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Is there any other way to look up for the prototype properties of an javascript object. Lets say I have like this.
function proton() { this.property1 = undefined; this.property2 = undefined; }; proton.prototype = { sample1 : function() { return 'something'; }, sample2 : function() { return 'something'; } }; var my_object = new proton(); console.log(Object.keys(my_object)); returns ["property1", "property2"]
console.log(Object.getOwnPropertyNames(my_object)); returns ["property1", "property2"]
But what i want to print is the prototype properties of the object my_object.
['sample1', 'sample2']
In order for me to see the prototype properties of that object i need to console.log(object) and from developer tools i can look up for the properties of that object.
But since I am using third party libraries like phaser.js, react.js, create.js so i don't know the list of the prototype properties of a created object from this libraries.
Is there any prototype function of Object to list down all the prototpye properties of a javascript object?
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To get all own properties of an object in JavaScript, you can use the Object. getOwnPropertyNames() method. This method returns an array containing all the names of the enumerable and non-enumerable own properties found directly on the object passed in as an argument.
Every object in JavaScript has a built-in property, which is called its prototype. The prototype is itself an object, so the prototype will have its own prototype, making what's called a prototype chain. The chain ends when we reach a prototype that has null for its own prototype.
prototype by default has one own property: constructor , which references the constructor function itself — that is, Box. prototype. constructor === Box .
Properties are the values associated with a JavaScript object. A JavaScript object is a collection of unordered properties. Properties can usually be changed, added, and deleted, but some are read only.
Not a prototype method, but you can use Object.getPrototypeOf to traverse the prototype chain and then get the own property names of each of those objects.
function logAllProperties(obj) { if (obj == null) return; // recursive approach console.log(Object.getOwnPropertyNames(obj)); logAllProperties(Object.getPrototypeOf(obj)); } logAllProperties(my_object); Using this, you can also write a function that returns you an array of all the property names:
function props(obj) { var p = []; for (; obj != null; obj = Object.getPrototypeOf(obj)) { var op = Object.getOwnPropertyNames(obj); for (var i=0; i<op.length; i++) if (p.indexOf(op[i]) == -1) p.push(op[i]); } return p; } console.log(props(my_object)); // ["property1", "property2", "sample1", "sample2", "constructor", "toString", "toLocaleString", "valueOf", "hasOwnProperty", "isPrototypeOf", "propertyIsEnumerable" If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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