Node.js的EventEmitter錯誤

Question

我當試圖繼承EvenEmitter

/* Consumer.js */ 
var EventEmitter = require('events').EventEmitter; 
var util = require('util'); 

var Consumer = function() {}; 

Consumer.prototype = { 
    // ... functions ... 
    findById: function(id) { 
    this.emit('done', this); 
    } 
}; 

util.inherits(Consumer, EventEmitter); 
module.exports = Consumer; 

/* index.js */ 
var consumer = new Consumer(); 
consumer.on('done', function(result) { 
    console.log(result); 
}).findById("50ac3d1281abba5454000001"); 

/* ERROR CODE */ 
{"code":"InternalError","message":"Object [object Object] has no method 'findById'"} 

我已經試過幾乎所有的東西，仍然不工作

Answer 1

幾件事情有一個錯誤。您正在覆蓋原型而不是擴展原型。另外，在添加新方法之前移動util.inherits（）調用：

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

var Consumer = function Consumer() {} 

util.inherits(Consumer, EventEmitter); 

Consumer.prototype.findById = function(id) { 
    this.emit('done', this); 
    console.log('found'); 
}; 

var c = new Consumer(); 
c.on('done', function(result) { 
    console.log(result); 
}); 

c.findById("50ac3d1281abba5454000001");