PHP trim entire words - php

How to trim entire words from php string
like I dont want "foo", "bar", "mouse" words on left and "killed" on the end of string.
So "fo awesome illed" would not be trimmed
But "foo awesome killed" => " awesome "
"killed awesome foo" not trimmed (killed trimmed from right, rest from left)
When I'm using ltrim($str, "foo"); it will trim any letter from "foo" - "f" or "o"

Use preg_replace() to replace the strings with an empty string.
$str = preg_replace('/^(foo|bar|mouse)|killed$/', '', $str);
Go to regular-expressions.info to learn more about regexp.

str_replace($replaceme, $withme, $here) works much faster (and is easier) if you dont need advanced regex features.
If you know the exact word you are looking for ($replaceme) and you want to delete it you can just use "" (empty string) in the $withme parameter.

Use preg_match function and create your own patteren based on your requirment.
<?php
$subject = "abcdef";
$pattern = '/^foo$killed/';
preg_match($pattern, $subject, $matches, PREG_OFFSET_CAPTURE, 3);
print_r($matches);
?>

Related

Replace multiple items in a string

i've scraped a html string from a website. In this string it contains multiple strings like color:#0269D2. How can i make str_replace code which replace this string with another color ?
For instance something like this just looping through all color:#0269D in the fulltext string variable?
str_replace("color:#0269D","color:#000000",$fulltext);
you pass array to str_replace function , no need to use loop
$a= array("color:#0269D","color:#000000");
$str= str_replace($a,"", $string);
You have the right syntax. I would add a check:
$newText = str_replace("color:#0269D", "color:#000000", $fulltext, $count);
if($count){
echo "Replaced $count occurrences of 'color'.";
}
This code might be too greedy for what you're looking to do. Careful. Also if the string differs at all, for example color: #0269D, this replacement will not happen.
’str_replace’ already replaces all occurrences of the search string with the replacement string.
If you want to replace all colors but aren't sure which hexcodes you'll find you could use preg_replace to match multiple occurrences of a pattern with a regular expression and replace it.
In your case:
$str = "String with loads of color:#000000";
$pattern = '/color ?: ?#[0-9a-f]{3,6}/i';
$replacement = "color:#FFFFFF";
$result = preg_replace($pattern, $replacement, $str);

Cut string from end to specific char in php

I would like to know how I can cut a string in PHP starting from the last character -> to a specific character. Lets say I have following link:
www.whatever.com/url/otherurl/2535834
and I want to get 2535834
Important note: the number can have a different length, which is why I want to cut out to the / no matter how many numbers there are.
Thanks
In this special case, an url, use basename() :
echo basename('www.whatever.com/url/otherurl/2535834');
A more general solution would be preg_replace(), like this:
<----- the delimiter which separates the search string from the remaining part of the string
echo preg_replace('#.*/#', '', $url);
The pattern '#.*/#' makes usage of the default greediness of the PCRE regex engine - meaning it will match as many chars as possible and will therefore consume /abc/123/xyz/ instead of just /abc/ when matching the pattern.
Use
explode() AND end()
<?php
$str = 'www.whatever.com/url/otherurl/2535834';
$tmp = explode('/', $str);
echo end ($tmp);
?>
Working Demo
This should work for you:
(So you can get the number with or without a slash, if you need that)
<?php
$url = "www.whatever.com/url/otherurl/2535834";
preg_match("/\/(\d+)$/",$url,$matches);
print_r($matches);
?>
Output:
Array ( [0] => /2535834 [1] => 2535834 )
With strstr() and str_replace() in action
$str = 'www.whatever.com/url/otherurl/2535834';
echo str_replace("otherurl/", "", strstr($str, "otherurl/"));
strstr() finds everything (including the needle) after the needle and the needle gets replaced by "" using str_replace()
if your pattern is fixed you can always do:
$str = 'www.whatever.com/url/otherurl/2535834';
$tmp = explode('/', $str);
echo $temp[3];
Here's mine version:
$string = "www.whatever.com/url/otherurl/2535834";
echo substr($string, strrpos($string, "/") + 1, strlen($string));

How to find which string occuring first in text among multiple strings?

