I need some help to tweak this regular expression:
$content = 'more test test Jeff this is a test';
$content = preg_replace("~<a .*?href=[\'|\"]mailto:(.*?)[\'|\"].*?>.*?</a>~", "$1", $content);
This expression is to strip the html markup off a mailto link and just return the email (jeff#test.com)
It works fine except for in the example I gave above - because a unlimited number of whitespaces is allowed before the href in the pattern, when a website link is before the mailto link, the regex looks all the way forward until it finds the mailto: in the following link and removes all the content in between.
maybe a fix would be to just limit it to two or three whitespaces after the opening tag so as to not look so far ahead, but i wonder if there is a better solution from people who know regex better than I?
Here is what you should be using...
$dom = new DOMDocument;
$dom->loadHTML($content);
foreach($dom->getElementsByTagName('a') as $a) {
if ($a->hasAttribute('href')
AND strpos($href = trim($a->getAttribute('href')), 'mailto:') === 0) {
$textNode = $dom->createTextNode(substr($href, 7));
$parent = $a->parentNode;
$parent->insertBefore($textNode, $a);
$parent->removeChild($a);
}
}
CodePad.
$dom->saveHTML() adds all the HTML boiler plate stuff such as html and body element, you can remove them with...
$html = '';
foreach($dom->getElementsByTagName('body')->item(0)->childNodes as $node) {
$html .= $dom->saveHTML($node);
}
CodePad.
The problem is not to allow any amount of whitespace, that would be working. The problem is you allow one space and any amount of ANY character with your <a .*
If you fix this and allow really only whitespace like this
<a\s+href=[\'|\"]mailto:(.*?)[\'|\"].*?>.*?</a>
it seems to work.
See it here at Regexr
But probably you should have a closer look at alex answer (+1 for the example) as this would be the cleaner solution.
Related
I have a some html paragraphs and I want to wrap every word in . Now I have
$paragraph = "This is a paragraph.";
$contents = explode(' ', $paragraph);
$i = 0;
$span_content = '';
foreach ($contents as $c){
$span_content .= '<span>'.$c.'</span> ';
$i++;
}
$result = $span_content;
The above codes work just fine for normal cases, but sometimes the $paragraph would contains some html tags, for example
$paragraph = "This is an image: <img src='/img.jpeg' /> This is a <a href='/abc.htm'/>Link</a>'";
How can I not wrap "words" inside html tag so that the htmnl tags still works but have the other words wrapped in spans? Thanks a lot!
Some (*SKIP)(*FAIL) mechanism?
<?php
$content = "This is an image: <img src='/img.jpeg' /> ";
$content .= "This is a <a href='/abc.htm'/>Link</a>";
$regex = '~<[^>]+>(*SKIP)(*FAIL)|\b\w+\b~';
$wrapped_content = preg_replace($regex, "<span>\\0</span>", $content);
echo $wrapped_content;
See a demo on ideone.com as well as on regex101.com.
To leave out the Link as well, you could go for:
(?:<[^>]+> # same pattern as above
| # or
(?<=>)\w+(?=<) # lookarounds with a word
)
(*SKIP)(*FAIL) # all of these alternatives shall fail
|
(\b\w+\b)
See a demo for this on on regex101.com.
The short version is you really do not want to attempt this.
The longer version: If you are dealing with HTML then you need an HTML parser. You can't use regexes. But where it becomes even more messy is that you are not starting with HTML, but with an HTML fragment (which may, or may not be well-formed. It might work if Hence you need to use an HTML praser to identify the non-HTML extents, separate them out and feed them into a secondary parser (which might well use regexes) for translation, then replace the translted content back into the DOM before serializing the document.
How can I exclude href matches for a domain (ex. one.com)?
My current code:
$str = 'This string has one link and another link';
$str = preg_replace('~<a href="(https?://[^"]+)".*?>.*?</a>~', '$1', $str);
echo $str; // This string has http://one.com and http://two.com
Desired result:
This string has one link and http://two.com
Using a regular expression
If you're going to use a regular expression to accomplish this task, you can use a negative lookahead. It basically asserts that the part // in the href attribute is not followed by one.com. It's important to note that a lookaround assertion doesn't consume any characters.
