nodejs events模塊

var EventEmitter = require('events').EventEmitter;

var emitter = new EventEmitter();

console.log(emitter.getMaxListeners());
//設置可監聽事件的最大個數
emitter.setMaxListeners(11);

function work(who){
    console.log(who + ' go to work')
}

//監聽事件
emitter.on('do', work);
emitter.on('do', function(who) {
    console.log(who + ' wash clothers')
});

emitter.on('rest', function(who) {
    console.log(who + ' can have a rest');
})

//移除監聽事件
emitter.removeListener('do', work);

//觸發事件
emitter.emit('do', 'John');
emitter.emit('do', 'lily');
emitter.emit('rest', 'Tom');

//所有‘do’的監聽事件
console.log(emitter.listeners('do'))

//監聽事件的個數
console.log(emitter.listenerCount('do'));