Warning: preg_match(): Unknown modifier in PHP

Question

This is my first try at regex in PHP. I would like to use regex in PHP to match sentences that contains two set of words. I have tested it like below but it's not working

$regex= (red|green|round|sweet)[^.]*(apple|apples)    
$sentence = "I have two red apples."

if(preg_match($regex, $sentence)) 
{
    echo 'MATCH!!!';
} else {
    echo 'No MATCH!!!';
}

I am getting an error message in PHP.

Warning: preg_match(): Unknown modifier [

`$regex= "/(red|green|round|sweet)[^.]*(apple|apples)/";` - Plus, if you tested as you said what you posted, should have thrown a parse error to start. — Funk Forty Niner, Oct 30 '14 at 02:51
@Fred-ii- I tested the regex and it works. Just not in php. For some reasons it's complaining about the [ ] — Cryssie, Oct 30 '14 at 02:53
Your posted question is missing semi-colons on two lines, missing quotes and identifier for the first. Which I tested and working. — Funk Forty Niner, Oct 30 '14 at 02:55

score 2 · Answer 1 · answered Oct 30 '14 at 02:56

2

PHP regex must separate character.

$regex = '/(red|green|round|sweet)[^.]*(apple|apples)/';

/ is separate character in this case.

answered Oct 30 '14 at 02:56

alu

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2
7

score 1 · Accepted Answer · answered Oct 30 '14 at 02:58

1

As I said, this is tested and working, where you left out the quotes and identifiers for the first line and missing semi-colons on two lines.

<?php
$regex= "/(red|green|round|sweet)[^.]*(apple|apples)/";
$sentence = "I have two red apples.";

if(preg_match($regex, $sentence))
{
    echo 'MATCH!!!';
} else {
    echo 'No MATCH!!!';
}

answered Oct 30 '14 at 02:58

Funk Forty Niner

74,450
15
68
141

Thank you. I tested the regex separately. I didn't think that all it needs is a "/" in front and back. – Cryssie Oct 30 '14 at 02:59
@Cryssie You're welcome Cryssie. The `/` identifiers are required when executed via PHP. – Funk Forty Niner Oct 30 '14 at 02:59

Warning: preg_match(): Unknown modifier in PHP

2 Answers2