Here's how the regular expression would look like:
<a href="(https?://(?!one\.com)[^"]+)".*?>.*?</a>
Regex Visualization:
Regex101 demo
Using a DOM parser
Even though this is a pretty simple task, the correct way to achieve this would be using a DOM parser. That way, you wouldn't have to change the regex if the format of your markup changes in future. The regex solution will break if the <a> node contains more attribute values. To fix all those issues, you can use a DOM parser such as PHP's DOMDocument to handle the parsing:
Here's how the solution would look like:
$dom = new DOMDocument();
$dom->loadHTML($html); // $html is the string containing markup
$links = $dom->getElementsByTagName('a');
//Loop through links and replace them with their anchor text
for ($i = $links->length - 1; $i >= 0; $i--) {
$node = $links->item($i);
$text = $node->textContent;
$href = $node->getAttribute('href');
if ($href !== 'http://one.com') {
$newTextNode = $dom->createTextNode($text);
$node->parentNode->replaceChild($newTextNode, $node);
}
}
echo $dom->saveHTML();
Live Demo
This should do it:
<a href="(https?://(?!one\.com)[^"]+)".*?>.*?</a>
We use a negative lookahead to make sure that one.com does not appear directly after the https?://.
If you also want to check for some subdomains of one.com, use this example:
<a href="(https?://(?!((www|example)\.)?one\.com)[^"]+)".*?>.*?</a>
Here we optionally check for www. or example. before one.com. This will allow a URL like misc.com, though. If you want to remove all subdomains of one.com, use this:
<a href="(https?://(?!([^.]+\.)?one\.com)[^"]+)".*?>.*?</a>
I have code with several lines like this
<p> <inset></p>
Where there may be any number of spaces or tabs (or none) between the opening <p> tag and the rest if the string. I need to replace these, but I can't get it to work.
I thought this would do it, but it doesn't work:
<p>[ \t]+<inset></p>
Try this:
$html = preg_replace('#(<p>)\s+(<inset></p>)#', '$1$2', $html);
If you want true text-trimming for HTML including everything you can encounter like those entitites, comments, child-elements and all that stuff, you can make use of a TextRangeTrimmer and TextRange:
$htmlFragment = '<p> <inset></p>';
$dom = new DOMDocument();
$dom->loadHTML($htmlFragment);
$parent = $dom->getElementsByTagName('body')->item(0);
if (!$parent)
{
throw new Exception('Parent element not found.');
}
$range = new TextRange($parent);
$trimmer = new TextRangeTrimmer($range);
$trimmer->ltrim();
// inner HTML (PHP >= 5.3.6)
foreach($parent->childNodes as $node)
{
echo $dom->saveHTML($node);
}
Output:
<p><inset></p>
I've both classes in a gist: https://gist.github.com/1894360/ (codepad viper is down).
See as well the related questions / answers:
Wordwrap / Cut Text in HTML string
Ignore html tags in preg_replace
Try to load your HTML string into a DOM tree instead, and then trim all the text values in the tree.
http://php.net/domdocument.loadhtml
http://php.net/trim
I need to find and replace all text matches in a case insensitive way, unless the text is within an anchor tag - for example:
<p>Match this text and replace it</p>
<p>Don't match this text</p>
<p>We still need to match this text and replace it</p>
Searching for 'match this text' would only replace the first instance and last instance.
[Edit] As per Gordon's comment, it may be preferred to use DOMDocument in this instance. I'm not at all familiar with the DOMDocument extension, and would really appreciate some basic examples for this functionality.
Here is an UTF-8 safe solution, which not only works with properly formatted documents, but also with document fragments.
The mb_convert_encoding is needed, because loadHtml() seems to has a bug with UTF-8 encoding (see here and here).
The mb_substr is trimming the body tag from the output, this way you get back your original content without any additional markup.
