preg_replace and possible json issues - php

I need to replace a whitespace at the beginning of any newline. I am using JSON to send over the POST values and suspect this may have something to do with it not working.
$str='
This is a string.
This should be left justified by removing whitespaces preceding it.
';
preg_replace('/^\s+/', '', $str);
Running this, works as expected. When I attempt to use it with my POST array, the whitespaces remain. Why?
Does JSON play a part in this?
EDIT:
Just to clarify, the array being sent over is not JSON encoded, it is a PHP array using JSON POST.
I just tried modifying my regex a bit and can at least verify that preg_replace is doing something. If I do: /\s+/, all spaces are removed. So, I know it's working somewhat.
Is my regex correct?
EDIT #2
This is making me crazy. I figured I would just trim the whitespace in my javascript and call it a day, but I'm getting the same exact result.
Is there any other circumstance that would stop this regex from matching?
/^\s+/

What about this:
$str='
This is a string.
This should be left justified by removing whitespaces preceding it.
';
preg_replace('/^\s+/m', '', $str);
I've just added the m modifier. See http://us3.php.net/manual/en/reference.pcre.pattern.modifiers.php

try this:
foreach($trim_val as $key => $value) {
$trim_val[$key] = trim($value);
}
$json = json_encode($trim_val);
already solution is here given by someone, check

Related

How to get a number from a html source page?

I'm trying to retrieve the followed by count on my instagram page. I can't seem to get the Regex right and would very much appreciate some help.
Here's what I'm looking for:
y":{"count":
That's the beginning of the string, and I want the 4 numbers after that.
$string = preg_replace("{y"\"count":([0-9]+)\}","",$code);
Someone suggested this ^ but I can't get the formatting right...
You haven't posted your strings so it is a guess to what the regex should be... so I'll answer on why your codes fail.
preg_replace('"followed_by":{"count":\d')
This is very far from the correct preg_replace usage. You need to give it the replacement string and the string to search on. See http://php.net/manual/en/function.preg-replace.php
Your second usage:
$string = preg_replace(/^y":{"count[0-9]/","",$code);
Is closer but preg_replace is global so this is searching your whole file (or it would if not for the anchor) and will replace the found value with nothing. What your really want (I think) is to use preg_match.
$string = preg_match('/y":\{"count(\d{4})/"', $code, $match);
$counted = $match[1];
This presumes your regex was kind of correct already.
Per your update:
Demo: https://regex101.com/r/aR2iU2/1
$code = 'y":{"count:1234';
$string = preg_match('/y":\{"count:(\d{4})/', $code, $match);
$counted = $match[1];
echo $counted;
PHP Demo: https://eval.in/489436
I removed the ^ which requires the regex starts at the start of your string, escaped the { and made the\d be 4 characters long. The () is a capture group and stores whatever is found inside of it, in this case the 4 numbers.
Also if this isn't just for learning you should be prepared for this to stop working at some point as the service provider may change the format. The API is a safer route to go.
This regexp should capture value you're looking for in the first group:
\{"count":([0-9]+)\}
Use it with preg_match_all function to easily capture what you want into array (you're using preg_replace which isn't for retrieving data but for... well replacing it).
Your regexp isn't working because you didn't escaped curly brackets. And also you didn't put count quantifier (plus sign in my example) so it would only capture first digit anyway.

