소문자/대문자/공백

trim () / trimStar() / trimEnd()

앞 뒤 공백을 제거 한다.(회원가입할 때 많이 사용한다.)

const str1 = "   javascript    "
const currentStr1 = str1.trim();

document.querySelector(".sample03_N1").innerHTML = "1";
document.querySelector(".sample03_Q1").innerHTML = str1;
document.querySelector(".sample03_M1").innerHTML = "trim()";
document.querySelector(".sample03_P1").innerHTML = currentStr1;

const str2 = "   javascript    ";
const currentStr2 = str2.trimStart();

document.querySelector(".sample03_N2").innerHTML = "2";
document.querySelector(".sample03_Q2").innerHTML = str2;
document.querySelector(".sample03_M2").innerHTML = "trimStart()";
document.querySelector(".sample03_P2").innerHTML = currentStr2;

const str3 = "   javascript    ";
const currentStr3 = str3.trimEnd();

document.querySelector(".sample03_N3").innerHTML = "3";
document.querySelector(".sample03_Q3").innerHTML = str3;
document.querySelector(".sample03_M3").innerHTML = "trimEnd()";
document.querySelector(".sample03_P3").innerHTML = currentStr3;

번호	기본값	메서드	리턴값
1	javascript	trim()	javascript
2	javascript	trimStart()	javascript
3	javascript	trimEnd()	javascript