Object

JavaScript Object; ( ) Object.prototype, (.. ). , Object.prototype, - , null, null.

Object.prototype , , , . , . , Object.prototype - JavaScript, - Object.prototype null .

Object

Object.prototype , , ( , - ). , Object.prototype, , . , null-. JavaScript :

• valueOf(), toString() toLocaleString() , , , . valueOf() toString() , .
• __defineGetter__(), __defineSetter__(), __lookupGetter__() __lookupSetter__() . Object.defineProperty() Object.getOwnPropertyDescriptor().
• __proto__ . Object.getPrototypeOf() Object.setPrototypeOf().
• propertyIsEnumerable() hasOwnProperty() Object.getOwnPropertyDescriptor() Object.hasOwn(), .
• isPrototypeOf() instanceof prototype .

, Object.prototype, call() , , .

const obj = {
  foo: 1,
  //        ,
  //       , 
  //      
  propertyIsEnumerable() {
    return false;
  },
};

obj.propertyIsEnumerable("foo"); // false;  
Object.prototype.propertyIsEnumerable.call(obj, "foo"); // true;  

//    
{ [ nameValuePair1[, nameValuePair2[, ...nameValuePairN] ] ] }

//    
new Object([value])

nameValuePair1, nameValuePair2, ... nameValuePairN

() ( ), .

value

.

Object

Object.length

1.

Object

Object.

Object

Object.assign()

.

Object.create()

.

Object.defineProperty()

, .

Object.defineProperties()

, .

Object.freeze()

: .

Object.getOwnPropertyDescriptor()

.

Object.getOwnPropertyNames()

, .

Object.getOwnPropertySymbols()

, .

Object.getPrototypeOf()

.

Object.is()

, ( , )

Object.isExtensible()

, .

Object.isFrozen()

, .

Object.isSealed()

, (sealed).

Object.keys()

, .

Object.observe()

.

Object.preventExtensions()

.

Object.seal()

.

Object.setPrototypeOf()

(.. [[Prototype]])

Object

JavaScript Object; Object, . , constructor toString(). Object , , , .

Object()

.

Object.prototype.constructor

, .

Object.prototype.__proto__

, .

Object.prototype.__defineGetter__()

, .

Object.prototype.__defineSetter__()

, , .

Object.prototype.__lookupGetter__()

, .

Object.prototype.__lookupSetter__()

, .

Object.prototype.hasOwnProperty()

, , , .

Object.prototype.isPrototypeOf()

, , , , .

Object.prototype.propertyIsEnumerable()

, , enumerable own.

Object.prototype.toLocaleString()

toString().

Object.prototype.toString()

.

Object.prototype.valueOf()

.

: Object undefined null

Object o:

const o = new Object();
const o = new Object(undefined);
const o = new Object(null);

: Object Boolean

Boolean o:

//  o = new Boolean(true);
const o = new Object(true);

//  o = new Boolean(false);
const o = new Object(Boolean());