DomDocument fetch h1 tag - php

I have very very big html page/data. I need to fetch data under h1 tag.
so what I have seen on various example is DOMDOCUMENT is basically used for parsing xml.
but if i have html data, very meshu, and I want to fetch text under <h1></h1> tag then what will be code.
If there are number of <h1> tags
$doc = new DOMDocument();
#$doc->loadHTML($this->siteHtmlData);
$aElements = $doc->getElementsByTagName("h1")
Please help me.
Thanks

You could loop it to get the value:
foreach ($aElementsas as $node) {
echo $node->nodeValue, PHP_EOL;
}

Related

Remove HTML Tag using DOMDocument

I'd like to remove <font> tags from my html and am trying to use replaceChild to do so, but it doesn't seem to work properly. Can anyone catch what might be wrong?
$html = '<html><body><br><font class="heading2">Limited Size and Resources</font><p><br><strong>Q: When can a member use the limited size and resources exception?</strong></p></body></html>';
$dom = new DOMDocument();
$dom->loadHTML($html);
$font_tags = $dom->GetElementsByTagName('font');
foreach($font_tags as $font_tag) {
foreach($font_tag as $child) {
$child->replaceChild($child->nodeValue, $font_tag);
}
}
echo $dom->saveHTML();
From what I understand, $font_tags is a DOMNodeList, so I need to iterate through it twice in order to use the DOMNode::replaceChild function. I then want to replace the current value with just the content inside of the tags. However, when I output the $html nothing changes. Any ideas what could be wrong?
Here is a PHP Sandbox to test the code.
I'll put my remarks inline
$html = '<html><body><br><font class="heading2">Limited Size and Resources</font><p><br><strong>Q: When can a member use the limited size and resources exception?</strong></p></body></html>';
$dom = new DOMDocument();
$dom->loadHTML($html);
$font_tags = $dom->GetElementsByTagName('font');
/* You only need one loop, as it is iterating your collection
You would only need a second loop if each font tag had children of their own
*/
foreach($font_tags as $font_tag) {
/* replaceChild replaces children of the node being called
So, to replace the font tag, call the function on its parent
$prent will be that reference
*/
$prent = $font_tag->parentNode;
/* You can't insert arbitrary text, you have to create a textNode
That textNode must also be a member of your document
*/
$prent->replaceChild($dom->createTextNode($font_tag->nodeValue), $font_tag);
}
echo $dom->saveHTML();
Updated Sandbox: Hopefully I understood your requirements correctly
First, let us find out what wasn't working in your code.
foreach($font_tag as $child) wasn't even iterating once as $font_tag is a single 'font' tag element from font_tags array, and not an array itself.
$child->replaceChild($child->nodeValue, $font_tag); - A child node can't replace its parent ($font_tag), but the reverse is possible.
As replaceChild is a method of the parent node to replace its child.
For more details check the PHP: DOMNode::replaceChild documentation, or the point 2 below my code.
echo $html will output the $html string, but not the updated $dom object that we are modifying.
This would work -
$html = '<html><body><br><font class="heading2">Limited Size and Resources</font><p><br><strong>Q: When can a member use the limited size and resources exception?</strong></p></body></html>';
$dom = new DOMDocument();
$dom->loadHTML($html);
$font_tags = $dom->GetElementsByTagName('font');
foreach($font_tags as $font_tag)
{
$new_node = $dom->createTextNode($font_tag->nodeValue);
$font_tag->parentNode->replaceChild($new_node, $font_tag);
}
echo $dom->saveHTML();
I am creating a $new_node directly in the $dom, so the node is live in the DOMDocument and not any local variable.
To replace the child object $font_tag, we have to first traverse to the parent node using the parentNode method.
Finally, we are printing out the modified $dom using saveHTML method, which will convert the DOMDocument into a HTML String.
Remove a specific span tag from HTML while preserving/keeping the inside content using PHP and DOMDocument
<?php
$content = '<span style="font-family: helvetica; font-size: 12pt;"><div>asdf</div><span>TWO</span>Business owners are fearful of leading. They would rather follow the leader than embrace a bold move that challenges their confidence. </span>';
$dom = new DOMDocument();
// Use LIBXML for preventing output of doctype, <html>, and <body> tags
$dom->loadHTML($content, LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD);
$xpath = new DOMXPath($dom);
foreach ($xpath->query('//span[#style="font-family: helvetica; font-size: 12pt;"]') as $span) {
// Move all span tag content to its parent node just before it.
while ($span->hasChildNodes()) {
$child = $span->removeChild($span->firstChild);
$span->parentNode->insertBefore($child, $span);
}
// Remove the span tag.
$span->parentNode->removeChild($span);
}
// Get the final HTML with span tags stripped
$output = $dom->saveHTML();
print_r($output);

