$re = '/(?<searched_type>(index|source|sourcetype))(?:\W+)(?<searched_value>\S[^\s|\||\"]+)/m';
$str = 'search index="application_sec_pr_secure"|delete
search index = application_sec_pr secure sourcetype=aaa | delete
search index=infra_aaa_summary* sourcetype=aaa | delete
search * sourcetype=aaa | delete';
preg_match_all($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