<?php /** * TDataFieldAccessor class file * * @author Qiang Xue <qiang.xue@gmail.com> * @link http://www.pradosoft.com/ * @copyright Copyright © 2005-2008 PradoSoft * @license http://www.pradosoft.com/license/ * @version $Id$ * @package System.Util */ /** * TDataFieldAccessor class * * TDataFieldAccessor is a utility class that provides access to a field of some data. * The accessor attempts to obtain the field value in the following order: * - If the data is an array, then the field is treated as an array index * and the corresponding element value is returned; * - If the data is a TMap or TList object, then the field is treated as a key * into the map or list, and the corresponding value is returned. * - If the data is an object, the field is treated as a property or sub-property * defined with getter methods. For example, if the object has a method called * getMyValue(), then field 'MyValue' will retrieve the result of this method call. * If getMyValue() returns an object which contains a method getMySubValue(), * then field 'MyValue.MySubValue' will return that method call result. * * @author Qiang Xue <qiang.xue@gmail.com> * @version $Id$ * @package System.Util * @since 3.0 */ class TDataFieldAccessor { /** * Evaluates the data value at the specified field. * - If the data is an array, then the field is treated as an array index * and the corresponding element value is returned; * - If the data is a TMap or TList object, then the field is treated as a key * into the map or list, and the corresponding value is returned. * - If the data is an object, the field is treated as a property or sub-property * defined with getter methods. For example, if the object has a method called * getMyValue(), then field 'MyValue' will retrieve the result of this method call. * If getMyValue() returns an object which contains a method getMySubValue(), * then field 'MyValue.MySubValue' will return that method call result. * @param mixed data containing the field value, can be an array, TMap, TList or object. * @param mixed field value * @return mixed value at the specified field * @throws TInvalidDataValueException if field or data is invalid */ public static function getDataFieldValue($data,$field) { try { if(is_array($data) || ($data instanceof ArrayAccess)) return $data[$field]; else if(is_object($data)) { if(strpos($field,'.')===false) // simple field { if(property_exists($data,$field)) return $data->{$field}; else return call_user_func(array($data,'get'.$field)); } else // field in the format of xxx.yyy.zzz { $object=$data; foreach(explode('.',$field) as $f) $object=$object->$f; return $object; } } } catch(Exception $e) { throw new TInvalidDataValueException('datafieldaccessor_datafield_invalid',$field,$e->getMessage()); } throw new TInvalidDataValueException('datafieldaccessor_data_invalid',$field); } }