Get "Text-Only" Text With PHP Strip Tags

I'm using PHP Simple HTML DOM Parser. So You Can Use It In Solutions
Okay. So, I'm loading a file like this:
$html = file_get_html('http://localhost/seo/testfile.php');
And I echo the code as echo strip_tags($html);
So far, so good.
The problem occours when user enter inline code like
<script>alert(1)</script>
So I want not to display anything present inside <script>, <style>, etc. tags. How do I do that?
Cheers!
i think php dom will help you and you can get required html of any element and indirectly of whole page. same like below.
$dom = new DOMDocument();
libxml_use_internal_errors(true);
$dom->loadHTML($content);
$data = $dom->getElementsByTagName("tr");
foreach($data as $value){
if($value->getAttribute('class')== 'notesRow'){
$aa = $value->nodeValue;
}
}

php dom document remove some html tags but keep inner tags and text

I need to remove some tags (e.g. <div></div>) in HTML document and keep inner tags and text.
I managed to do that with Simple HTML Dom Parser. But it can't process big files due to huge memory requirements.
I would prefer to use native PHP tools like DOMDocument cause I read that it's more optimized and quicker in processing HTML documents.
But I struggle at the first stage - how to remove some tags while keeping inner text and tags.
Source HTML sample is:
<html><body><div>00000</div>aaaaa<div>bbbbbb<div>ccc<a>link</a>ccc</div>dddddd</div>eeeee<div>1111</div></body></html>
I try this code:
$htmltext='<html><body><div>00000</div>aaaaa<div>bbbbbb<div>ccc<a>link</a>ccc</div>dddddd</div>eeeee<div>1111</div></body></html>';
libxml_use_internal_errors(true);
$doc = new DOMDocument();
$doc->loadHTML($htmltext);
$oldnodes = $doc->getElementsByTagName('div');
foreach ($oldnodes as $node) {
$fragment = $doc->createDocumentFragment();
while($node->childNodes->length > 0) {
$fragment->appendChild($node->childNodes->item(0));
}
$node->parentNode->replaceChild($fragment, $node);
}
echo $doc->saveHTML();
It produces the output:
<html><body>00000aaaaa<div>bbbbbbccc<a>link</a>cccdddddd</div>eeeee<div>1111</div></body></html>
I need the following:
<html><body>00000aaaaabbbbbbccc<a>link</a>cccddddddeeeee1111</body></html>
Could someone please help me with proper code for the task?
You can use strip_tags function in PHP.
$thmltext = '<html><body><div>00000</div>aaaaa<div>bbbbbb<div>ccc<a>link</a>ccc</div>dddddd</div>eeeee<div>1111</div></body></html>';
strip_tags($htmltext, '<html>,<body>,<a>');
This remove all tags except html,body,a
And output is:
<html><body>00000aaaaabbbbbbccc<a>link</a>cccddddddeeeee1111</body></html>
EDIT:
If it is input from user, it's better for security reason to use whitelist tags and not blacklist.
If your code only contains simple HTML tags without any attributes you can keep it simple like:
$value = '<html><body><div>00000</div>aaaaa<div>bbbbbb<div>ccc<a>link</a>ccc</div>dddddd</div>eeeee<div>1111</div></body></html>';
$pattern = '/<[\/]*(div|h1)>/';
$removedTags = preg_replace($pattern, '', $value);
Since you wrote in your comment that there are more than just div tags you want to remove, I added a h1 tag to the pattern in case you also want to remove h1 tags.
This code snippet is only for simple code, but fits to your HTML input and output example.
Try this..
Just replace the for loop with the below code.
foreach ($oldnodes as $node) {
$children = $node->childNodes;
$string = "";
foreach($children as $child) {
$childString = $doc->saveXML($child);
$string = $string."".$childString;
}
$fragment = $doc->createDocumentFragment();
$fragment->appendXML($string);
$node->parentNode->insertBefore($fragment,$node);
$node->parentNode->removeChild($node);
}
I found a way to make it work.
The reason code in question not working is the manipulation with nodes in nodelist ruin nodelist. So "foreach" function wents through only 2 out of 4 items in nodelist - the rest 2 become distorted.
So I had to deal with only the 1st element of the list and then rebuild list until there are some items in the list left.
The code is:
$htmltext='<html><body><div>00000</div>aaaaa<div>bbbbbb<div>ccc<a>link</a>ccc</div>dddddd</div>eeeee<div>1111</div></body></html>';
echo "<!--
".$htmltext."
-->
";
libxml_use_internal_errors(true);
$doc = new DOMDocument();
$doc->loadHTML($htmltext);
$oldnodes = $doc->getElementsByTagName('div');
while ($oldnodes->length>0){
$node=$oldnodes->item(0);
$fragment = $doc->createDocumentFragment();
while($node->childNodes->length > 0) {
$fragment->appendChild($node->childNodes->item(0));
}
$node->parentNode->replaceChild($fragment, $node);
$oldnodes = $doc->getElementsByTagName('div');
}
echo $doc->saveHTML();
I hope that will be helpful for someone who finds same difficulties.

