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    <script type="text/javascript">
        const _createArray = (number) => {
            // 补全代码
            //方法1
            //实例化数组对象，得到number个空值数组
            /*let arr = new Array(number);
            //填充数组里面的空值，将每个空值赋值为number
            let newArr = arr.fill(number);
            //返回新得到的数组newArr
            return newArr;*/
            //方法2
            //() => number 将数组中每个值赋值为number
            //Array.from({length: 4}, () => 4);
            //Array(4) [ 4, 4, 4, 4 ]
            //{length: number} 表明一个数组
            //Array.from(数组对象,回调函数) 
            //遍历每个数组元素，每个元素调用函数
            return Array.from({length: number}, () => number);
        }
    </script>
</body>

</html>