Question

I have a object like this:

myobj={
  //where to define Car car=new Car();
  test:{
    testFunc1(){car.paintTest();},
    testFunc2(){car.drawTest();}
  },

  use:{
    useFunc1(){car.paintUse();},
    useFunc2(){car.drawUse();}
  },
};

I will use myobj in the way that, in another js file, I can easily call

myobj.test.testFunc2();

or

myobj.use.useFunc1();

As you notice, in myobj, I have a car instance frequently be used in different functions in different sub-objects (e.g. “test”, “use” sub-objects).

I am wondering, where can I define Car car=new Car(); in myobj so that the car is defined once and can be used in several functions in myobj.

Answer 1

you can do that like this:

myobj={
  car: new Car(),

  test: {
    var self = this;
    testFunc1(){self.car.paintTest();},
    testFunc2(){self.car.drawTest();}
  },

  use: {
    var self = this;
    useFunc1(){self.car.paintUse();},
    useFunc2(){self.car.drawUse();}
  },
};

UPDATE

working version with fake Car object:

function Car (){
    this.paintTest = function(){console.log('painttest')}
    this.drawTest = function(){console.log('drawtest')}
    this.paintUse = function(){console.log('paintuse')}
    this.drawUse = function(){console.log('drawuse')}
}

myobj = {
  car: new Car(),

  test:{
      testFunc1: function() {myobj.car.paintTest();},
      testFunc2: function() {myobj.car.drawTest();}
  },

  use: {
      useFunc1: function(){myobj.car.paintUse();},
      useFunc2: function(){myobj.car.drawUse();}
  },
};

myobj.test.testFunc1();
myobj.test.testFunc2();
myobj.use.useFunc1();
myobj.use.useFunc2();

fiddle: http://jsfiddle.net/maniator/KcQvL/