/** * Compare two strings in the same way as strcmp() except that lowercase come before uppercase letters * @param string $str1 First string value for the comparison * @param string $str2 Second string value for the comparison * @return integer */ private function strcmpLowercaseFirst($str1, $str2) { $inversedStr1 = PHPExcel_Shared_String::StrCaseReverse($str1); $inversedStr2 = PHPExcel_Shared_String::StrCaseReverse($str2); return strcmp($inversedStr1, $inversedStr2); }