How to use the ES6 object

This article introduces the knowledge of "how to use ES6 objects". In the operation of actual cases, many people will encounter such a dilemma, so let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

I. objects and properties and methods

Objects in JavaScript:

Var person= {name: "Jack", age:20}

Or:

Var name = "jack"; var age = 20 X var person = {name:name,age:age}; console.log (person.age); / / 20

The concise expression in ES6:

Let [name,age] = ["jack", 20]; let person = {name,age}; / / equivalent to person = {name: name,age: age} console.log (person.age); / / 20

Object methods in JavaScript:

Var person = {SayHi:function () {console.log ("hi");}} person.SayHi (); / / hi

It is succinctly stated in ES6:

Let person = {SayHi () {console.log ("hi");}} person.SayHi ()

ES6 allows expressions as attribute names, but be sure to put expressions in square brackets:

Var person = {["na" + "me"]: "jack", ["a" + "ge"]: 20}; console.log (person.age)

Or

Let str = "Hi"; let person = {["Say" + str] () {console.log ("hi");}} person.SayHi ()

Note: the concise representation of the attribute and the expression of the attribute name cannot be used at the same time, otherwise an error will be reported:

Let [name,age] = ["jack", 20]; let person = {["na" + "me"], ["a" + "ge"]}; / / error II, object extension operator.

Take out all traverable properties of the parameter object and copy them to the current object:

Let stu1 = {name: "Jack", age:20,sex: "male"}; let stu2 = {... stu1}; console.log (stu2); / / {name: "Jack", age:20,sex: "male"}

Merge two objects:

Let stu1BasicInfo = {name: "Jack", age:20,sex: "male"}; let stu1DetailInfo = {phone: "13524521457", mail: "ldh@163.com"}; let stu = {... stu1BasicInfo,...stu1DetailInfo}; console.log (stu); / / {name: "Jack", age:20,sex: "male", phone: "13524521457", mail: "ldh@163.com"}

Adding attributes is supported when copying objects:

Let stu1 = {name: "Jack", age:20,sex: "male"}; let stu2 = {... stu1,phone: "13554785452"}; console.log (stu2); / / {name: "Jack", age:20,sex: "male", phone: "13554785452"}

The added attribute is after the extension operator, take the added attribute:

Let stu1 = {name: "Jack", age:20,sex: "male"}; let stu2 = {... stu1,name: "rose", phone: "13554785452"}; console.log (stu2); / / {name: "rose", age:20,sex: "male", phone: "13554785452"}

Before the extension operation, the added attribute takes the content of the extension operator:

Let stu1 = {name: "Jack", age:20,sex: "male"}; let stu2 = {name: "rose", phone: "13554785452",... stu1}; console.log (stu2); / / {name: "Jack", phone: "13554785452", age:20,sex: "male"} "how to use ES6 objects", thank you for reading. If you want to know more about the industry, you can follow the website, the editor will output more high-quality practical articles for you!