使用 PHP 获取 DOM 元素
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Using PHP to get DOM Element
提问by Matt
I'm struggling big time understanding how to use the DOMElement object in PHP. I found this code, but I'm not really sure it's applicable to me:
我正在努力理解如何在 PHP 中使用 DOMElement 对象。我找到了这段代码，但我不确定它是否适用于我：
$dom = new DOMDocument();
$dom->loadHTML("index.php");
$div = $dom->getElementsByTagName('div');
foreach ($div->attributes as $attr) {
$name = $attr->nodeName;
$value = $attr->nodeValue;
echo "Attribute '$name' :: '$value'<br />";
}
Basically what I need is to search the DOM for an elementwith a particular id, after which point I need to extract a non-standard attribute(i.e. one that I made up and put on with JS) so I can see the value of that. The reason is I need one piece from the $_GETand one piece that is in the HTML based from a redirect. If someone could just explain how I use DOMDocument for this purpose, that would be helpful. I'm really struggling understanding what's going on and how to properly implement it, because I clearly am not doing it right.
基本上，我需要的是搜索DOM为element与特定的id，在此之后我需要提取非标准attribute（即一个，我做起来，把与JS），所以我可以看到该值。原因是我需要一个来自$_GET和 来自基于重定向的 HTML 中的一个。如果有人可以解释我如何为此目的使用 DOMDocument，那会很有帮助。我真的很难理解正在发生的事情以及如何正确实施它，因为我显然做得不对。
EDIT (Where I'm at based on comment):
编辑（根据评论我所在的位置）：
This is my code lines 4-26 for reference:
这是我的代码第 4-26 行以供参考：
<div id="column_profile">
<?php
require_once($_SERVER["DOCUMENT_ROOT"] . "/peripheral/profile.php");
$searchResults = isset($_GET["s"]) ? performSearch($_GET["s"]) : "";
$dom = new DOMDocument();
$dom->load("index.php");
$divs = $dom->getElementsByTagName('div');
foreach ($divs as $div) {
foreach ($div->attributes as $attr) {
$name = $attr->nodeName;
$value = $attr->nodeValue;
echo "Attribute '$name' :: '$value'<br />";
}
}
$div = $dom->getElementById('currentLocation');
$attr = $div->getAttribute('srckey');
echo "<h1>{$attr}</a>";
?>
</div>
<div id="column_main">
Here is the error message I'm getting:
这是我收到的错误消息：
Warning: DOMDocument::load() [domdocument.load]: Extra content at the end of the document in ../public_html/index.php, line: 26 in ../public_html/index.php on line 10
Fatal error: Call to a member function getAttribute() on a non-object in ../public_html/index.php on line 21
回答by Rocket Hazmat
getElementsByTagNamereturns you a list of elements, so first you need to loop through the elements, then through their attributes.
getElementsByTagName返回一个元素列表，所以首先你需要遍历元素，然后遍历它们的属性。
$divs = $dom->getElementsByTagName('div');
foreach ($divs as $div) {
foreach ($div->attributes as $attr) {
$name = $attr->nodeName;
$value = $attr->nodeValue;
echo "Attribute '$name' :: '$value'<br />";
}
}
In your case, you said you needed a specific ID. Those are supposed to be unique, so to do that, you can use (note getElementByIdmight not work unless you call $dom->validate()first):
在您的情况下，您说您需要一个特定的 ID。这些应该是独一无二的，所以要做到这一点，你可以使用（注意getElementById可能无法工作，除非你$dom->validate()先打电话）：
$div = $dom->getElementById('divID');
Then to get your attribute:
然后获取你的属性：
$attr = $div->getAttribute('customAttr');
EDIT: $dom->loadHTMLjust reads the contents of the file, it doesn't execute them. index.phpwon't be ran this way. You might have to do something like:
编辑：$dom->loadHTML只读取文件的内容，不执行它们。 index.php不会以这种方式运行。您可能必须执行以下操作：
$dom->loadHTML(file_get_contents('http://localhost/index.php'))
回答by jakx
You won't have access to the HTML if the redirect is from an external server. Let me put it this way: the DOM does not exist at the point you are trying to parse it. What you can do is pass the text to a DOM parser and then manipulate the elements that way. Or the better way would be to add it as another GET variable.
如果重定向来自外部服务器，您将无法访问 HTML。让我这样说：在您尝试解析它时，DOM 不存在。您可以做的是将文本传递给 DOM 解析器，然后以这种方式操作元素。或者更好的方法是将其添加为另一个 GET 变量。
EDIT: Are you also aware that the client can change the HTML and have it pass whatever they want? (Using a tool like Firebug)
编辑：您是否也知道客户端可以更改 HTML 并让它通过任何他们想要的内容？（使用 Firebug 之类的工具）