Regex for PHP seems simple but is killing me

I'm trying to make a replace in a string with a regex, and I really hope the community can help me.
I have this string :
031,02a,009,a,aaa,AZ,AZE,02B,975,135
And my goal is to remove the opposite of this regex
[09][0-9]{2}|[09][0-9][A-Za-z]
i.e.
a,aaa,AZ,AZE,135
(to see it in action : http://regexr.com?3795f )
My final goal is to preg_replace the first string to only get
031,02a,009,02B,975
(to see it in action : http://regexr.com?3795f )
I'm open to all solution, but I admit that I really like to make this work with a preg_replace if it's possible (It became something like a personnal challenge)
Thanks for all help !
As #Taemyr pointed out in comments, my previous solution (using a lookbehind assertion) was incorrect, as it would consume 3 characters at a time even while substrings weren't always 3 characters.
Let's use a lookahead assertion instead to get around this:
'/(^|,)(?![09][0-9]{2}|[09][0-9][A-Za-z])[^,]*/'
The above matches the beginning of the string or a comma, then checks that what follows does not match one of the two forms you've specified to keep, and given that this condition passes, matches as many non-comma characters as possible.
However, this is identical to #anubhava's solution, meaning it has the same weakness, in that it can leave a leading comma in some cases. See this Ideone demo.
ltriming the comma is the clean way to go there, but then again, if you were looking for the "clean way to go," you wouldn't be trying to use a single preg_replace to begin with, right? Your question is whether it's possible to do this without using any other PHP functions.
The anwer is yes. We can take
'/(^|,)foo/'
and distribute the alternation,
'/^foo|,foo/'
so that we can tack on the extra comma we wish to capture only in the first case, i.e.
'/^foo,|,foo/'
That's going to be one hairy expression when we substitute foo with our actual regex, isn't it. Thankfully, PHP supports recursive patterns, so that we can rewrite the above as
'/^(foo),|,(?1)/'
And there you have it. Substituting foo for what it is, we get
'/^((?![09][0-9]{2}|[09][0-9][A-Za-z])[^,]*),|,(?1)/'
which indeed works, as shown in this second Ideone demo.
Let's take some time here to simplify your expression, though. [0-9] is equivalent to \d, and you can use case-insensitive matching by adding /i, like so:
'/^((?![09]\d{2}|[09]\d[a-z])[^,]*),|,(?1)/i'
You might even compact the inner alternation:
'/^((?![09]\d(\d|[a-z]))[^,]*),|,(?1)/i'
Try it in more steps:
$newList = array();
foreach (explode(',', $list) as $element) {
if (!preg_match('/[09][0-9]{2}|[09][0-9][A-Za-z]/', $element) {
$newList[] = $element;
}
}
$list = implode(',', $newList);
You still have your regex, see! Personnal challenge completed.
Try matching what you want to keep and then joining it with commas:
preg_match_all('/[09][0-9]{2}|[09][0-9][A-Za-z]/', $input, $matches);
$result = implode(',', $matches);
The problem you'll be facing with preg_replace is the extra-commas you'll have to strip, cause you don't just want to remove aaa, you actually want to remove aaa, or ,aaa. Now what when you have things to remove both at the beginning and at the end of the string? You can't just say "I'll just strip the comma before", because that might lead to an extra comma at the beginning of the string, and vice-versa. So basically, unless you want to mess with lookaheads and/or lookbehinds, you'd better do this in two steps.
This should work for you:
$s = '031,02a,009,a,aaa,AZ,AZE,02B,975,135';
echo ltrim(preg_replace('/(^|,)(?![09][0-9]{2}|[09][0-9][A-Za-z])[^,]+/', '', $s), ',');
OUTPUT:
031,02a,009,02B,975
Try this:
preg_replace('/(^|,)[1-8a-z][^,]*/i', '', $string);
this will remove all substrings starting with the start of the string or a comma, followed by a non allowed first character, up to but excluding the following comma.
As per #GeoffreyBachelet suggestion, to remove residual commas, you should do:
trim(preg_replace('/(^|,)[1-8a-z][^,]*/i', '', $string), ',');

Regex For PHP Code?

I have the following code
<?
php drupal_set_message("Your registration submission has been received.");
drupal_goto("/events-initiatives/events-listing");
?>
And I want to remove everything but the Your registration submission has been received. and this message will change, so I need it to be a wildcard. So it would also make say
<?php
drupal_set_message("Testing!!!");
drupal_goto("/events-initiatives/events-listing");
?>
But I can't figure out how to do the PHP code, my current one is
preg_replace('#(<?php drupal_set_message(").*?("); drupal_goto("/guidelines-resources/professionals/lending-library"); ?>)#', '$1$2', $string);
but that isn't working, it seems to have problems with the ( in it.
Any idea how I could do this?
From looking at your original post, (before your regex was changed into a PHP snippet) I'd suggest you are looking for a regex along these lines:
#<\?php\s+drupal_set_message\(".*?"\);\s+drupal_goto\("/guidelines-resources/professionals/lending-library"\);\s+\?>#
Note that this regex:
escapes all special characters (e.g., ?, ( and )) with preceding slashes
replaces a single space with \s+ which matches one or more consecutive whitespace characters
EDIT
After rereading your question, if the only thing you want left is the text that is passed as an argument to drupal_set_message, then try this:
$pattern = '#\bdrupal_set_message\("(.*?)"\)#';
$found = preg_match($pattern, $subject, $matches);
// if found, $matches[1] will contain the argument to drupal_set_message
You can escape the special characters (though really, just the open and close parentheses) with backslashes. On a side note, if you have a decent IDE then it should have sophisticated regex-capable search-and-replace; use it (although if you do, you'll probably need to also escape the forward slashes, as those are the most likely delimiters that your IDE would use).

