search
HomeBackend DevelopmentPHP TutorialJavaScript regular method replace implements search keyword highlighting_regular expression

这里介绍的是JavaScript正则表达式的replace方法 ,和实现搜索关键字高亮的功能.先介绍一下正则表达式的replace方法,以下本文含有JavaScript源码和JavaScript源码讲解,一起来看本文详细吧

前言

正则表达式是字符串处理工具中强有力的工具.也有人认为这只是一个小玩具,但不管怎么说都离不开它.

这里介绍的是JavaScript的正则表达式的replace方法 ,和实现搜索关键字高亮的功能.

先介绍一下正则表达式的replace方法

JavaScript regular method replace implements search keyword highlighting_regular expression

JavaScript regular method replace implements search keyword highlighting_regular expression

w3school原文链接介绍

正则表达式如何使用特殊字符$来表示原来的文本,这是实现搜索高亮的关键,


var str = "asad sad 123 sd qwe21";
str.replace(/\d+/img,"数字");
//这里正确的匹配到了数字,且替换成了中文的数字
console.log(str);//"asad sad 数字 sd qwe数字"
------------------------------------------------------
//看一下如何使用$1,表示被捕获的字符串
var str = "asad sad 123 sd qwe21";
str.replace(/\d+/img,"数字$1数字");
console.log(str);//"asad sad 数字$1数字 sd qwe数字$1数字"
//很显然并没有成功,$1 还是$1,那么如何正确使用呢?
------------------------------------------------------
var str = "asad sad 123 sd qwe21";
str.replace(/(\d+)/img,"数字$1数字");
//这里就正确的匹配了数字并且用$1 表示原字符串并替换
console.log(str);///"asad sad 数字123数字 sd qwe数字21数字"
/*
()在正则里面表示捕获性元组,可以用$1 特殊字符来表示被替换的内容,可以有多个()元组,也就是可以有多个$1,$2 */


开始小试身手


<!DOCTYPE html>
<html lang="en">
<head>
</head>
<body>
 <style>
 b{
 color:red;
 }
 </style>
<p id="poetry">
春江花月夜<br>
作者:张若虚<br>
春江潮水连海平,海上明月共潮生。 <br>
滟滟随波千万里,何处春江无月明! <br>
江流宛转绕芳甸,月照花林皆似霰; <br>
空里流霜不觉飞,汀上白沙看不见。 <br>
江天一色无纤尘,皎皎空中孤月轮。 <br>
江畔何人初见月?江月何年初照人? <br>
人生代代无穷已,江月年年只相似。 <br>
</p>
<input type ="text" id="input" />
</body>
</html>
<script>
//input 输入要查找的字符串
input.onchange = function(){
 //获取要查找的字符串
 var searchVal = input.value;
 // 获取要查找的内容
 var text = poetry.innerHTML;
 //将之前的查找高亮的字符串,取消高亮
 text = text.replace(/<b[^>]*>([^>]*)<\/b[^>]*>/ig,"$1");
 poetry.innerHTML = text;
 //初始化正则表达式,加上括号(),形成可捕获元组.ig表示全局匹配和不区分大小写
 var reg = new RegExp("("+searchVal +")","ig");
 //高亮要查找的字符串
 text = text.replace(reg,"<b>$1</b>");
 poetry.innerHTML = text;
}
</script>

以上所述是小编给大家介绍的JavaScript正则方法replace实现搜索关键字高亮显示,希望对大家有所帮助。

相关推荐:

jquery实现类似百度的搜索框

jQuery中select插件实现异步实时搜索的方法

JavaScript正则方法replace实现搜索关键字高亮显示

The above is the detailed content of JavaScript regular method replace implements search keyword highlighting_regular expression. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
The Continued Use of PHP: Reasons for Its EnduranceThe Continued Use of PHP: Reasons for Its EnduranceApr 19, 2025 am 12:23 AM

What’s still popular is the ease of use, flexibility and a strong ecosystem. 1) Ease of use and simple syntax make it the first choice for beginners. 2) Closely integrated with web development, excellent interaction with HTTP requests and database. 3) The huge ecosystem provides a wealth of tools and libraries. 4) Active community and open source nature adapts them to new needs and technology trends.

PHP and Python: Exploring Their Similarities and DifferencesPHP and Python: Exploring Their Similarities and DifferencesApr 19, 2025 am 12:21 AM

PHP and Python are both high-level programming languages ​​that are widely used in web development, data processing and automation tasks. 1.PHP is often used to build dynamic websites and content management systems, while Python is often used to build web frameworks and data science. 2.PHP uses echo to output content, Python uses print. 3. Both support object-oriented programming, but the syntax and keywords are different. 4. PHP supports weak type conversion, while Python is more stringent. 5. PHP performance optimization includes using OPcache and asynchronous programming, while Python uses cProfile and asynchronous programming.

PHP and Python: Different Paradigms ExplainedPHP and Python: Different Paradigms ExplainedApr 18, 2025 am 12:26 AM

PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.

PHP and Python: A Deep Dive into Their HistoryPHP and Python: A Deep Dive into Their HistoryApr 18, 2025 am 12:25 AM

PHP originated in 1994 and was developed by RasmusLerdorf. It was originally used to track website visitors and gradually evolved into a server-side scripting language and was widely used in web development. Python was developed by Guidovan Rossum in the late 1980s and was first released in 1991. It emphasizes code readability and simplicity, and is suitable for scientific computing, data analysis and other fields.

Choosing Between PHP and Python: A GuideChoosing Between PHP and Python: A GuideApr 18, 2025 am 12:24 AM

PHP is suitable for web development and rapid prototyping, and Python is suitable for data science and machine learning. 1.PHP is used for dynamic web development, with simple syntax and suitable for rapid development. 2. Python has concise syntax, is suitable for multiple fields, and has a strong library ecosystem.

PHP and Frameworks: Modernizing the LanguagePHP and Frameworks: Modernizing the LanguageApr 18, 2025 am 12:14 AM

PHP remains important in the modernization process because it supports a large number of websites and applications and adapts to development needs through frameworks. 1.PHP7 improves performance and introduces new features. 2. Modern frameworks such as Laravel, Symfony and CodeIgniter simplify development and improve code quality. 3. Performance optimization and best practices further improve application efficiency.

PHP's Impact: Web Development and BeyondPHP's Impact: Web Development and BeyondApr 18, 2025 am 12:10 AM

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

How does PHP type hinting work, including scalar types, return types, union types, and nullable types?How does PHP type hinting work, including scalar types, return types, union types, and nullable types?Apr 17, 2025 am 12:25 AM

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values ​​and handle functions that may return null values.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

PhpStorm Mac version

PhpStorm Mac version

The latest (2018.2.1) professional PHP integrated development tool

MinGW - Minimalist GNU for Windows

MinGW - Minimalist GNU for Windows

This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

ZendStudio 13.5.1 Mac

ZendStudio 13.5.1 Mac

Powerful PHP integrated development environment