29. slice()
"배열".slice(시작위치, [끝나는 위치])
- 시작 위치에서 종료 위치 값을 추출하여 새로운 배열을 반환합니다.
{
['j','a','v','a','s','c','r','i','p','t']; //['j','a','v','a','s','c','r','i','p','t']
['j','a','v','a','s','c','r','i','p','t'].slice(1); //['a','v','a','s','c','r','i','p','t']
['j','a','v','a','s','c','r','i','p','t'].slice(2); //['v','a','s','c','r','i','p','t']
['j','a','v','a','s','c','r','i','p','t'].slice(0, 1); //['j']
['j','a','v','a','s','c','r','i','p','t'].slice(1, 2); //['a']
['j','a','v','a','s','c','r','i','p','t'].slice(0, 2); //['j','a']
['j','a','v','a','s','c','r','i','p','t'].slice(0, 3); //['j','a','v']
['j','a','v','a','s','c','r','i','p','t'].slice(5, 10); //['c','r','i','p','t']
['j','a','v','a','s','c','r','i','p','t'].slice(5, -1); //['c','r','i','p']
['j','a','v','a','s','c','r','i','p','t'].slice(5, -2); //['c','r','i']
['j','a','v','a','s','c','r','i','p','t'].slice(-1); //['t']
['j','a','v','a','s','c','r','i','p','t'].slice(-2); //['p','t']
['j','a','v','a','s','c','r','i','p','t'].slice(-3); //['i','p','t']
['j','a','v','a','s','c','r','i','p','t'].slice(-3, -1); //['i','p']
['j','a','v','a','s','c','r','i','p','t'].slice(-3, -2); //['i']
}
30. splice()
"배열".slice(시작위치, [삭제 갯수], [요소])
- 배열의 기존 요소를 삭제 또는 교체하거나 새 요소를 추가하여 배열의 내용을 변경합니다.
{
const arrNum1 = [100, 200, 300, 400, 500];
const result1 = arrNum1.splice(1);
console.log(result1); //[200, 300, 400, 500]
console.log(arrNum1); //[100]
const arrNum2 = [100, 200, 300, 400, 500];
const result2 = arrNum2.splice(1, 2);
console.log(result2); //[200, 300]
console.log(arrNum2); //[100, 400, 500]
const arrNum3 = [100, 200, 300, 400, 500];
const result3 = arrNum3.splice(1, 4);
console.log(result3); //[200, 300, 400, 500]
console.log(arrNum3); //[100]
const arrNum4 = [100, 200, 300, 400, 500];
const result4 = arrNum4.splice(1, 2, "javascript");
console.log(result4); //[200, 300]
console.log(arrNum4); //[100, "javascript", 400, 500]
const arrNum5 = [100, 200, 300, 400, 500];
const result5 = arrNum5.splice(1, 0, "javascript");
console.log(result5); //[]
console.log(arrNum5); //[100, "javascript", 200, 300, 400, 500]
const arrNum6 = [100, 200, 300, 400, 500];
const result6 = arrNum6.splice(0, 4, "javascript");
console.log(result6); //[100, 200, 300, 400]
console.log(arrNum6); //["javascript", 500]
const arrNum7 = [100, 200, 300, 400, 500];
const result7 = arrNum7.splice(2, 2, "javascript", "react");
console.log(result7); //[300, 400]
console.log(arrNum7); //[100, 200, "javascript", "react", 500]
const arrNum8 = [100, 200, 300, 400, 500];
const result8 = arrNum8.splice(-2, 2, "javascript");
console.log(result8); //[400, 500]
console.log(arrNum8); //[100, 200, 300, "javascript"]
//result는 삭제된 요소
//arrNum은 나머지 + 추가된 요소
}