JavaScript访问对象的未知属性

Question

Situation:

I have multiple JS-Objects with the same structure.

In all of those Objects there's a property called console.

I'd like to assign a value (the same value) to each of these properties.

Please find below the structure of my code:

NameOfMyObject = function() {

     return {

        actions: null,

        console: null,

        init: function() {}, 

        //object specific functions

    }
};

My Problem:

Currently I'm assigning the value manual, but I want do do it generic.

Code snippet

this.console = console;
this.actions.console = console;
this.fixtures.console = console;

How can I access the properties of my objects?

I hope I asked my question clear enough.

Answer 1

Here is how you would share a property across objects:

 function MyClass() {}; MyClass.prototype.console = {}; // Define a "common" property on the prototype var obj1 = new MyClass(); // Create two instances var obj2 = new MyClass(); Object.getPrototypeOf(obj1).console.id = 13; // Assign a value once... console.log(obj1.console.id); // ... and it exists on both instances console.log(obj2.console.id); 

The shared property is on the prototype object.

Instead of Object.getPrototypeOf(obj1) you can of course use MyClass.prototype , since you know that obj1 was created by MyClass . They give the same prototype object.

If your property always has an object as value and you don't need to replace that value, only mutate it by setting properties on that object, then you don't need to explicitly reference the prototype to set a new value.

So this works:

 function MyClass() {}; MyClass.prototype.console = {}; // Define a "common" property on the prototype var obj1 = new MyClass(); // Create two instances var obj2 = new MyClass(); obj1.console.id = 13; // Assign a value once... (getting console from the prototype) console.log(obj1.console.id); // ... and it exists on both instances console.log(obj2.console.id); 

But if you change console itself, you'll be setting it on the instance, not on the prototype:

 function MyClass() {}; MyClass.prototype.console = {}; // Define a "common" property on the prototype var obj1 = new MyClass(); // Create two instances var obj2 = new MyClass(); obj1.console = { id: 13}; // Setting an instance property now console.log(obj1.console.id); // ... and it does not exist on both instances console.log(obj2.console.id); // == undefined 

So if that kind of assignment should still work on the prototype, you need to use the first code block with Object.getPrototypeOf or MyClass.prototype .