JavaScript RegExp {x} 量词

2025年3月18日 | 阅读 5 分钟

JavaScript 的 "m{X}" 量词作用于任何由 (m) 组成的系列文本，重复 X 次。{X,} 表示一个数字，可以通过 JavaScript 中的量词函数匹配字符串 x 次。正则表达式量词在字符串中使用 regex search, match, test, 和 exec 方法进行操作。我们可以为量词中可用的字符使用 regex 修饰符。

语法

以下语法可用于正则表达式 "x" 量词以获取可用字符。

或

支持的浏览器

以下浏览器支持 JavaScript 正则表达式 {x} 量词。

谷歌浏览器
Internet Explorer
Opera
Safari
火狐
边

示例

以下示例展示了 JavaScript 正则表达式的 regex {x} 量词。我们可以使用数字或数字作为量词中的字符。

示例 1

给出的示例使用量词正则表达式匹配包含一位和两位数字序列号的 "java" 数据。我们可以获得字符串中字符的可用性。

<!DOCTYPE html>
<html>
<head>
<title>
JavaScript RegExp quantifier
</title>
<style>
#demo1{
background-color: orange;
border: 1px solid black;
width: 370px;
}
</style>
</head>
<body>
<div id = "demo1">
<h3>
JavaScript RegExp {x} quantifier
</h3>
<h4> The regex quantifier matches for a sequence of one and two digits:
</h4>
<div id = "regex_quant"> </div>
<div id = "regex_quant1"> </div>
<!-- click the button for the result -->
<button onclick = "display_group();"> Click Here! </button>
</div>
<script>
function display_group() {
//use single sequence quantifier with global modifier
var sequance_pattern1 = "java, PHP, jquery, javascript, node js";
let input_pattern = /\java{1}/g;
var quant_sequance1 = sequance_pattern1.match(input_pattern); 
var ele = document.getElementById("regex_quant");
ele.innerHTML = "Available Values for one digit sequence: "+quant_sequance1;
//use two sequence quantifier with global modifier
let input_pattern1 = /\j{2}/g;
var quant_sequance2 = sequance_pattern1.match(input_pattern1); 
var ele1 = document.getElementById("regex_quant1");
ele1.innerHTML = "Available Values for two digit sequence: "+quant_sequance2;
}
</script>
</body>
</html>

输出

该量词在 JavaScript 中给出了几次 "j" 值的可用性。

示例 2

给出的示例匹配包含两位和三位数字序列号的数字。我们可以获得字符串中字符的可用性。

<!DOCTYPE html>
<html>
<head>
<title>
JavaScript RegExp quantifier
</title>
<style>
#demo1{
background-color: orange;
border: 1px solid black;
width: 370px;
}
</style>
</head>
<body>
<div id = "demo1">
<h3>
JavaScript RegExp {x} quantifier
</h3>
<h4> The regex quantifier matches the exact sequence of two and three digits:
</h4>
<div id = "regex_quant"></div>
<div id = "regex_quant1"></div>
<!-- click the button for the result -->
<button onclick = "display_group();"> Click Here! </button>
</div>
<script>
function display_group() {
var sequance_pattern1 = "2, 0, 200, 2000, 100";
//use a digit sequence quantifier with a global modifier
let input_pattern = /\d{2}/g;
var quant_sequance1 = sequance_pattern1.match(input_pattern); 
var ele = document.getElementById("regex_quant");
ele.innerHTML = "Available Values for two digit sequence: "+quant_sequance1;
//use a three-digit sequence quantifier with a global modifier
let input_pattern1 = /\d{4}/g;
var quant_sequance2 = sequance_pattern1.match(input_pattern1); 
var ele1 = document.getElementById("regex_quant1");
ele1.innerHTML = "Available Values for three-digit sequence: "+quant_sequance2;
}
</script>
</body>
</html>

输出

该量词在 JavaScript 中给出了 "20" 值的可用性。

示例 3

给出的示例使用量词测试包含两位和五位数字序列号的数字。我们可以为字符串字符的可用性获得布尔输出。

<html>
<head>
<title>
JavaScript RegExp quantifier
</title>
<style>
#demo1{
background-color: orange;
border: 1px solid black;
width: 370px;
}
</style>
</head>
<body>
<div id = "demo1">
<h3>
JavaScript RegExp {x} quantifier
</h3>
<h4> The regex quantifier tests for a sequence of exact two and five digits:
</h4>
<div id = "regex_quant"></div>
<div id = "regex_quant1"></div>
<!-- click the button for the result -->
<button onclick = "display_group();"> Click Here! </button>
</div>
<script>
function display_group() {
//use regex with required digit sequence quantifier with global modifier
var sequance_pattern1 = "2, 0, 200, 2000, 100";
let input_pattern = /\d{3}/g;
var quant_sequance1 = input_pattern.test(sequance_pattern1); 
var ele = document.getElementById("regex_quant");
ele.innerHTML = "Available Values for three-digit sequence: "+quant_sequance1;
let input_pattern1 = /\d{5}/g;
var quant_sequance2 = input_pattern1.test(sequance_pattern1);  
var ele1 = document.getElementById("regex_quant1");
ele1.innerHTML = "Available Values for five-digit sequence: "+quant_sequance2;
}
</script>
</body>
</html>

