오픈소스웹소프트웨어 Basics of JavaScript

Features of JavaScript

Interpreted language(by web browser)

=not compiled language

 

programming language for web

 

 

 

location of javascript

• external javascript(outside javascript)
• inner javascript
• inline javascript

 

extension==.js

 

 

onclick is event

 

 

innerHTML is a property

 

 

document.write is very similar to printf

 

 

window.alert(5+6);

you can write only alert(5+6);

 

 

 

 

 

javascript variables

var int a; X

var a;

 

 

 

reserved keywords를

눈으로 살펴보셨으면 좋겠습니다

 

 

 

comparision operator

시험에는 이런 키워드도 나올겁니다

abstract equlaliyy comparision

==

loose equality dulble equlas

compare the identity, but to similar type

 

check values, does not check data types

 

 

===

stric equality, triple equals

both type and value same

 

 

check both values and data types

 

10=="10" -> true

10 === "10" -> false

 

 

 

when adding a number and a string, javascript will treat the number as a string

 

 

 

 

var vs let

let

cannot be redeclared

should be initialized

block scope

 

var

can be redeclared

전역변수

 

 

 

 

parameter is parameter

argument is a value that sent to parameter

시험에 나온다 이 말이야

 

 

invoke==호출==call

 

 

 

f=parameter

77=argument

 

 

(function{})()

->automatically run itself