I have a list of badwords one of them is "S.A."
All my words are saved in an array and I loop through the array and do the replacement.
The word S.A. replaces things which I don't want replaced, i need it only to replace S.A. as a word itself.
So example "This S.A. was bad." should become "This was bad".
But now when I run it on a string with (for example) SEAS in it, it will replace it... no idea why...
ps: the if then check is because if the string $v is exactly the badword, it should not be removed.
Shouldn't the \b word indicator in the regex make the word an exact match?
ps: I only want to remove full words, not a part of a word.
If I have Apple in the badlist but someone wrote Apples it should not be replaced.
foreach ($this->badwordArr as $badword) {
if (strtoupper($v) == strtoupper($badword)) {
// no replace because its the only word
$data[$key] = $v;
} else {
$pattern = "/\b$badword\b/i";
$v = preg_replace($pattern, " ", $v);
}
}
What's wrong with my regex pattern?!?!
The dot is a meta character in a regex that represents any character. You need to escape it:
S\.A\.
To avoid revising your whole list, you can use:
$badword_escaped = preg_quote($badword);
$pattern = "/\b$badword_escaped\b/i";
Related
I have an array of words
$banned_names = array('about','access','account');
The actual array is very long a contains bad words so at risk of breaking any rule I just added an example, the issue I'm having is the following:
$title = str_ireplace($filterWords, '****', $dn1['title']);
This works however, one of my filtered words is 'rum' and if I was to post the word 'forum' it will display as 'fo****'
So I need to only replace the word with **** if it matches the exact word from the array, if I was to give an example the phrase "Lets check the forum and see if anyone has rum", would be "Lets check the forum and see if anyone has ****".
Similar to the other answers but this uses \b in regex to match word boundaries (whole words). It also creates the regex-compatible banned list on the fly before passing to preg_replace_callback().
$dn1['title'] = 'access forum';
$banned_names = array('about','access','account','rum');
$banned_list = array_map(function($r) { return '/\b' . preg_quote($r, '/') . '\b/'; }, $banned_names);
$title = preg_replace_callback($banned_list, function($m) {
return $m[0][0].str_repeat('*', strlen($m[0])-1);
}, $dn1['title']);
echo $title; //a***** forum
You can use regex with \W to match a "non-word" character:
var_dump(preg_match('/\Wrum\W/i', 'the forum thing')); // returns 0 i.e. doesn't match
var_dump(preg_match('/\Wrum\W/i', 'the rum thing')); // returns 1 i.e. matches
The preg_replace() method takes an array of filters like str_replace() does, but you'll have to adjust the list to include the pattern delimiters and the \W on both sides. You could store the full patterns statically in your list:
$banlist = ['/\Wabout\W/i','/\Waccess\W/i', ... ];
preg_replace($banlist, '****', $text);
Or adjust the array on the fly to add those bits.
You can use preg_replace() to look for your needles with a beginning/end of string tag after converting each string in your haystack to an array of strings, so you'll be matching on full words. Alternatively you can add spaces and continue to use str_ireplace() but that option would fail if your word is the first or last word in the string being checked.
Adding spaces (will miss first/last word, not reccomended):
You'll have to modify your filtering array first of course. And yes the foreach could be simpler, but I hope this makes clear what I'm doing/why.
foreach($filterWords as $key => $value){
$filterWords[$key] = " ".$value." ";
}
str_ireplace ( $filterWords, "****", $dn1['title'] );
OR
Breaking up long string (recommended):
foreach($filterWords as $key => $value){
$filterWords[$key] = "/^".$value."$/i"; //add regex for beginning/end of string value
}
preg_replace ( $filterWords, "****", explode(" ", $dn1['title']) );
I have an array of words and a string and want to add a hashtag to the words in the string that they have a match inside the array. I use this loop to find and replace the words:
foreach($testArray as $tag){
$str = preg_replace("~\b".$tag."~i","#\$0",$str);
}
Problem: lets say I have the word "is" and "isolate" in my array. I will get ##isolate at the output. this means that the word "isolate" is found once for "is" and once for "isolate". And the pattern ignores the fact that "#isoldated" is not starting with "is" anymore and it starts with "#".
I bring an example BUT this is only an example and I don't want to just solve this one but every other possiblity:
$str = "this is isolated is an example of this and that";
$testArray = array('is','isolated','somethingElse');
Output will be:
this #is ##isolated #is an example of this and that
You may build a regex with an alternation group enclosed with word boundaries on both ends and replace all the matches in one pass:
$str = "this is isolated is an example of this and that";
$testArray = array('is','isolated','somethingElse');
echo preg_replace('~\b(?:' . implode('|', $testArray) . ')\b~i', '#$0', $str);
// => this #is #isolated #is an example of this and that
See the PHP demo.
The regex will look like
~\b(?:is|isolated|somethingElse)\b~
See its online demo.
If you want to make your approach work, you might add a negative lookbehind after \b: "~\b(?<!#)".$tag."~i","#\$0". The lookbehind will fail all matches that are preceded with #. See this PHP demo.
A way to do that is to split your string by words and to build a associative array with your original array of words (to avoid the use of in_array):
$str = "this is isolated is an example of this and that";
$testArray = array('is','isolated','somethingElse');
$hash = array_flip(array_map('strtolower', $testArray));
$parts = preg_split('~\b~', $str);
for ($i=1; $i<count($parts); $i+=2) {
$low = strtolower($parts[$i]);
if (isset($hash[$low])) $parts[$i-1] .= '#';
}
$result = implode('', $parts);
echo $result;
This way, your string is processed only once, whatever the number of words in your array.
