewEvents();
		}

		
	}
}