How do I assemble pieces of HTML into a DOMDocument?

It appears that loadHTML and loadHTMLFile for a files representing sections of an HTML document seem to fill in html and body tags for each section, as revealed when I output with the following:
$doc = new DOMDocument();
$doc->loadHTMLFile($file);
$elements = $doc->getElementsByTagName('*');
if( !is_null($elements) ) {
foreach( $elements as $element ) {
echo "<br/>". $element->nodeName. ": ";
$nodes = $element->childNodes;
foreach( $nodes as $node ) {
echo $node->nodeValue. "\n";
}
}
}
Since I plan to assemble these parts into the larger document within my own code, and I've been instructed to use DOMDocument to do it, what can I do to prevent this behavior?
This is part of several modifications the HTML parser module of libxml makes to the document in order to work with broken HTML. It only occurs when using loadHTML and loadHTMLFile on partial markup. If you know the partial is valid X(HT)ML, use load and loadXML instead.
You could use
$doc->saveXml($doc->getElementsByTagName('body')->item(0));
to dump the outerHTML of the body element, e.g. <body>anything else</body> and strip the body element with str_replace or extract the inner html with substr.
$html = '<p>I am a fragment</p>';
$dom = new DOMDocument;
$dom->loadHTML($html); // added html and body tags
echo substr(
$dom->saveXml(
$dom->getElementsByTagName('body')->item(0)
),
6, -7
);
// <p>I am a fragment</p>
Note that this will use XHTML compliant markup, so <br> would become <br/>. As of PHP 5.3.5, there is no way to pass a node to saveHTML(). A bug request has been filed.
The closest you can get is to use the DOMDocumentFragment.
Then you can do:
$doc = new DOMDocument();
...
$f = $doc->createDocumentFragment();
$f->appendXML("<foo>text</foo><bar>text2</bar>");
$someElement->appendChild($f);
However, this expects XML, not HTML.
In any case, I think you're creating an artificial problem. Since you know the behavior is to create the html and body tags you can just extract the elements in the file from within the body tag and then import the, to the DOMDocument where you're assembling the final file. See DOMDocument::importNode.

Add an attribute to an HTML element

I can't quite figure it out, I'm looking for some code that will add an attribute to an HTML element.
For example lets say I have a string with an <a> in it, and that <a> needs an attribute added to it, so <a> gets added style="xxxx:yyyy;". How would you go about doing this?
Ideally it would add any attribute to any tag.
It's been said a million times. Don't use regex's for HTML parsing.
$dom = new DOMDocument();
#$dom->loadHTML($html);
$x = new DOMXPath($dom);
foreach($x->query("//a") as $node)
{
$node->setAttribute("style","xxxx");
}
$newHtml = $dom->saveHtml()
Here is using regex:
$result = preg_replace('/(<a\b[^><]*)>/i', '$1 style="xxxx:yyyy;">', $str);
but Regex cannot parse malformed HTML documents.

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