1 javascript可以通过setProperty()函数为对象添加属性。但是nodejs添加报错。TypeError: channel.setProperty is not a function
const events = require('events');
const net = require('net');
class Channel extends events.EventEmitter{
constructor(){
super();
this.clients = {};
this.subscriptions={};
}
}
const channel = new events.EventEmitter();
channel.setProperty('clients',{});
channel.setProperty('subscriptions',{});
channel.on('join',function abc(id,client){
console.log('this.constructor=',this.constructor);
this.clients[id] = client;
this.subscriptions[id] = (clientId,msg) => {
if(id != clientId){
this.clients[id].write(msg);
}
}
this.on('broadcast',this.subscriptions[id]);
})
net.createServer( client => {
const id = `${client.remoteAddress}:${client.remotePort}`;
channel.emit('join', id, client);
client.on('data',data => {
const msg = data.toString();
channel.emit('broadcast',id,msg);
})
}).listen(8888);
2 javascript可以通过prototype添加属性，但是nodejs报错。TypeError: Cannot set property 'clients' of undefined
const events = require('events');
const net = require('net');
class Channel extends events.EventEmitter{
constructor(){
super();
this.clients = {};
this.subscriptions={};
}
}
const channel = new events.EventEmitter();
channel.prototype.clients = {};
channel.prototype.subscriptions = {};
channel.on('join',function abc(id,client){
console.log('this.constructor=',this.constructor);
this.clients[id] = client;
this.subscriptions[id] = (clientId,msg) => {
if(id != clientId){
this.clients[id].write(msg);
}
}
this.on('broadcast',this.subscriptions[id]);
})
net.createServer( client => {
const id = `${client.remoteAddress}:${client.remotePort}`;
channel.emit('join', id, client);
client.on('data',data => {
const msg = data.toString();
channel.emit('broadcast',id,msg);
})
}).listen(8888);
3 直接针对对象添加属性，不报错
const events = require('events');
const net = require('net');
const channel = new events.EventEmitter();
channel.clients = {};
channel.subscriptions = {};
channel.name='zjz';
channel.on('join',function(id,client) {
console.log('this.name=',this.name);
})
net.createServer( client => {
const id = `${client.remoteAddress}:${client.remotePort}`;
channel.emit('join', id, client);
client.on('data',data => {
const msg = data.toString();
channel.emit('broadcast',id,msg);
})
}).listen(8888);//可以正常运行。