[Java script] array_push_pop

array_push_pop.html

0.00MB

 <script>

        arr = new Array();

        arr = [];

 

        arr =[,,,,];

        console.log(arr);

        arr = [1,2,3]; //[1,2,3];

 

        //Array push()

        arr.push(3)  //배열에 push넣으면 뒤에 추가적으로 하나가 더 붙음  [1,2,3,3]

        arr.push(4)  //[1,2,3,3,4]

        

        arr.push(5) // [1,2,3,3,4,5]

        console.log(arr); 

 

        //Array push의 반대, 항상 맨 마지막 값이 제거됨

        arr.pop(); //[1,2,3,3,4]

        console.log(arr);

        arr.pop();

        arr.pop(); //[1,2,3] 이것은 pop()을 사용하게되면 바로 결과물을 만들어 줌

 

        arr.push(4);

        arr.push(5);

        arr.push(6);

        arr.push(7);

        arr.push(8);

        arr.push(9);

        arr.push(10);

        console.log(arr);

        // key [1,2,3,4,5,6,7,8,9,10]

        //value [0,1,2,3,4,5,6,7,8,9,10]

        console.log(arr.indexOf(4,0)) //1: 찾을 요소 2: 어디서부터 찾을지 

        console.log(arr.indexOf(4,4)) //-1 찾을 수 없다. 

        console.log(arr.indexOf(4,2)); 3

 

        

        arr.indexof()  //요즘 많이 안씀 위치값 찾는 것 indexof 인자값이 2개 들어감

        arr.indexof() // 1: 찾을 요수 2: 어디서부터 찾을지

 

    </script>