- CSS = adj.
- HTML = noun.
- JS = verb.
JavaScript
Values
- Literals : Fixed values
- Variables : Variable values
Operators
- *
- /
- +
- -
- = : assignment
Expressions
- a combination of values, variables, and operators
Keywords
- var : declares a variable
- let : declares a block variable
- const : declares a block constant
- if
- switch
- for
- return
- try
- Comments
- // oneLine
- /* multiLine */
this
| 호출 위치 | 지칭 객체 |
|---|---|
| in an object method | the “owner” of the object |
| alone | the global object |
| in a funciton | global object |
| in a function, in strict mode | undefied |
| in an event | the element that received the event |
Chrome의 console은 간단한 REPL 프로그램!
Read-Evaluate-Print-Loop의 과정을 통해 빠르게 JS 소스 코드를 실행함
innerHTML
- to access an HTML element
document.getElementById("id").innerHTML = "changed";
document.write()
- testing purpose only ```js <button type=”button” onclick=”document.write(“test”)”>Try it</button> //HTML 초기 load 이후 작동 시 기존 HTML 요소 전체 사라짐
```
window.alert()
- window(global scope object) is optional
console.log
- debugging purpose
aleart()경고창prompt()입력창에 input된 값 콘솔 출력parseInt("string")str을 num으로 변환 출력console.log()요청 값 콘솔 출력