CODEWITHSUNDEEP
regex
Max
Max

Reputation: 121

Regex match multiple occurrences of same pattern

I'm trying to run a test to see if a long string with multiple lines has multiple occurrences of the same pattern, or lets say 5 or 10 occurrences.

So a string like:

$string = "this is a test pattern1 more of a test pattern1

and so on and so on pattern1";

So in this case I was trying in PHP:

if (preg_match('/(pattern1)\1{2,}/m',$string)) print "Found 2+ occurrences of pattern1\n";

Of course this does not work.

And I cannot use preg_match_all.

Can someone correct my regex please?

Upvotes: 7

Views: 13741

Answers (4)

sathya_dev
sathya_dev

Reputation: 513

Check this pattern 

/(pattern1)/g

g - modifier finds all matches instead of returning first match.

Upvotes: 1

aelor
aelor

Reputation: 11126

why dont you simply search for the word/pattern using preg_match_all and count the number of occurences :

<?php
$message="this is a test pattern1 more of a test pattern1 and one more pattern1";
echo preg_match_all('/pattern1/i', $message, $matches);

will return 3.

or rather in your case:

<?php
$message="this is a test pattern1 more of a test pattern1 and one more pattern1";
if(preg_match_all('/pattern1/i', $message, $matches) >= 2 ) print "Found 2+ occurences of pattern1\n";

Upvotes: 0

hwnd
hwnd

Reputation: 70742

You can use the following..

if (preg_match('/(pattern1)(?:((?!\1).)*\1){2,}/s', $string)) {

Working Demo

Upvotes: 1

Casimir et Hippolyte
Casimir et Hippolyte

Reputation: 89629

If I understand well, you was not far from the good pattern (for three occurrences here):

/(pattern1)(?:.*?\1){2,}/s

where the s modifier allows the dot to match newlines.

Upvotes: 3

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