js利用数组length属性清空和截短数组的小例子

1.使用length清空数组：

<script>
    var arr1 = ['aaa','bbbb','https://3water.com'];
    alert(arr1);
    arr1.length = 0;
    alert(arr1); //数组为空
</script>

2.使用length截短数组：

<script>
    var arr1 = ['aaa','bbbb','c','d','e'];
    arr1.length = 3;
    alert(arr1); //截断数组aaa,bbbb,c
</script>