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HomeBackend DevelopmentPHP TutorialHow to change the first character color in php


PHP更改字符串中第一个字符的颜色,我们可以通过preg_replace()函数来实现,也就是正则替换的方法。

How to change the first character color in php

下面我们就结合简单的代码示例,给大家介绍PHP更改字符串首个字符颜色的方法。

代码示例如下:

<?php
$text = &#39;PHP Tutorial&#39;;
$text = preg_replace(&#39;/(\b[a-z])/i&#39;,&#39;<span style="color:red;">\1</span>&#39;,$text);
echo $text;

效果如下图所示:

How to change the first character color in php

preg_replace 表示 执行一个正则表达式的搜索和替换。

其语法:

mixed preg_replace ( mixed $pattern , mixed $replacement , mixed $subject [, int $limit = -1 [, int &$count ]] )

搜索subject中匹配pattern的部分, 以replacement进行替换。如果subject参数是数组,则函数返回数组,否则返回字符串。如果找到匹配项,将返回新主题,否则主题将保持不变,如果发生错误则返回NULL。

:PHP 5.5.0 起, 传入 "\e" 修饰符的时候,会产生一个 E_DEPRECATED 错误; PHP 7.0.0 起,会产生 E_WARNING 错误,同时 "\e" 也无法起效。

本篇文章就是关于PHP更改字符串首个字符颜色的方法介绍,非常简单易懂,希望对需要的朋友有所帮助!


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