I need to convert this:
[video=http://example.com/video.flv]
Into this:
Using PHP - probably regex. A string can contain many of these 'code blocks' and I need to give each video a unique ID. How can I do this? I am sorry, I really don't know much about regex.
Well if they are all standard in their format, why not just use str_replace()?
$s = '[video=http://www.site.com/video.flv]';
$url = str_replace(array('[video=',']'),array('',''),$s);
echo 'click me!';
$cnt = 0;
preg_replace('/\[.*?=(.*?)]/e', '$1', $text);
not tested, will probably blow up and steal your dog, etc...
Related
How can I mass delete tags like these in a document using PHP preg_replace?
<text:alphabetical-index-mark-start text:id="IMark169843024"/>
The only thing that is different from one to another is the number after IMark.
Thank you!
This is something you can fine-tune to whatever you need. But in general terms you can do something like this:
$string = preg_replace('~<text:.*?>~', '', $string);
Demo
Or you can filter it all the way down with something like this:
$string = preg_replace('~<text:alphabetical-index-mark-start text:id="IMark\d{9}"/>~', '', $string);
Demo
Either way, it'll be pretty easy to strip these tags out.
The company I work for have asked me to give them the ability to place a modal box on the web page from the CMS, but do not want to type HTML. As I cannot for the life of me understand regex I can't get it.
The layout of the code they should type is this:
++modal++
Some paragraph text.
Another paragraph.
++endmodal++
The paragraphs are already converted by markdown into <p>paragraph</p>.
So really the match has to be ++modal++ any number of A-Za-z0-9any symbol excluding + ++endmodal++ then replaced with HTML.
I'm not sure it preg_match or preg_replace should be used.
I got this far:
$string = '++modal++<p>Hello</p>++endmodal++';
$pattern = '/\+\+modal\+\+/';
preg_match($pattern, $string, $matches);
Thank you in advance.
EDIT: A to be a bit more clear, I wish to replace the ++modal++ and ++endmodal++ with HTML and leave the middle bit as is.
I don't really think you need a RegEx here as your delimiters remain always the same and always on the same position of the string. Regular expressions are also expensive on resources and as a third counter argument you said you're not fit with them.
So why not use a simple replacement or string trimming if it comes to that.
$search = array('++modal++', '++endmodal++');
$replacement = array('<tag>', '</tag>');
$str = '++modal++<p>Hello</p>++endmodal++';
$result = str_replace($search, $replacement, $str);
Where, of course, '<tag>' and '</tag>' are just example placeholders for your replacement.
This is what the manual for str_replace() says:
If you don't need fancy replacing rules (like regular expressions),
you should always use this function instead of preg_replace().
I think you should get your desired content using:
preg_match('/\+\+modal\+\+([^\+]+)\+\+endmodal\+\+/', $string, $matches)
$matches[1] = '<p>Hello</p>
You're trying to re-invent the wheel here. You're trying to write a simple template system here, but there are dozens of templating tools for PHP that you could use, ranging from big and complex like Smarty and Twig to really simple ones that aren't much more than you're trying to write.
I haven't used them all, so rather than recommend one I'll point you to a list of template engines you could try. You'll probably find more with a quick bit of googling.
If you do insist on writing your own, it's important to consider security. If you're outputting anything that contains data entered by your users, you must make sure all your output is properly escaped and sanitised for display on a web page; there a numerous common hacks that can take advantage of an insecure templating system to completely compromise a site.
<?php
$string = '++modal++<p>Hello</p>++endmodal++';
$patterns = array();
$patterns[0] = "/\+\+modal\+\+/"; // put '\' just before +
$patterns[1] = "/\+\+endmodal\+\+/";
$replacements = array();
$replacements[1] = '<html>';
$replacements[0] = '</html>';
echo preg_replace($patterns, $replacements, $string);
?>
Very similar to this example
Hi I'm using php to program my site and I've been reading loads about preg_match and trying lots of examples. What I'm trying to do is something like below...
if(preg_match('These characters'), $myVariable, matches)){
Find and remove found characters from $myVariable;
}
I'm pretty sure this is obvious to php experts but it's had me stuck after hours of trying and reading.
Thanks in advance
You don't need to check for a match before doing a replace. It's like if you were to do:
str_replace("A","B","ZZZZZZZ");
It just won't replace anything. Same goes for preg_replace: If there is no match, it just does nothing.
