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php通过function_exists检测函数是否存在的方法

Jun 06, 2016 pm 08:06 PM
php function exist Detection

这篇文章主要介绍了php通过function_exists检测函数是否存在的方法,实例分析了php使用function_exists检测函数是否存在及调用的相关技巧,非常具有实用价值,需要

本文实例讲述了php通过function_exists检测函数是否存在的方法。分享给大家供大家参考。具体分析如下:

php中可以通过function_exists()函数检测另外一个函数是否存在,可以把函数名作为一个字符串传入function_exists,判断该还是是否存在

function highlight( $txt ) { return "$txt"; } function textWrap( $tag, $txt, $func="" ) { if (function_exists( $func ) ) $txt = $func($txt); return "$txt$tag>\n"; }

用法示例如下:

echo textWrap('i','function exists Demo','highlight'); //输出结果为斜体字的: function exists Demo

希望本文所述对大家的php程序设计有所帮助。

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