Here is my problem:
Using preg_replace('#\b(word)\b#','****',$text);
Where in text I have word\word and word, the preg_replace above replaces both word\word and word so my resulting string is ***\word and ***.
I want my string to look like : word\word and ***.
Is this possible? What am I doing wrong???
LATER EDIT
I have an array with urls, I foreach that array and preg_replace the text where url is found, but it's not working.
For instance, I have http://www.link.com and http://www.link.com/something
If I have http://www.link.com it also replaces http://www.link.com/something.
You are effectively specifying that you don't want certain characters to count as word boundary. Therefore you need to specify the "boundaries" yourself, something like this:
preg_replace('#(^|[^\w\\])(word)([^\w\\]|$)#','**',$text);
What this does is searches for the word surrounded by line boundaries or non-word characters except the back slash \. Therefore it will match .word, but not .word\ and not `\word. If you need to exclude other characters from matching, just add them inside the brackets.
You could just use str_replace("word\word", "word\word and"), I dont really see why you would need to use a preg_replace in your case given above.
Here is a simple solution that doesn't use a regex. It will ONLY replace single occurances of 'word' where it is a lone word.
<?php
$text = "word\word word cat dog";
$new_text = "";
$words = explode(" ",$text); // split the string into seperate 'words'
$inc = 0; // loop counter
foreach($words as $word){
if($word == "word"){ // if the current word in the array of words matches the criteria, replace it
$words[$inc] = "***";
}
$new_text.= $words[$inc]." ";
$inc ++;
}
echo $new_text; // gives 'word\word *** cat dog'
?>
I am using preg_replace($oldWords, $newWords, $string); to replace an array of words.
I wish to replace all words starting with foo into hello, and all words starting with bar into world
i.e foo123 should change to hello , foobar should change to hello, barx5 should change to world, etc.
If my arrays are defined as:
$oldWords = array('/foo/', '/bar/');
$newWords = array('hello', 'world');
then foo123 changes to hello123 and not hello. similarly barx5 changes to worldx5 and not world
How do I replace the complete matched word?
Thanks.
This is actually pretty simple if you understand regex, as well as how preg_replace works.
Firstly, your replacement arrays are incorrectly formed. What is:
$oldWords = array('\foo\', '\bar\');
Should instead be:
$oldWords = array('/foo/', '/bar/');
As the backslash in php escapes the character after it, meaning your strings were getting turned into non-strings, and it was messing up the rest of your code.
As to your actual question, however, you can achieve the desired effect with this:
$oldWords = array('/foo\w*/', '/bar\w*/');
\w matches any word character, while * is a quantifier either meaning 0 or any number of matches.
Adding in those two items will cause the regex to match any string with foo and x number of word-characters directly after it, which is what preg_replace then replaces; the match.
one way to do it is to loop through the array checking each word, since we are only checking the first three letters I would use a substr() instead of a regex because regex functions are slower.
foreach( $oldWords as $word ) {
$newWord = substr( $word, 0, 2 );
if( $newWord === 'foo' ) {
$word = 'hello';
}
else if( $newWord === 'bar' ) {
$word = 'world';
}
};
I have a string that has the following structure:
ABC_ABC_PQR_XYZ
Where PQR has the structure:
ABC+JKL
and
ABC itself is a string that can contain alphanumeric characters and a few other characters like "_", "-", "+", "." and follows no set structure:
eg.qWe_rtY-asdf or pkl123
so, in effect, the string can look like this:
qWe_rtY-asdf_qWe_rtY-asdf_qWe_rtY-asdf+JKL_XYZ
My goal is to find out what string constitutes ABC.
I was initially just using
$arrString = explode("_",$string);
to return $arrString[0] before I was made aware that ABC ($arrString[0]) itself can contain underscores, thus rendering it incorrect.
My next attempt was exlpoding it on "_" anyway and then comparing each of the exploded string parts with the first string part until I get a semblance of a pattern:
function getPatternABC($string)
{
$count = 0;
$pattern ="";
$arrString = explode("_", $string);
foreach($arrString as $expString)
{
if(strcmp($expString,$arrString[0])!==0 || $count==0)
{
$pattern = $pattern ."_". $arrString[$count];
$count++;
}
else break;
}
return substr($pattern,1);
}
This works great - but I wanted to know if there was a more elegant way of doing this using regular expressions?
Here is the regex solution:
'^([a-zA-Z0-9_+-]+)_\1_\1\+'
What this does is match (starting from the beginning of the string) the longest possible sequence consisting of the characters inside the square brackets (edit that per your spec). The sequence must appear exactly twice, each time followed by an underscore, and then must appear once more followed by a plus sign (this is actually the first half of PQR with the delimiter before JKL). The rest of the input is ignored.
You will find ABC captured as capture group 1.
So:
$input = 'qWe_rtY-asdf_qWe_rtY-asdf_qWe_rtY-asdf+JKL_XYZ';
$result = preg_match('/^([a-zA-Z0-9_+-]+)_\1_\1\+/', $input, $matches);
if ($result) {
echo $matches[2];
}
See it in action.
Sure, just make a regular expression that matches your pattern. In this case, something like this:
preg_match('/^([a-zA-Z0-9_+.-]+)_\1_\1\+JKL_XYZ$/', $string, $match);
Your ABC is in $match[1].
If the presence of underscores in these strings has a low frequency, it may be worth checking to see if a simple explode() will do it before bothering with regex.
<?php
$str = 'ABC_ABC_PQR_XYZ';
if(substr_count($str, '_') == 3)
$abc = reset(explode('_', $str));
else
$abc = regexy_function($str);
?>