使用PHP的HTML DOMDocument解析HTML [英] Parse HTML with PHP's HTML DOMDocument
问题描述
我试图用getElementsByTagName来实现，但它不起作用，我刚刚使用DOMDocument来解析HTML，因为我曾经使用过正则表达式，直到昨天某种形式的fics告诉我DOMEDocument会是更好的工作，所以我给它一个尝试：）
我谷歌了一段时间寻找一些解释，但没有发现任何有帮助（不所以我想捕捉捕获这个文本1和捕获这个文本2等。
看起来并不难，但我无法弄清楚：（$ / b>
<
< div>
< / div>
< div class =main>
< div class =text>
捕获此文本2
< / div>
< / div>
：
- 文字 li>
- 位于
< div>标记内，并且class =text - 也就是它本身在
< div>中，并且class =main
我会说最简单的方法不是使用 DOMDocument :: getElementsByTagName - 将会返回所有标签有一个特定的名称（虽然你只需要其中的一些）。
相反，我会在文档上使用XPath查询，使用 DOMXpath
例如，像这样的东西应该这样做，将HTML字符串加载到DOM对象，并实例 DOMXpath 类：
$ html =<< ;< HTML
< div class =main>
< div class =text>
捕获此文本1
< / div>
< / div>
< div class =main>
< div class =text>
捕获此文本2
< / div>
< / div>
HTML;
$ dom = new DOMDocument（）;
$ dom-> loadHTML（$ html）;
$ xpath = new DOMXPath（$ dom）;
然后，您可以使用XPath查询， DOMXPath :: query 方法，它返回您正在搜索的元素列表：
$ tags = $ xpath- >查询（ '// DIV [@类= 主] /格[@类= 文本]'）;
foreach（$ tags as $ tag）{
var_dump（trim（$ tag-> nodeValue））;
}
执行这个操作会得到以下输出结果：
string'Capture this text 1'（length = 19）
string'Capture this text 2'（length = 19）
I was trying to do it with "getElementsByTagName", but it wasn't working, I'm new to using DOMDocument to parse HTML, as I used to use regex until yesterday some kind fokes here told me that DOMEDocument would be better for the job, so I'm giving it a try :)
I google around for a while looking for some explains but didn't find anything that helped (not with the class anyway)
So I want to capture "Capture this text 1" and "Capture this text 2" and so on.
Doesn't look to hard, but I can't figure it out :(
<div class="main">
<div class="text">
Capture this text 1
</div>
</div>
<div class="main">
<div class="text">
Capture this text 2
</div>
</div>
If you want to get :
- The text
- that's inside a
<div>tag withclass="text" - that's, itself, inside a
<div>withclass="main"
I would say the easiest way is not to use DOMDocument::getElementsByTagName -- which will return all tags that have a specific name (while you only want some of them).
Instead, I would use an XPath query on your document, using the DOMXpath class.
For example, something like this should do, to load the HTML string into a DOM object, and instance the DOMXpath class :
$html = <<<HTML
<div class="main">
<div class="text">
Capture this text 1
</div>
</div>
<div class="main">
<div class="text">
Capture this text 2
</div>
</div>
HTML;
$dom = new DOMDocument();
$dom->loadHTML($html);
$xpath = new DOMXPath($dom);
And, then, you can use XPath queries, with the DOMXPath::query method, that returns the list of elements you were searching for :
$tags = $xpath->query('//div[@class="main"]/div[@class="text"]');
foreach ($tags as $tag) {
var_dump(trim($tag->nodeValue));
}
And executing this gives me the following output :
string 'Capture this text 1' (length=19)
string 'Capture this text 2' (length=19)
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