It sounds like you should be using preg_replace. If you wanted to remove all y's and o's for example you would do this:
$string = 'hey you guys!';
$ans = preg_replace('/[yo]/','',$string);
print_r($ans); //outputs 'he u gus!'
Whatever characters you want to remove, just put them between the brackets [...]
I want to give users some formatting options like Reddit or stackOverFlow do, but want to keep it in PHP. How can parse a string in PHP such that it recognizes patterns like **[anything here]**?
explode() doesn't seem to solve the problem as elegantly as I'd like. Should I just use nested ifs and fors based on explode()'s output? Is there a better solution here?
This has already been done countless times by others, I'd recommend using existing libraries.
For example, you can use Markdown: http://michelf.com/projects/php-markdown/
Check regular expressions:
$string = '*bold* or _underscored_ or even /italic/ ..';
// italic
$string = preg_replace('~/([^/]+)/~', '<i>$1</i>', $string);
// bold
$string = preg_replace('/\*([^\*]+)\*/', '<b>$1</b>', $string);
// underscore
$string = preg_replace('/_([^_]+)_/', '<u>$1</u>', $string);
echo $string;
output:
<b>bold</b> or <u>underscored</u> or even <i>italic</i> ..
or use a BBCode parser.
Consider this string
hello awesome <a href="" rel="external" title="so awesome is cool"> stuff stuff
What regex could I use to match any occurence of awesome which doesn't appear within the title attribute of the anchor?
So far, this is what I've came up with (it doesn't work sadly)
/[^."]*(awesome)[^."]*/i
Edit
I took Alan M's advice and used a regex to capture every word and send it to a callback. Thanks Alan M for your advice. Here is my final code.
$plantDetails = end($this->_model->getPlantById($plantId));
$botany = new Botany_Model();
$this->_botanyWords = $botany->getArray();
foreach($plantDetails as $key=>$detail) {
$detail = preg_replace_callback('/\b[a-z]+\b/iU', array($this, '_processBotanyWords'), $detail);
$plantDetails[$key] = $detail;
}
And the _processBotanyWords()...
private function _processBotanyWords($match) {
$botanyWords = $this->_botanyWords;
$word = $match[0];
if (array_key_exists($word, $botanyWords)) {
return '' . $word . '';
} else {
return $word;
}
}
Hope this well help someone else some day! Thanks again for all your answers.
This subject comes up pretty much every day here and basically the issue is this: you shouldn't be using regular expressions to parse or alter HTML (or XML). That's what HTML/XML parsers are for. The above problem is just one of the issues you'll face. You may get something that mostly works but there'll still be corner cases where it doesn't.
Just use an HTML parser.
Asssuming this is related to the question you posted and deleted a little while ago (that was you, wasn't it?), it's your fundamental approach that's wrong. You said you were generating these HTML links yourself by replacing words from a list of keywords. The trouble is that keywords farther down the list sometimes appear in the generated title attributes and get replaced by mistake--and now you're trying to fix the mistakes.
The underlying problem is that you're replacing each keyword using a separate call to preg_replace, effectively processing the entire text over and over again. What you should do is process the text once, matching every single word and looking it up in your list of keywords; if it's on the list, replace it. I'm not set up to write/test PHP code, but you probably want to use preg_replace_callback:
$text = preg_replace_callback('/\b[A-Za-z]+\b/', "the_callback", $text);
"the_callback" is the name of a function that looks up the word and, if it's in the list, generates the appropriate link; otherwise it returns the matched word. It may sound inefficient, processing every word like this, but in fact it's a great deal more efficient than your original approach.
Sure, using a parsing library is the industrial-strength solution, but we all have times were we just want to write something in 10 seconds and be done. Next time you want to process the meaty text of a page, ignoring tags, try just run your input through strip_tags first. This way you will get only the plain, visible text and your regex powers will again reign supreme.
This is so horrible I hesitate to post it, but if you want a quick hack, reverse the problem--instead of finding the stuff that isn't X, find the stuff that IS, change it, do the thing and change it back.
This is assuming you're trying to change awesome (to "wonderful"). If you're doing something else, adjust accordingly.
$string = 'Awesome is the man who <b>awesome</b> does and awesome is.';
$string = preg_replace('#(title\s*=\s*\"[^"]*?)awesome#is', "$1PIGDOG", $string);
$string = preg_replace('#awesome#is', 'wonderful', $string);
$string = preg_replace('#pigdog#is', 'awesome', $string);
Don't vote me down. I know it's hack.