padStart / padEnd

padStart / padEnd

// "문자열".padStart(길이)
// "문자열".padStart(길이, 문자열)

const str1 = "456";
const currentStr1 = str1.padStart(1, "0"); //456
const currentStr2 = str1.padStart(2, "0"); //456
const currentStr3 = str1.padStart(3, "0"); //456
const currentStr4 = str1.padStart(4, "0"); //0456 앞의 숫자 길이값
const currentStr5 = str1.padStart(5, "0"); //00456 
const currentStr6 = str1.padStart(6, "0"); //000456 
const currentStr7 = str1.padStart(6, "1"); //111456
const currentStr8 = str1.padStart(6, "12"); //121456
const currentStr9 = str1.padStart(6, "123"); //123456
const currentStr10 = str1.padStart(6, "1234"); //123456
const currentStr11 = str1.padStart(6); //   456 앞에 공백처리 됌.

const currentStr12 = str1.padEnd(1, "0"); //456
const currentStr13 = str1.padEnd(2, "0"); //456
const currentStr14 = str1.padEnd(3, "0"); //456
const currentStr15 = str1.padEnd(4, "0"); //4560
const currentStr16 = str1.padEnd(5, "0"); //45600
const currentStr17 = str1.padEnd(6, "0"); //456000
const currentStr18 = str1.padEnd(6, "1"); //456111
const currentStr19 = str1.padEnd(6, "12"); //456121
const currentStr20 = str1.padEnd(6, "123"); //456123
const currentStr21 = str1.padEnd(6, "1231"); //456123
const currentStr22 = str1.padEnd(6); //456   뒤에 공백처리 됌.