websocket实现简单聊天程序

程序的流程图：

主要代码：

服务端 app.js

先加载所需要的通信模块：

var express = require('express');
var app = express();
var http = require('http').createServer(app);
var io = require('socket.io').listen(http);
var fs = require('fs');

创建用户列表和消息列表：

var person = [];
var history = [];

绑定并监听80端口：

app.get('/',function (req,res) {
    res.sendFile(__dirname + '/login.html');
});

http.listen(80,function () {
    console.log('listening on *:80');
});

客户端连接成功后，触发响应事件connection，完成要绑定的事件并实现客户端出发的事件：

io.sockets.on('connection',function (socket) {
    var user = '';

    socket.emit('history', history);
    io.sockets.emit('updatePerson', person); 

    socket.on('sendMsg', function (data) {
        var obj = {};
        obj.content = data;
        obj.time = now();
        obj.name = user;
        if (history.length === history_num) {
            history.shift();
        }
        history.push(obj);
        io.sockets.emit('news', obj);
    });

    socket.on('setUserName', function (data) {
        user = data;
        person.push(user);
        io.sockets.emit('loginsucess');
        io.sockets.emit('updatePerson', person);
        io.sockets.emit('news', {content: user + '进入房间', time: now(), name: '系统消息'});
    });

    socket.on('disconnect', function () {
        if (user !== '') {
            person.forEach(function (value, index) {
                if (value === user) {
                    person.splice(index, 1);
                }
            });
            io.sockets.emit('news', {content: user + '离开房间', time: now(), name: '系统消息'});
            io.sockets.emit('updatePerson', person);
        }
    });
});

客户端 index.js：

先初始化用户信息：

 $scope.data = [];     //消息队列  
 $scope.name = '';    //用户名
 $scope.content = '';  //用户输入的消息
 $scope.personlist = []; //用户队列

然后连接服务器端：

const  socket_url = 'http://localhost';
var socket = io.connect(socket_url);

连接成功后，对用户昵称输入的验证：

$scope.checkName = function () {
    if($scope.name!==''){
        if($scope.personlist.length!==0){
            if($scope.personlist.indexOf($scope.name)>-1) {
                document.getElementById("info").textContent = "该昵称已被占用，请重新输入";
            }
            else{
                socket.emit('setUserName', $scope.name);
            }
        }
        else{
            socket.emit('setUserName', $scope.name);
        }
    }
    else{
        document.getElementById('name').focus();
    }
};

验证成功后，对用户输入消息要触发的事件：

$scope.sendMsg = function(data){
    var date = new Date();
    data = $scope.content;
    if($scope.content !== ''){
        socket.emit('sendMsg',data);
    }
    $scope.content = '';
};