I have text like this, "wow! It's Amazing.". I need to split this text by either "!" or "." operator and need to show the first element of array(example $text[0]).
$str="wow! it's, a nice product.";
$text= preg_split('/[!.]+/', $str);
here $text[0] having the value of "wow" only. but I want to know which string occurring first in text (whether its "!" or "."), so that I will append it to $text[0] and shown like this "wow!".
I want to use this preg_split in smarty templates.
<p>{assign var="desc" value='/[!.]+/'|preg_split:'wow! it's, a nice product.'}
{$desc[0]}.</p>
the above code displays the result as "wow". There is no preg_match in smarty, so far i have searched.other wise,i would use that.
Any help would be appreciated.Thanks in Advance.
Instead of preg_split you should use preg_match:
$str="wow! it's, a nice product.";
if ( preg_match('/^[^!.]+[!.]/', $str, $m) )
$s = $m[0]; //=> wow!
If you must use preg_split only then you can do:
$arr = preg_split('/([^!.]+[!.])/', $str, -1, PREG_SPLIT_DELIM_CAPTURE|PREG_SPLIT_NO_EMPTY);
$s = $arr[0]; //=> wow!
Try this
/(.+[!.])(.+)/
it will split the string in to two.
$1 => wow!
$2 => it's, a nice product.
see here

preg_replace() seems to remove entire word instead of part of it

I'm trying to match a certain word and replace part of the word with certain text but leave the rest of the word intact. It is my understanding that adding parentheses to part of the regex pattern means that the pattern match within the parentheses gets replaced when you use preg_replace()
for testing purposes I used:
$text = 'batman';
echo $new_text = preg_replace('#(bat)man#', 'aqua', $text);
I only want 'bat' to be replaced by 'aqua' to get 'aquaman'. Instead, $new_text echoes 'aqua', leaving out the 'man' part.
preg_replace replaces all the string matched by regular expression
$text = 'batman';
echo $new_text = preg_replace('#bat(man)#', 'aqua\\1', $text);
Capture man instead and append it to your aqua prefix
Another way of doing that is to use assertions:
$text = 'batman';
echo $new_text = preg_replace('#bat(?=man)#', 'aqua', $text);
I would not use preg_* functions for this and just do str_replace() DOCs:
echo str_replace('batman', 'aquaman', $text);
This is simpler as a regex is not really needed in this case. Otherwise it would be with a regular expression:
echo $new_text = preg_replace('#bat(man)#', 'aqua\\1', $text);
This will substitute your man in after aqua when replacing the entire search phrase. preg_replace DOCs replaces the entire matching portion of the pattern.
The way you're trying to do it, it would be more like:
preg_replace('#bat(man)#', 'aqua$1', $text);
I'd using positive lookahead:
preg_replace('/bat(?=man)/', 'aqua', $text)
Demo here: http://ideone.com/G9F4q
The brackets are creating a capturing group, that means you can access the part matched by this group using \1.
you can do either what zerkms suggested or use a lookahead that does just check but not match.
$text = 'batman';
echo $new_text = preg_replace('#bat(?=man)#', 'aqua', $text);
This will match "bat" but only if it is followed by "man", and only "bat" is replaced.

Replace after a needle in a string?

I have a string, something like
bbbbabbbbbccccc
Are there any way for me to replace all the letters "b" after the only one letter "a" into "c" without having to split the string, using PHP?
bbbbacccccccccc
odd question.
echo preg_replace('/a(.*)$/e', "'a'.strtr($1, 'b', 'c')", 'bbbabbbbbccccc');
preg_replace matches everything to the right of 'a' with regex. the e modifier in the regex evaluates the replacement string as code. the code in the replacement string uses strtr() to replace 'b's with 'c's.
Here are three options.
First, a split. Yes, I know you want to do it without a split.
$string = 'bbbbabbbbbccccc';
$parts = preg_split('/(a)/', $string, 2, PREG_SPLIT_DELIM_CAPTURE);
// Parts now looks like:
// array('bbb', 'a', 'bbbbcccc');
$parts[2] = str_replace('b', 'c', $parts[2]);
$correct_string = join('', $parts);
Second, a position search and a substring replacement.
$string = 'bbbbabbbbbccccc';
$first_a_index = strpos($string, 'a');
if($first_a_index !== false) {
// Now, grab everything from that first 'a' to the end of the string.
$replaceable = substr($string, $first_a_index);
// Replace it.
$replaced = str_replace('b', 'c', $replaceable );
// Now splice it back in
$string = substr_replace($string, $replaced, $first_a_index);
}
Third, I was going to post a regex, but the one dqhendricks posted is just as good.
These code examples are verbose for clarity, and can be reduced to one-or-two-liners.
$s = 'bbbbabbbbbccccc';
echo preg_replace('/((?:(?!\A)\G|(?<!a)a(?!a))[^b]*)b/', '$1c', $s);
\G matches the position where the previous match ended. On the first match attempt, \G matches the beginning of the string like \A. We don't want that, so we use (?!\A) to prevent it.
(?<!a)a(?!a) matches an a that's neither preceded nor followed by an a. The a is captured in group #1 so we can plug it back into the replacement with $1.
This is a "pure regex" solution, meaning it does the whole job in one call to preg_replace and doesn't rely on embedded code and the /e modifier. It's good to know in case you ever find yourself working within those constraints, but it definitely shouldn't be your first resort.

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