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  • preg_replace($pattern, $replacement, $content) 修饰符的奇葩作用

    $str = "<span>lin</span> == <span>3615</span>";
    $pattern = "/<span>(.*)</span>/";
    $str = preg_replace($pattern, "<span class='fuck'>$1</span>", $str);
    print_r($str);

    $pattern 中没有问号

    结果为:<span class='fuck'>lin</span> == <span>3615</span>

    $str = "<span>lin</span> == <span>3615</span>";
    $pattern = "/<span>(.*?)</span>/";
    $str = preg_replace($pattern, "<span class='fuck'>$1</span>", $str);
    print_r($str);

    $pattern 中有问号(相当于防止贪婪匹配)

    结果为:<span class='fuck'>lin</span> == <span class='fuck'>3615</span>

    $str = "<span>lin</span> == <span>3615</span>";
    $pattern = "/<span>(.*)</span>/U";
    $str = preg_replace($pattern, "<span class='fuck'>$1</span>", $str);
    print_r($str);

    $pattern 中无问号( U 防止贪婪匹配)

    结果为:<span class='fuck'>lin</span> == <span class='fuck'>3615</span>

    $str = "<span>lin</span> == <span>3615</span>";
    $pattern = "/<span>(.*?)</span>/U";
    $str = preg_replace($pattern, "<span class='fuck'>$1</span>", $str);
    print_r($str);

    $pattern 中有问号( U 防止贪婪匹配),相当于失去了U的意义

    <span class='fuck'>lin</span> == <span>3615</span>
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  • 原文地址:https://www.cnblogs.com/lin3615/p/3602544.html
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