正则表达式 – PHP preg_match_all限制

例：

<?php 
// essential for huge PCREs
ini_set("pcre.backtrack_limit","23001337");
ini_set("pcre.recursion_limit","23001337");
// imagine your PCRE here...
?>

要真正解决底层问题,必须优化表达式并(如果可能)将复杂表达式拆分为“部分”并将一些逻辑移到PHP.我希望你通过阅读这个例子得到这个想法..而不是试图用一个PCRE直接找到子结构,我展示了一种更加“迭代”的方法,使用PHP更深入地进入结构.例：

<?php
$html = file_get_contents("huge_input.html");

// first find all tables,and work on those later
$res = preg_match_all("!<table.*>(?P<content>.*)</table>!isU",$html,$table_matches);

if ($res) foreach($table_matches['content'] as $table_match) {  

    // now find all cells in each table that was found earlier ..
    $res = preg_match_all("!<td.*>(?P<content>.*)</td>!isU",$table_match,$cell_matches);

    if ($res) foreach($cell_matches['content'] as $cell_match) {

        // imagine going deeper and deeper into the structure here...
        echo "found a table cell! content: ",$cell_match;

    }    
}