Nodejs - visual studio code

■변수선언 : var, const, let

var a;
console.log(a);	//undefined

var b = 10;
console.log(b);	//10

const 는 상수

 

■함수선언 : 함수선언식, 함수표현식

  함수선언식

function sayHello() {
    console.log("Hello");
};

sayHello(); //Hello

  함수표현식

var SayHelloJs = function() {
    console.log("Hello Js");
};

SayHelloJs();   //Hello Js

 

■객체만들기

■속성만들기

let relationship = {
    name: 'zero',
    friends: ['nero', 'hero', 'xero'],
    logFriends: function() {
        let that = this;    //relationship을 가리키는 this
        //this.friends.forEach(function(friend){});
        this.friends.forEach((friend)=>{
            console.log(this.name, friend);
        });
    }
};

relationship.logFriends();

 

■this

console.log(this);  //{}
var a = 10;
console.log(this.a);//undefined
console.log(a);     //10