(PHP 5, PHP 7, PHP 8)
DOMDocument::loadHTMLFile — Load HTML from a file
The function parses the HTML document in the file named
filename. Unlike loading XML, HTML does not have
to be well-formed to load.
此函数使用 HTML 4 解析器解析输入。这跟现代 Web 浏览器使用的 HTML 5 的解析规则有所不同。根据输入，这可能会导致不同的 DOM 结构。因此，此函数不能安全地用于清理 HTML。
解析 HTML 时的行为取决于所使用的 libxml 版本，尤其是边缘条件和错误处理方面。对于符合
HTML5 规范的解析，请使用 PHP 8.4 中添加的 Dom\HTMLDocument::createFromString()
或 Dom\HTMLDocument::createFromFile()。
例如，某些 HTML 元素在遇到父元素时会默默关闭。HTML 4 和 HTML 5 中自动关闭父元素的规则不同，因此 DOMDocument 看到的最终 DOM 结构可能与 Web 浏览器看到的 DOM 结构不同，这可能使攻击者能够破坏最终的 HTML。
If an empty string is passed as the filename
or an empty file is named, a warning will be generated. This warning
is not generated by libxml and cannot be handled using libxml's error handling
functions.
尽管非正确格式化的 HTML 仍应该被成功调入，但此函数会在遇到错误标记时产生 E_WARNING 错误。libxml 错误处理函数可以用来处理这类错误。
| 版本 | 说明 |
|---|---|
| 8.3.0 | This function now has a tentative bool return type. |
| 8.0.0 |
Calling this function statically will
now throw an Error.
Previously, an E_DEPRECATED was raised.
|
示例 #1 Creating a Document
<?php
$doc = new DOMDocument();
$doc->loadHTMLFile("filename.html");
echo $doc->saveHTML();
?>
The options for surpressing errors and warnings will not work with this as they do for loadXML()
e.g.
<?php
$doc->loadHTMLFile($file, LIBXML_NOWARNING | LIBXML_NOERROR);
?>
will not work.
you must use:
<?php
libxml_use_internal_errors(true);
$doc->loadHTMLFile($file);
?>
and handle the exceptions as neccesarry.<?php
// try this html listing example for all nodes / includes a few getElementsByTagName options:
$file = $DOCUMENT_ROOT. "test.html";
$doc = new DOMDocument();
$doc->loadHTMLFile($file);
// example 1:
$elements = $doc->getElementsByTagName('*');
// example 2:
$elements = $doc->getElementsByTagName('html');
// example 3:
//$elements = $doc->getElementsByTagName('body');
// example 4:
//$elements = $doc->getElementsByTagName('table');
// example 5:
//$elements = $doc->getElementsByTagName('div');
if (!is_null($elements)) {
foreach ($elements as $element) {
echo "<br/>". $element->nodeName. ": ";
$nodes = $element->childNodes;
foreach ($nodes as $node) {
echo $node->nodeValue. "\n";
}
}
}
?>This puts the HTML into a DOM object which can be parsed by individual tags, attributes, etc.. Here is an example of getting all the 'href' attributes and corresponding node values out of the 'a' tag. Very cool....
<?php
$myhtml = <<<EOF
<html>
<head>
<title>My Page</title>
</head>
<body>
<p><a href="/mypage1">Hello World!</a></p>
<p><a href="/mypage2">Another Hello World!</a></p>
</body>
</html>
EOF;
$doc = new DOMDocument();
$doc->loadHTML($myhtml);
$tags = $doc->getElementsByTagName('a');
foreach ($tags as $tag) {
echo $tag->getAttribute('href').' | '.$tag->nodeValue."\n";
}
?>
This should output:
/mypage1 | Hello World!
/mypage2 | Another Hello World!In this post http://softontherocks.blogspot.com/2014/11/descargar-el-contenido-de-una-url_11.html I found a simple way to get the content of a URL with DOMDocument, loadHTMLFile and saveHTML().
function getURLContent($url){
$doc = new DOMDocument;
$doc->preserveWhiteSpace = FALSE;
@$doc->loadHTMLFile($url);
return $doc->saveHTML();
}