$re = '/.*businessDate(?<businessDate>[^\\\\]*)\\\\u0026closeoutSchemeId\=(?<closeoutSchemeId>[^\\\\]*)\\\\u0026.*positionStateId\=(?<positionStateId>[^\"]*)/';
$str = '{"StatusCode":204,"ReasonPhrase":"No Content","Method":"GET","PathAndQuery":"/api/ibor/v2/positionValuations?businessDate=2017-09-04\\u0026closeoutSchemeId=1\\u0026expand=*\\u0026logicalTimeId=150\\u0026positionStateId=40","MessageType":"Response"}
{"Method":"GET","PathAndQuery":"/api/ibor/v2/positionValuations?businessDate=2017-09-04\\u0026closeoutSchemeId=1\\u0026expand=*\\u0026logicalTimeId=150\\u0026positionStateId=40","MessageType":"Request"}';
preg_match_all($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