JavaScript长度属性 (JavaScript length property)
length property is used to get and set the length of an array in JavaScript.
length属性用于获取和设置JavaScript中数组的长度。
Syntax to get the length of an array:
获取数组长度的语法：
array_name.length;
Syntax to set the length of an array:
设置数组长度的语法：
array_name.length = value;
//Here, value is the total number elements
//(length) to set to an array.
Examples:
例子：
Input:
var arr1 = [10, 20, 30, 40, 50];
Function call:
arr1.length;
Output:
5
JavaScript Code to get/set the length of an array
JavaScript代码获取/设置数组的长度
<html>
<head>
<title>JavaScipt Example</title>
</head>
<body>
<script>
var arr1 = [10, 20, 30, 40, 50];
var arr2 = ["Amit", "Ankur", "Akash"];
var arr3 = [];
//getting length
document.write("length of arr1: " + arr1.length + "<br>");
document.write("length of arr2: " + arr2.length + "<br>");
document.write("length of arr3: " + arr3.length + "<br>");
//setting a length
arr3.length = 10;
document.write("length of arr3: " + arr3.length + "<br>");
</script>
</body>
</html>
Output
输出量
length of arr1: 5
length of arr2: 3
length of arr3: 0
length of arr3: 10
翻译自: https://www.includehelp.com/code-snippets/array-length-property-with-example-in-javascript.aspx
![COGS182 [USACO Jan07] 均衡队形[RMQ]](http://pic.xiahunao.cn/COGS182 [USACO Jan07] 均衡队形[RMQ])
)