<?php
$html = '<p>Match this text and replace it</p>
<p>Don\'t match this text</p>
<p>We still need to match this text and replace itŐŰ</p>
<p>This is a link <span>with <strong>don\'t match this text</strong> content</span></p>';
$dom = new DOMDocument();
// loadXml needs properly formatted documents, so it's better to use loadHtml, but it needs a hack to properly handle UTF-8 encoding
$dom->loadHtml(mb_convert_encoding($html, 'HTML-ENTITIES', "UTF-8"));
$xpath = new DOMXPath($dom);
foreach($xpath->query('//text()[not(ancestor::a)]') as $node)
{
$replaced = str_ireplace('match this text', 'MATCH', $node->wholeText);
$newNode = $dom->createDocumentFragment();
$newNode->appendXML($replaced);
$node->parentNode->replaceChild($newNode, $node);
}
// get only the body tag with its contents, then trim the body tag itself to get only the original content
echo mb_substr($dom->saveXML($xpath->query('//body')->item(0)), 6, -7, "UTF-8");
References:
1. find and replace keywords by hyperlinks in an html fragment, via php dom
2. Regex / DOMDocument - match and replace text not in a link
3. php problem with russian language
4. Why Does DOM Change Encoding?
I read dozens of answers in the subject, so I am sorry if I forgot somebody (please comment it and I will add yours as well in this case).
Thanks for Gordon and stillstanding for commenting on my other answer.
Try this one:
$dom = new DOMDocument;
$dom->loadHTML($html_content);
function preg_replace_dom($regex, $replacement, DOMNode $dom, array $excludeParents = array()) {
if (!empty($dom->childNodes)) {
foreach ($dom->childNodes as $node) {
if ($node instanceof DOMText &&
!in_array($node->parentNode->nodeName, $excludeParents))
{
$node->nodeValue = preg_replace($regex, $replacement, $node->nodeValue);
}
else
{
preg_replace_dom($regex, $replacement, $node, $excludeParents);
}
}
}
}
preg_replace_dom('/match this text/i', 'IT WORKS', $dom->documentElement, array('a'));
This is the stackless non-recursive approach using pre-order traversal of the DOM tree.
libxml_use_internal_errors(TRUE);
$dom=new DOMDocument('1.0','UTF-8');
$dom->substituteEntities=FALSE;
$dom->recover=TRUE;
$dom->strictErrorChecking=FALSE;
$dom->loadHTMLFile($file);
$root=$dom->documentElement;
$node=$root;
$flag=FALSE;
for (;;) {
if (!$flag) {
if ($node->nodeType==XML_TEXT_NODE &&
$node->parentNode->tagName!='a') {
$node->nodeValue=preg_replace(
'/match this text/is',
$replacement, $node->nodeValue
);
}
if ($node->firstChild) {
$node=$node->firstChild;
continue;
}
}
if ($node->isSameNode($root)) break;
if ($flag=$node->nextSibling)
$node=$node->nextSibling;
else
$node=$node->parentNode;
}
echo $dom->saveHTML();
libxml_use_internal_errors(TRUE); and the 3 lines of code after $dom=new DOMDocument; should be able to handle any malformed HTML.
$a='<p>Match this text and replace it</p>
<p>Don\'t match this text</p>
<p>We still need to match this text and replace it</p>';
echo preg_replace('~match this text(?![^<]*</a>)~i','replacement',$a);
The negative lookahead ensures the replacement happens only if the next tag is not a closing link . It works fine with your example, though it won't work if you happen to use other tags inside your links.
You can use PHP Simple HTML DOM Parser. It is similar to DOMDocument, but in my opinion it's simpler to use.
Here is the alternative in parallel with Netcoder's DomDocument solution:
function replaceWithSimpleHtmlDom($html_content, $search, $replace, $excludedParents = array()) {
require_once('simple_html_dom.php');
$html = str_get_html($html_content);
foreach ($html->find('text') as $element) {
if (!in_array($element->parent()->tag, $excludedParents))
$element->innertext = str_ireplace($search, $replace, $element->innertext);
}
return (string)$html;
}
I have just profiled this code against my DomDocument solution (witch prints the exact same output), and the DomDocument is (not surprisingly) way faster (~4ms against ~77ms).
