Php Regular Expression repeated characters

Question

I have a string in php like this.

$str = \"ABCCCDE\" //Contains repeated character CCC more than 2 times

I want to know if there is any repeated characters

Answer 1

if (preg_match('/(.)\\1{2}/', $str))
   echo "Has 3 same characters consecutively!";

The (.) will match any character (except new lines), and the \1 will match a pattern same as the first matched group — in this case, the character we've just matched. So this RegEx will match 3 same consecutive characters.

Answer 2

You can use:

'/(.)\1\1/'

E.g.:

preg_match('/(.)\1\1/', $str, $matches);