JavaScript長度屬性 (JavaScript length property)
length property is used to get and set the length of an array in JavaScript.
length屬性用于獲取和設置JavaScript中數組的長度。
Syntax to get the length of an array:
獲取數組長度的語法：
array_name.length;
Syntax to set the length of an array:
設置數組長度的語法：
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代碼獲取/設置數組的長度
<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
輸出量
length of arr1: 5
length of arr2: 3
length of arr3: 0
length of arr3: 10
翻譯自: https://www.includehelp.com/code-snippets/array-length-property-with-example-in-javascript.aspx
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