查找所有 <pre>PHP 中的标签(带属性) [英] Find all <pre> tags in PHP (with attributes)

问题描述

我正在关注这个问题 关于如何在 PHP 中检索所有标签.

特别是(在 wordpress 下)，我想找到所有

 标签，以及所有可用的信息(属性和文字).但是，我似乎不太擅长preg_match，所以我向您求助.
我的文本确实包含各种<pre>标签，一些带有属性，一些带有文本.我的功能是这样的:
function getPreTags($string) {$pattern = "/
(.*)<\/pre>/";preg_match($pattern, $string, $matches);返回 $matches[1];}
我已经简化为只有 one 
 标签的测试，但我得到 count(getPreTags(myHTMLbody)) = 0，我不知道为什么.这是测试字符串:
<pre class="wp-code-highlight Prettyprint Prettyprinted" style=""><span class="com">随便&lt;</span>我已经写了 &gt;>这里应该注意<span class="something"></span></pre>
有什么提示吗?
干杯！
解决方案
一如既往，使用正则表达式解析 HTML 永远不会削减它.有很多事情要考虑(标签汤，间距:
==
==<\n\t\sPrE\n\n>...)，任何正则表达式都会在某些时候使您失败.这就是为什么有解析器之类的东西，随时可用.
也就是说:当你需要 all pre 时，我不知道为什么其他答案会遇到使用 DOMXPath 实例的麻烦> 标签，包括没有属性的标签.
我会选择更简单的东西，例如:
$dom = 新的 DOMDocument;$dom->loadHTML($htmlString);$preTags = $dom->getElementsByTagName('pre');foreach($preTags as $pre){echo $pre->nodeValue, PHP_EOL;if ($pre->hasAttributes()){//如果有属性foreach($pre->attributes as $attribute){//用属性做一些事情echo '属性:', $attribute->name, '=', $attribute->value, PHP_EOL;}}}
可以在这些页面上轻松找到哪些方法和属性可供您使用:
属性:DOMAttr 类文档
节点:DOMNode 类文档
文档:DOMDocument 类文档
I was following this question on how to retrieve all tags in PHP. 

Specifically (under wordpress), I'd like to find all <pre> tags, with all the available information (attributes and text). However, it seems that I'm not that skilled in preg_match, so I'm turning to you. 

My text does contain various <pre> tags, some with attributes, some with just text. My function is this:
function getPreTags($string) {
    $pattern = "/<pre\s?(.*)>(.*)<\/pre>/";
    preg_match($pattern, $string, $matches);
    return $matches[1];
}
I've reduced to a test with just one <pre> tag, but I get count(getPreTags(myHTMLbody)) = 0, and I don't know why. This is the test string:
<pre class="wp-code-highlight prettyprint prettyprinted" style=""><span class="com">Whatever &lt;</span> I've written &gt;&gt; here <span class="something">should be taken care of</span></pre>
Any hint?

Cheers!
解决方案
As ever, parsing HTML with regex is never going to cut it. There are so many things to take into account (tag-soup, spacing: <pre>==<   pre >==<\n\t\sPrE\n\n>...), any regex will fail you at some point. That's why there are such things as parsers, readily available.

That said: I have no idea why the other answers go through the trouble of using an instance of DOMXPath, when you need all pre tags, including those without attributes.

I'd go for something more simple, like:
$dom = new DOMDocument;
$dom->loadHTML($htmlString);
$preTags = $dom->getElementsByTagName('pre');
foreach($preTags as $pre)
{
    echo $pre->nodeValue, PHP_EOL;
    if ($pre->hasAttributes())
    {//if there are attributes
        foreach($pre->attributes as $attribute)
        {
            //do something with attribute
            echo 'Attribute: ', $attribute->name, ' = ', $attribute->value, PHP_EOL;
        }
    }
}
What methods and properties are available to you can be found easily on these pages:


Attributes: DOMAttr class docs
Nodes: DOMNode class docs
Document: DOMDocument class docs


                        
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