Remoting asynchronous callbacks to broadcast messages to online users

Purpose of this article: to broadcast messages to the remoting online client.

The main techniques used: Async, Callback, broadcast.

Implementation process:

Defining a remote instance

usingSystem;usingSystem.Collections.Generic;usingSystem.Text;usingSystem.Runtime.Remoting.Messaging;namespaceremoteobject{//defining delegates, displaying callback messages     Public Delegate voidShowcallbackmsg (stringSTR1,stringstr2); //remote instances generated by the client for the server to invoke callbacks     Public classOnlinecallback:marshalbyrefobject {//How the client implements the delegate         Publicshowcallbackmsg showmsg; //callback for service-side invocation         Public voidCallBack (stringSTR1,stringstr2) {            if(ShowMsg! =NULL) {Showmsg.invoke (str1, str2); }        }    }    //remote instances running on the server     Public classRemoteobject:marshalbyrefobject {//static variables record each client generates a remote instance for the callback         Public StaticList<onlinecallback> Listonline =NewList<onlinecallback>();  PublicRemoteObject () {}//to add a client-side build for the callback remote instance         Public voidAddonlinecallback (Onlinecallback xcallback) {listonline.add (xcallback); }        //with OneWay, asynchronous execution, the client issues the execution command, that is, no longer waiting for return, referred to the server callback processing[System.Runtime.Remoting.Messaging.OneWay] Public voidDoSomething (stringSTR1,stringSTR2,intisleep) {            //to see the effect, wait a long timeSystem.Threading.Thread.Sleep (Isleep); //perform callbacks on all registered online remote instances, broadcast messages            foreach(Onlinecallback Xcallbackinchlistonline)            {Xcallback.callback (str1, str2); }        }    }}

Service side:

usingSystem;usingSystem.Collections;usingSystem.Collections.Generic;usingSystem.ComponentModel;usingSystem.Data;usingSystem.Drawing;usingSystem.Text;usingSystem.Windows.Forms;usingSystem.Runtime.Remoting;usingSystem.Runtime.Remoting.Channels;usingSYSTEM.RUNTIME.REMOTING.CHANNELS.TCP;namespaceremoteserver{ Public Partial classForm1:form { PublicForm1 () {InitializeComponent ();        } TcpChannel Chan1; Private voidButton1_Click (Objectsender, EventArgs e) {            //Start the service side            Try{IDictionary tcpproperties=NewHashtable (); tcpproperties["name"] ="RemoteTest"; //Specify the service porttcpproperties["Port"] =int.                                            Parse (TextBox1.Text); Binaryclientformattersinkprovider Tcpclientsinkprovider=NewBinaryclientformattersinkprovider (); BinaryServerFormatterSinkProvider Tcpserversinkprovider=NewBinaryServerFormatterSinkProvider (); Tcpserversinkprovider.typefilterlevel=System.Runtime.Serialization.Formatters.TypeFilterLevel.Full; Chan1=NewTcpChannel (tcpproperties, Tcpclientsinkprovider, Tcpserversinkprovider);                ChannelServices.RegisterChannel (CHAN1); RemotingConfiguration.RegisterWellKnownServiceType (typeof(Remoteobject.remoteobject),"RemoteTest", Wellknownobjectmode.singleton); MessageBox.Show ("Start success!"); Button1. Enabled=false ; Button2. Enabled=true ; }            Catch(Exception ex) {MessageBox.Show (ex).            Message); }        }        //Stop service Side        Private voidButton2_Click (Objectsender, EventArgs e) {            Try            {                if(Chan1! =NULL) {Channelservices.unregisterchannel (chan1); }            }            Catch(Exception ex) {MessageBox.Show (ex).            Message); } button1. Enabled=true; Button2. Enabled=false; }    }}

Client

usingSystem;usingSystem.Collections.Generic;usingSystem.Collections;usingSystem.ComponentModel;usingSystem.Data;usingSystem.Drawing;usingSystem.Text;usingSystem.Windows.Forms;usingSystem.Runtime.Remoting;usingSystem.Runtime.Remoting.Channels;usingSystem.Runtime.Remoting.Services;usingSYSTEM.RUNTIME.REMOTING.CHANNELS.TCP;namespaceremoteclient{ Public Partial classForm1:form { PublicForm1 () {InitializeComponent (); } TcpChannel chan1=NULL; Remoteobject.remoteobject obj1=NULL; Private voidBtnconnect_click (Objectsender, EventArgs e) {            //connecting to the service side            Try{IDictionary tcpproperties=NewHashtable (); Binaryclientformattersinkprovider Tcpclientsinkprovider=NewBinaryclientformattersinkprovider (); BinaryServerFormatterSinkProvider Tcpserversinkprovider=NewBinaryServerFormatterSinkProvider (); Tcpserversinkprovider.typefilterlevel=System.Runtime.Serialization.Formatters.TypeFilterLevel.Full; //to prevent clients from having more than one network card IP, specify the use of IP that can communicate with the server                if(BtnBindIp.Text.Trim (). Length >0) tcpproperties["BindTo"] =Btnbindip.text; tcpproperties["Timeout"] =5; //This is critical, 0 means listening on all ports, is the necessary condition for receiving server callbackstcpproperties["Port"] =0; Chan1=NewTcpChannel (tcpproperties, Tcpclientsinkprovider, Tcpserversinkprovider); //registering a communication pipelineChannelServices.RegisterChannel (CHAN1); Obj1=(Remoteobject.remoteobject) Activator.GetObject (typeof(remoteobject.remoteobject),"tcp://"+ Txtsrvip.text +":"+ Txtsrvport.text +"/remotetest"); //to generate a client remote instance for a service-side callbackRemoteobject.onlinecallback Xcallback =NewRemoteobject.onlinecallback (); //to specify a method for receiving processing service-side callbacksXcallback.showmsg =Newremoteobject.showcallbackmsg (xcallback_showmsg); //invoking the server-side remote method Addonlinecallback, logging the client remote instanceobj1.                Addonlinecallback (Xcallback); Btnconnect.enabled=false; Btninvoke.enabled=true; }            Catch(Exception ex) {MessageBox.Show (ex).                Message); Btnconnect.enabled=true; Btninvoke.enabled=false; }        }        Private voidBtnbreak_click (Objectsender, EventArgs e) {            Try            {                //Disconnect ConnectionChannelservices.unregisterchannel (CHAN1); Obj1=NULL; }            Catch(Exception ex) {MessageBox.Show (ex).            Message); } btnconnect.enabled=true; Btnbreak.enabled=false; }        Private voidBtninvoke_click (Objectsender, EventArgs e) {            Try            {                              //call the remote method of the service-side RemoteObject (its method is oneway asynchronous mode)Obj1. DoSomething ("AAA","BBB", the); }            Catch(Exception ex) {MessageBox.Show (ex).            Message); }        }        //Methods for handling service-side callback messages        voidXcallback_showmsg (stringSTR1,stringstr2) {MessageBox.Show (str1+str2); }    }}

Remoting asynchronous callbacks to broadcast messages to online users