JavaScript数组的使用
@TOC
一、数组的创建
第一种:var 数组名 = new Array();创建一个空数组
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script>
var arr=new Array();
console.log(arr)//打印到浏览器控制台
</script>
</head>
<body>
</body>
</html>
第二种:var arr2 = new Array(10);创建一个定长为10的数组
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script>
var arr2 = new Array(10);
arr2[0]="h";
arr2[9]="l"
console.log(arr2)
</script>
</head>
<body>
</body>
</html>
第三种var arr3 = new Array(a,b,c);创建时直接指定元素值
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script>
var arr3 = new Array("hello","world","JavaScript",10,true)
console.log(arr3)
</script>
</head>
<body>
</body>
</html>
第四种var arr4 = ["hello","world","Flyme awei"];相当于第三种的简写
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script>
var arr4 = ["hello","world","Flyme awei"]
console.log(arr4)
</script>
</head>
<body>
</body>
</html>
二、数组的元素和长度
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script type="text/javascript">
var arr = [1,2,3,4,5];
console.log(arr);
console.log(arr[0]);
console.log(arr.length)
</script>
</head>
<body>
</body>
</html>
控制台
1.通过修改length属性来改变数组长度的。
2.通过索引改变数组长度。
