$re = '/{[^{]*/ms';
$str = '{ABC}
+ 1
- 1
{DEF}
+ 2
- 2
{IJK}
+ 3
- 3
{LMN}
+ 4
- 4
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php