When to use the constructor, the constructor with the new keyword

Js on when to use a constructor 
    generally have the same attributes create multiple objects / methods, will go write constructor will go new
     if only a single object, literals directly on the line 

var Person = { 
    name: 'postbird' , 
    address: 'Earth' , 
    the sayHello: function () {the console.log ( 'the Hello, the I AM' + the this .name);} 
};

js constructor creates objects add new questions 

/ * 
    new operators have done it: 
      1. Create a new object 
      2, the scope constructor assigns the new object (and therefore this points to the new object) 
      3, execution constructor code (added for the new object attribute) 
      4, returns a new object. 
* / 

Function the Obj (name) {
     the this .name = name;     
    the console.log ( the this ); // strict mode is a mode undefined nonstrict window object 
}
 var A = the Obj ( "name11"); // undefined 
A .name; // Uncaught TypeError: Can Not Read Property 'name' of undefined 
var B = new new the Obj ( 'name22');   // the Obj {name: "name22"} 
b.name; //name22 


// the new operator to create an object, and a constructor or no return value returned as basic data types, the object is returned 
function the Obj (name) {
     the this .name = name; 
} 
var B = new the Obj (); // {name obj: undefined} 

function obj (name) {
     the this .name = name;
     return 'Chic' ; 
} 
var B = new obj (); // obj {name: undefined} 

// create an object with the new operator, and constructor returns a reference type 
function Obj02 (name) {
     the this .name = name;
     return {}; 
}
var A02 = Obj02 ( "name11"); // Object {} 
a02.name; // undefined 
var B02 = new new Obj02 ( 'name22');   // Object {} 
b02.name; // undefined 

/ * * 
 * summarized : 
 * to be executed without new constructor, the return value is the result of the implementation of the constructor 
 * to add new keywords to the constructor in terms of execution, if the return is a basic data type, overlooked the return value, 
 * for the purposes of adding new keywords to the implementation of the constructor, if the return is a reference type, then returned to the reference type 
 * /


If you have a lot of object instances, inheritance or directed or mass participation constructor 

function the Person (name, address) {
     the this .name = name;
     the this .Address = address; 
} 
Person.prototype.sayHello = function () { 
    the console.log ( 'the I AM the Hi' + the this .name); 
} 

var P1 = new new the Person ( 'postbird', 'Earth' );
 var P2 = new new the Person ( 'ptbird', 'month The' ); 
In general, the constructor used widely, if simply objects, use literal enough. 

In the constructor object instantiation, inheritance and other applications, or more

When to use the constructor, the constructor with the new keyword

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