array/js0609_index_array.html

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    JavaScript_array_classnotes

    <script>
    let myArr = [1,2,3,4];
    let beautiful = ["lancome"," Ysl","Sk2","mac"];
    console.log(myArr);
    console.log('beautiful',beautiful);

    //for
    for (let i = 0; i < carsArr.length; i++) {
    // console.log(i);
    console.log(carsArr[i]);
    //Q key ? value ?
     // key => i
    // value => carsArr[i]
    }

    // function
    function myFun(value, key) {
        // js => arrow function 箭頭函式
        // function 簡化而來
    }

    //array裡有 foreach &　for of & for in
    //foreach
    carsArr.forEach((value, key, array) => {
        console.log('hello js foreach ');
        console.log(key);
        console.log(value);
        console.log(array);
        // e = v 
    });

    carsArr.forEach(element => {

    });

    //======================================
    // 自己練習
    // js index array
    //let myArr = [1, 3, 5, 7, 9];
    // 單一呼叫 array[key]
    //console.log(myArr[0]); // 1
    //console.log(myArr[1]); // 3
    //console.log(myArr[2]); // 5
    //console.log(myArr[3]); // 7

    //運算子符號
    // ==等於
    // != 不等於
    // if (value != "html") {
    //       newStudentArr.push(value);
    //    }
    //}

    </script>

  
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