Problem using regex to remove number formatting in PHP

I'm having this issue with a regular expression in PHP that I can't seem to crack. I've spent hours searching to find out how to get it to work, but nothing seems to have the desired effect.
I have a file that contains lines similar to the one below:
Total','"127','004"','"118','116"','"129','754"','"126','184"','"129','778"','"128','341"','"127','477"','0','0','0','0','0','0
These lines are inserted into INSERT queries. The problem is that values like "127','004" are actually supposed to be 127,004, or without any formatting: 127004. The latter is the actual value I need to insert into the database table, so I figured I'd use preg_replace() to detect values like "127','004" and replace them with 127004.
I played around with a Regular Expression designer and found that I could use the following to get my desired results:
Regular Expression
"(\d+)','(\d{3})"
Replace Expression
$1$2
The line on the top of this post would end up like this: (which is what I am after)
Total','127004','118116','129754','126184','129778','128341','127477','0','0','0','0','0','0
This, however, does not work in PHP. Nothing is being replaced at all.
The code I am using is:
$line = preg_replace("\"(\d+)','(\d{3})\"", '$1$2', $line);
Any help would be greatly appreciated!
There are no delimiters in your regex. Delimiters are required in order for PHP to know what is the pattern to match and what is a pattern modifier (e.g. i - case-insensitive, U - ungreedy, ...). Use a character that doesn't occur in your pattern, typically you'll see a slash '/' used.
Try this:
$line = preg_replace("/\"(\d+)','(\d{3})\"/", '$1$2', $line);
You forgot to wrap your regular expression in front-slashes. Try this instead:
"/\"(\d+)','(\d{3})\"/"
use preg_replace("#\"(\d+)','(\d+)\"#", '$1$2', $s); instead of yours

PHP trim problem

I asked earlier how can I get rid of extra hyphens and whitespace added at the end and beginning of user submitted text for example, -ruby-on-rails- should be ruby-on-rails you guys suggested trim() which worked fine by itself but when I added it to my code it did not work at all it actually did some funky things to my code.
I tried placing the trim() code every where in my code but nothing worked can someone help me to get rid of extra hyphens and whitespace added at the end and beginning of user submitted text?
Here is my PHP code.
$tags = preg_split('/,/', strip_tags($_POST['tag']), -1, PREG_SPLIT_NO_EMPTY);
$tags = str_replace(' ', '-', $tags);
Update the trim statement to the following in order to update each item in the array:
foreach($tags as $key=>$value) {
$tags[$key] = trim($value, '-');
}
That should allow you to trim each value based on a string being expected.
If you have a string you can do this to strip hyphens from the beginning and end:
$tag = trim($tag, '-');
Your problem is that preg_split returns an array, but trim takes a string. You need to do the above for every string in the array.
Regarding trimming whitespace: if you are first converting all whitespace to hyphens then it should not be necessary to trim whitespace afterwards - the whitespace will already be gone. But be careful because the terms "whitespace" and "space" have different meanings. Your question seems to muddle these two terms.
Verify that the hyphen character you're attempting to trim is the same hyphen character that is wrapping -ruby-on-rails-. For example, these are all different characters that look similar: -, –, —, ―.
Im new to StackOverflow.com so I hope the function I wrote helps you in some way. You can specify what characters you want it to trim in the second parameter, for your example I've set it to just remove whitespace and 'dashes' by default, i've tested it using 'ruby-on-rails' and a somewhat extreme example of '- -- - - ruby-on-rails - -- - - -' and both produce the result: 'ruby-on-rails'.
The regular expression might be a bit of a q&d way of going about it but I hope it helps you, just reply if you have any problems implementing it or w/e.
function customTrim($s,$c='- ')
{
preg_match('#'.($a='[^'.$c.']').'.{1,}'.$a.'#',$s,$match);
return $match[0];
}

Categories