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
