有没有更有效的方式组合这些对象？

Question

I am working on a project that involves creating 2 timers. The styles are different, however, the operations of both timers are very similar. I have created 2 different objects for this, but I was wondering if there is a more efficient way to refactor this and avoid repetition?

var timer1 = { 
  started: false, 
  minutes: 0,   
  seconds: 0, 
  interval: null,
  init: function() {
    var self = this;
    this.interval = setInterval(function() { 
      self.intervalCallback.apply(self); 
    }, 1000);
    // ...
}

var timer2 = { 
  timer2Started: false,
  timer2Minutes: 0, 
  timer2Seconds: 0,
  interval: null,
  init: function() { 
    var newTimer = this;
    this.interval = setInterval(function() { 
      self.intervalCallback.apply(newTimer); 
    }, 1000);
    // ...
}

$(document).ready(function() { 
  timer1.init(); 
  timer2.init(); 
});

Answer 1

You can use a single object and assign to 2 variables like this

var timer = { 
  started: false, 
  minutes: 0,   
  seconds: 0, 
  interval: null,
  init: function() {
    var self = this;
    this.interval = setInterval(function() { 
      self.intervalCallback.apply(self); 
    }, 1000);
    // ...
}

var timer1 = timer, timer2 = timer;

$(document).ready(function() { 
  timer1.init(); 
  timer2.init(); 
});

Hope this helps.

Answer 2

You could use the Object.assign function.

Your code should look like this:

var timer1 = { 
    started: false, 
    minutes: 0,   
    seconds: 0, 
    interval: null,
    init: function() {
        var self = this;
        this.interval = setInterval(function() { 
            self.intervalCallback.apply(self); 
        }, 1000);
        // ...
    }
};

var timer2 = Object.assign({}, timer1);  

In this way, timer1 and timer2 are 2 different objects. If you write just timer2 = timer1, timer1 and timer2 will reference to the same object (timer1).

That's because objects in the JavaScript are being copied by reference, not by value. The Object.assign function creates a new instance of the object.