Array对象：一个数组变量，就是一个数组对象
length属性：动态获取数组长度。如：var len = arrObj.length
join()
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>php.cn</title>
<script>
//将以下字符串转成数组， 然后再转成字符串
var str = "北京,上海,深圳,南京,合肥";
//转成数组
var arr=str.split(",");
//再转换成字符串
str = arr.join(",") ;
document.write("类型是："+typeof(str)+",字符串为："+str);
</script>
</head>
<body>
</body>
</html>
reverse()
功能：将数组中各元素颠倒顺序。
语法：arrObj.reverse()
参数：无
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>php.cn</title>
<script>
var arr=[1,2,3,4,5,6,7,8];
arr.reverse();
document.write(arr);
</script>
</head>
<body>
</body>
</html>
数组元素的删除和添加
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>php.cn</title>
<script>
//使用delete删除元素，查看长度是否改变
var arr=[1,2,3,4,5,6,7,8];
document.write("数组的长度为"+arr.length+",值为"+arr+"<br/>");
delete arr[0];
delete arr[1];
delete arr[2];
document.write("数组的长度为"+arr.length+",值为"+arr+"<br/>");
</script>
</head>
<body>
</body>
</html><!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>php.cn</title>
<script>
//使用delete删除元素，查看长度是否改变
var arr=[1,2,3,4,5,6,7,8];
document.write("数组的长度为"+arr.length+",值为"+arr+"<br/>");
arr.shift();
document.write("数组的长度为"+arr.length+",值为"+arr+"<br/>");
arr.pop();
document.write("数组的长度为"+arr.length+",值为"+arr+"<br/>");
</script>
</head>
<body>
</body>
</html>unshift()：往数组前面添加一个或多个数组元素，长度要改变。arrObj.unshift(“a” , “b” , “c”)
push()：往数组结尾添加一个或多个数组元素，长度要改变。arrObj.push(“a” , “b” , “c”)
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>php.cn</title>
<script>
//使用delete删除元素，查看长度是否改变
var arr=[1,2,3,4,5,6,7,8];
document.write("数组的长度为"+arr.length+",值为"+arr+"<br/>");
arr.unshift(0);
document.write("数组的长度为"+arr.length+",值为"+arr+"<br/>");
arr.push(9);
document.write("数组的长度为"+arr.length+",值为"+arr+"<br/>");
</script>
</head>
<body>
</body>
</html>下一节