php regex error preg_match(): Unknown modifier '['

Question

Iam very new to Php Regex, but somehow learned bit and tried as below, but getting error as : PHP Warning: preg_match(): Unknown modifier '[' in /home/3ZZyLt/prog.php on line 4

Here is the whole code with output: https://ideone.com/fTIyUK

Same code from above link:

<?php 
$email = "paulw Paul Walker paulw 2014-12-28 07:18:09 paul@comp.com 2014-12-28 07:18:09 2014-12-28 07:18:09"; // Invalid email address 
$regex = "/[a-z] [A_Z] [A-Z] [A-Z] (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2}) /[-0-9a-zA-Z.+_]+@[-0-9a-zA-Z.+_]+\.[a-zA-Z]{2,4} (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2}) (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2})/"; 
if ( preg_match( $regex, $email ) ) {
     echo $email . " is a valid email. We can accept it.";
} else { 
     echo $email . " is an invalid email. Please try again.";
} 
?>

Please tell me what needs to be changed?

Updated:

Input: string(a-z) string(a-zA-Z) string(a-zA-Z) string(a-z) date(yyyy-mm-dd hh:mm:ss) emailid date(yyyy-mm-dd hh:mm:ss) date(yyyy-mm-dd hh:mm:ss)

8 Parameters:

userid (string)   
first name(string)  
last name(string)  
userid(string)  
date  
email
date
date

That's horrible regex to begin with, and not going to work as expected anyway. Why not split on spaces first? It's a space-delimited log/whatever line, isn't it? — mario, May 28 '15 at 16:13
The first four groups only capture one single character. This won't work even if the error goes away. — Luceos, May 28 '15 at 16:19
[if you're trying to validate an email, you could use filter_var()](http://stackoverflow.com/questions/19522092/should-i-use-filter-var-to-validate-email) — castis, May 28 '15 at 16:19
Is this whole regex to validate an email? Why not `.*?\s+(\S+@\S+?)\s.*` — chris85, May 28 '15 at 16:20
Perhaps you could explain why you need to do it this way as opposed to using filter_var()? — Kirk Powell, May 28 '15 at 16:30
@Luceos Could you please modify my regex code and make it work? Actually i really didnt understood how to write a better way. — user3815806, May 28 '15 at 16:48

score 1 · Accepted Answer · edited May 25 '16 at 12:21

1

$regex = "/[a-z] [A_Z] [A-Z] [A-Z] (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2}) /[-0-9a-zA-Z.+_]+@[-0-9a-zA-Z.+_]+\.[a-zA-Z]{2,4} (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2}) (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2})/";

If you see this regex closely you have an unescaped / in the middle of regex but you're using / as regex delimiter.

Use this regex instead with an alternative regex delimiter:

$regex = "~[a-z]+ [A-Z]+ [A-Z]+ [A-Z]+ (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2}) [-\w.+]+@[-\w.+]+\.[a-zA-Z]{2,4} (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2}) (\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}):(\d{2})~i";

RegEx Demo

edited May 25 '16 at 12:21

Fabian N.

3,807
2
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answered May 28 '15 at 16:08

anubhava

761,203
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569
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hi, i tried your regex, now getting output as 'invalid', here: https://ideone.com/fTIyUK – user3815806 May 28 '15 at 16:21
1

I didn't alter your regex, it is same. I just changed the regex delimiter. Will check your ideone code – anubhava May 28 '15 at 16:24
Could you please modify my regex code and make it work? – user3815806 May 28 '15 at 16:49
If you can update your question with some valid and invalid input sample data then it will be much easier for me to understand and suggest a fix. – anubhava May 28 '15 at 16:55
I updated input parameters in my post, could you please look into. and many thanks for trying to help me out. :) – user3815806 May 28 '15 at 17:20

php regex error preg_match(): Unknown modifier '['

1 Answers1