输出

该量词作用于测试三到五位数字序列。

示例 4

该示例将全局和不区分大小写的修饰符与 regexp{x} 量词一起使用。我们可以看到修饰符对一位数字范围的字符的不同。

<!DOCTYPE html>
<html>
<head>
<title>
JavaScript Regex quantifier
</title>
<style>
#demo1{
background-color: orange;
border: 1px solid black;
width: 370px;
}
</style>
</head>
<body>
<div id = "demo1">
<h3>
JavaScript RegExp {x} quantifier
</h3>
<h4> The regex quantifier operates for one digit with case-insensitive and global modifier:
</h4>
<div id = "regex_quant"></div>
<div id = "regex_quant1"></div>
<!-- click the button for the result -->
<button onclick = "display_group();"> Click Here! </button>
</div>
<script>
function display_group() {
//use Java for single sequence quantifier with global modifier
var sequance_pattern1 = "java JAVA javascript language";
let input_pattern = /\java{1}/g;
var quant_sequance1 = sequance_pattern1.match(input_pattern); 
var ele = document.getElementById("regex_quant");
ele.innerHTML = "Available Values for one digit sequence: "+quant_sequance1;
//use Java for single sequence quantifier with modifiers
let input_pattern1 = /\java{1}/gi;
var quant_sequance2 = sequance_pattern1.match(input_pattern1); 
var ele1 = document.getElementById("regex_quant1");
ele1.innerHTML = "Available Values for one digit sequence: "+quant_sequance2;
}
</script>
</body>
</html>

输出

该量词测试一位数字序列的可用性。

示例 5

正则表达式量词使用 replace 方法替换输入字符串的值。我们可以使用任何替换值并将其放在方法中。

<!DOCTYPE html>
<html>
<head>
<title>
JavaScript RegExp quantifier
</title>
<style>
#demo1{
background-color: orange;
border: 1px solid black;
width: 370px;
}
</style>
</head>
<body>
<div id = "demo1">
<h3>
JavaScript RegExp {x} quantifier with the replace method
</h3>
<div id = "regex_quant"> </div>
<!-- click the button for the result -->
<button onclick = "display_group();"> Click Here! </button>
</div>
<script>
function display_group() {
//use Java for single sequence quantifier 
var sequance_pattern1 = "java, PHP, jquery, javascript, reactjs";
let input_pattern = /\java{1}/g;
let data = "node";
// Use the replace method to change the regex value 
var quant_sequance1 = sequance_pattern1.replace(input_pattern, data); 
var ele = document.getElementById("regex_quant");
ele.innerHTML = "Available Values for one digit sequence: "+quant_sequance1;
}
</script>
</body>
</html>

输出

该量词在 JavaScript 中替换给定次数的值。

示例 6

给出的示例使用正则表达式量词搜索值。

<!DOCTYPE html>
<html>
<head>
<title>
JavaScript Regex quantifier
</title>
<style>
#demo1{
background-color: orange;
border: 1px solid black;
width: 370px;
}
</style>
</head>
<body>
<div id = "demo1">
<h3>
JavaScript RegExp {x} quantifier
</h3>
<h4> The regex quantifier operates for one digit with case-insensitive and global modifier:
</h4>
<div id = "regex_quant"></div>
<div id = "regex_quant1"></div>
<!-- click the button for the result -->
<button onclick = "display_group();"> Click Here! </button>
</div>
<script>
function display_group() {
//use Java for single sequence quantifier with global modifier
var sequance_pattern1 = "java JAVA javascript language";
let input_pattern = /\java{1}/g;
var quant_sequance1 = sequance_pattern1.search(input_pattern); 
var ele = document.getElementById("regex_quant");
ele.innerHTML = "Available Values for one digit sequence: "+quant_sequance1;
//use Java for single sequence quantifier with global and case-insensitive modifier
let input_pattern1 = /\java{1}/gi;
var quant_sequance2 = sequance_pattern1.search(input_pattern1); 
var ele1 = document.getElementById("regex_quant1");
ele1.innerHTML = "Available Values for one digit sequence: "+quant_sequance2;
}
</script>
</body>
</html>

输出

该量词搜索数字的可用性。

结论

"x" 量词作用于正则表达式字符串中给定的数字序列。

下一主题Javascript-class-extends

JavaScript RegExp {x} 量词

语法

支持的浏览器

示例

结论

联系信息

关注我们

教程

面试题

在线编译器

Python

Java

.Net Framework

AI, ML and Data Science

Cloud Technology

B.Tech and MCA

Web Technology

PHP

Software Testing

Technical Interview

Java Interview

Python

Web Interview

Database Interview

B.Tech / MCA

Important Interview

Software Testing Interview

Company Interviews

Online Compilers

Multiple Choice Questions

JavaScript 基础

JS 变量和数据类型

JS 控制语句

JavaScript 函数

JavaScript 对象

JS 高级函数

JS Promises & Async/Await

JavaScript DOM

JavaScript JSON 对象

JavaScript 验证

JavaScript Cookies

异常处理

JavaScript 集合

JavaScript 事件

JavaScript OOPs

JavaScript BOM

面试题

选择题

差异

JavaScript Map 方法

JavaScript Handler

JavaScript Number 方法

JavaScript Reflect

JavaScript Symbol

Symbol 属性

JavaScript Math 方法

JavaScript Date 方法

JavaScript DataView

JavaScript Object 方法

JavaScript Set 方法

JavaScript 字符串方法

JavaScript TypedArray 方法

JavaScript WeakMap 方法

JavaScript WeakSet 方法

JavaScript 数组方法

JavaScript RegExp 对象

JavaScript 附加内容

JavaScript 杂项

JavaScript 进阶

问题

Lodash

JavaScript RegExp {x} 量词

语法

支持的浏览器

示例

结论

相关帖子

JavaScript alert()

学习 JavaScript 需要多长时间？

如何在 JavaScript 中创建按钮？

Javascript Regex ignoreCase 属性

10 天 JavaScript Hackerrank 解决方案

十大 JavaScript 动画库

如何在 JavaScript 中绘制圆形？

如何在 JavaScript 中抛出错误

JavaScript Dispatch Event

JavaScript 中的迭代器和生成器

订阅 Tpoint Tech

联系信息

关注我们