Create Object 20170223 AM

1. Factory mode

Encapsulated with functions.

function Creatperson (name,age,job) {

var 0 = new Object ();

O.name = name;

O.age = age;

O.job = job;

O.sayname = function () {

alert (this.name);

};

return o;

}

var person1 = Creatperson ("TFS", 5, "singer");

var person2 = Creatperson ("TFR", 6, "Painter");

Advantage: The person object was created and can be called countless times.

Disadvantage: Cannot know the type of object.

2, the constructor function pattern.

function Person (name,age,job) {

THIS.name = name;

This.age = age;

This.job = job;

This.sayname = Sayname;

};

function Sayname () {
alert (this.name);

};

var person1 =new person ("TFS", 5, "singer");

var person2 =new person ("TFR", 6, "Painter");

Detection Object type: instanceof

Disadvantage: Each member cannot be reused.

3, prototype mode.

Prototype

[[prototype]]

Constructor: Each time a function is created, its prototype object is created, and the object automatically obtains the constructor attribute.

hasOwnProperty (): the instance defines this property to return true.

such as: Var person1 =new person ();

Person1.name = "TFS";

Alert (Person1.hasownproperty ("name"));//true

In: Object can access the given property and return true, regardless of whether the property is in the instance or in the prototype.  Alert ("name" in Person1); True

For-in loop: Returns enumerable properties that are accessible to all objects.

Hasprototypeproperty (): property returns True in the prototype. Alert (Hasprototypeproperty (person, "name"));

Object.keys (): Gets all enumerable instance properties.  var keys = Object.keys (Person.prototype);  alert (keys); "Name"

Object.getownpropertynames (): All instance properties can be obtained, whether or not enumerated.

The dynamics of a prototype:

function person () {}

var friend = new person ();

Person.prototype = {

Constructor:person; Creates a new object in literal form and no longer points to person if constructor is not specified.

Name: "TFS";

Age:5;

}

alert (friend.name); Error

Prototype Object disadvantage: All instances share an array.

function person () {}

Person.prototype = {

Constructor:person;

Name: "TFS";

Age:5;

friends:["1", "2"];

};

var person1 = new Person ();

var person2 = new Person ();

Person1.friends.push ("3");

alert (person1.friends); "1,2,3"

alert (person2.friends); "1,2,3". All instances are found to share an array.

4. Construction function + prototype mode

function Person (name,age,job) {

THIS.name = name;

This.age = age;

This.job = job;

This.friends =["1", "2"];

};

Person.prototype ={

Constructor:person;

Sayname:function () {

alert (this.name);

}

}

var person1 = new Person ();

var person2 = new Person ();

Person1.friends.push ("3");

alert (person1.friends); "1,2,3"

alert (person2.friends); "1,2"

alert (person1.sayname===person2.sayname); True

5. Dynamic prototype mode

function Person (name,age,job) {

THIS.name = name;

This.age = age;

This.job = job; if (typeof this.sayname!= "function") {//Only add it to the prototype if the Sayname () method does not exist.

Person.propotype.sayName = function () {

alert (this.name);

}

}

var person =new person ("TFS", 5, "singer");

Person.sayname ();

6. Parasitic structural function pattern

7, the Safe construction function pattern