js_20 数组CRUD

2018-11-22  本文已影响0人  basicGeek

数组添加和删除

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
<script>

    var arr = ["关羽","张飞","刘备"];
    var arr2 = [1,2,3]
    // console.log(arr);
//    //在数组的最末尾添加元素(返回新数组的长度)
//    var aaa = arr.push("abc");
//    var aaa = arr.push("abc","def");
//    var aaa = arr.push(arr2);
//    console.log(aaa);
//    console.log(arr);
//
//    //在数组的最末尾删除一个元素(返回新被删除的元素)
//    aaa = arr.pop();
//    console.log(aaa);
//    console.log(arr);


    //unshift在数组的最前面添加元素
    // aaa = arr.unshift("abc");
    // console.log(aaa);
    // console.log(arr);
    //
    aaa = arr.shift();
    console.log(aaa);
    console.log(arr);

</script>
</body>
</html>

数组反转和排序


var arr = ["e","d","c","b","a"];
console.log(arr.reverse());
var arr2 = [7,6,15,4,13,2,1];
//    console.log(arr.sort());
console.log(arr2);
console.log(arr2.sort(function (a,b) {
        return b-a;
}));
array crud
上一篇下一篇

猜你喜欢

热点阅读