1.使用length清空數組：
複製代碼代碼如下:
<script>
var arr1 = ['aaa','bbbb','//www.VeVB.COm'];
alert(arr1);
arr1.length = 0;
alert(arr1); //數組為空
</script>
2.使用length截短數組：
複製代碼代碼如下:
<script>
var arr1 = ['aaa','bbbb','c','d','e'];
arr1.length = 3;
alert(arr1); //截斷數組aaa,bbbb,c
</script>