<?php
$a = '<p>Match this text and replace it</p>
<p>Don\'t match this text</p>
<p>We still need to match this text and replace it</p>
';
$res = preg_replace("#[^<a.*>]match this text#",'replacement',$a);
echo $res;
?>
This way works. Hope you want realy case sensitive, so match with small letter.
HTML parsing with regexs is a huge challenge, and they can very easily end up getting too complex and taking up loads of memory. I would say the best way is to do this:
preg_replace('/match this text/i','replacement text');
preg_replace('/(<a[^>]*>[^(<\/a)]*)replacement text(.*?<\/a)/is',"$1match this text$3");
If your replacement text is something which might occur otherwise, you might want to add an intermediate step with some unique identifier.
I need to convert
$text = 'We had <i>fun</i>. Look at this photo of Joe';
[Edit] There could be multiple links in the text.
to
$text = 'We had fun. Look at this photo (http://example.com) of Joe';
All HTML tags are to be removed and the href value from <a> tags needs to be added like above.
What would be an efficient way to solve this with regex? Any code snippet would be great.
First do a preg_replace to keep the link. You could use:
preg_replace('(.*?)', '$\2 ($\1)', $str);
Then use strip_tags which will finish off the rest of the tags.
try an xml parser to replace any tag with it's inner html and the a tags with its href attribute.
http://www.php.net/manual/en/book.domxml.php
The DOM solution:
$dom = new DOMDocument;
$dom->loadHTML($html);
$xpath = new DOMXPath($dom);
foreach($xpath->query('//a[#href]') as $node) {
$textNode = new DOMText(sprintf('%s (%s)',
$node->nodeValue, $node->getAttribute('href')));
$node->parentNode->replaceChild($textNode, $node);
}
echo strip_tags($dom->saveHTML());
and the same without XPath:
$dom = new DOMDocument;
$dom->loadHTML($html);
foreach($dom->getElementsByTagName('a') as $node) {
if($node->hasAttribute('href')) {
$textNode = new DOMText(sprintf('%s (%s)',
$node->nodeValue, $node->getAttribute('href')));
$node->parentNode->replaceChild($textNode, $node);
}
}
echo strip_tags($dom->saveHTML());
All it does is load any HTML into a DomDocument instance. In the first case it uses an XPath expression, which is kinda like SQL for XML, and gets all links with an href attribute. It then creates a text node element from the innerHTML and the href attribute and replaces the link. The second version just uses the DOM API and no Xpath.
Yes, it's a few lines more than Regex but this is clean and easy to understand and it won't give you any headaches when you need to add additional logic.
I've done things like this using variations of substring and replace. I'd probably use regex today but you wanted an alternative so:
For the <i> tags, I'd do something like:
$text = replace($text, "<i>", "");
$text = replace($text, "</i>", "");
(My php is really rusty, so replace may not be the right function name -- but the idea is what I'm sharing.)
The <a> tag is a bit more tricky. But, it can be done. You need to find the point that <a starts and that the > ends with. Then you extract the entire length and replace the closing </a>
That might go something like:
$start = strrpos( $text, "<a" );
$end = strrpos( $text, "</a>", $start );
$text = substr( $text, $start, $end );
$text = replace($text, "</a>", "");
(I don't know if this will work, again the idea is what I want to communicate. I hope the code fragments help but they probably don't work "out of the box". There are also a lot of possible bugs in the code snippets depending on your exact implementation and environment)
Reference:
strrpos - http://www.php.net/manual/en/function.strrpos.php
replace - http://www.php.net/manual/en/function.str-replace.php
substr - http://php.net/manual/en/function.substr.php
It's also very easy to do with a parser:
# available from http://simplehtmldom.sourceforge.net
include('simple_html_dom.php');
# parse and echo
$html = str_get_html('We had <i>fun</i>. Look at this photo of Joe');
$a = $html->find('a');
$a[0]->outertext = "{$a[0]->innertext} ( {$a[0]->href} )";
echo strip_tags($html);
And that produces the code you want in your test case.