php 返回数据格式化类

<?php 
/** 返回数据格式化类
*   Date:   2011-08-15
*   Author: fdipzone
*   Edit: www.jbxue.com
*/ 
 
class DataReturn{   // class start 
 
    private $type; 
    private $xmlroot; 
    private $callback; 
    private $returnData; 
 
    public function __construct($param=array()){ 
        $this->type = $this->exists($param,'type')? strtoupper($param['type']) : 'JSON';      // 类型 JSON,XML,CALLBACK,ARRAY 
        $this->xmlroot = $this->exists($param,'xmlroot')? $param['xmlroot'] : 'xmlroot';      // xml root dom name 
        $this->callback = $this->exists($param,'callback')? $param['callback'] : '';          // JS callback function name 
 
        $format = array(); 
        $format['retcode'] = $this->exists($param,'format.retcode')? $param['format']['retcode'] : 'retcode';//retcode 对应名称 
        $format['msg'] = $this->exists($param,'format.msg')? $param['format']['msg'] : 'msg';                //msg 对应名称 
        $format['data'] = $this->exists($param,'format.data')? $param['format']['data'] : 'data';            //data 对应名称 
 
        $result = array(); 
        $result[$format['retcode']] = $this->exists($param,'retcode')? $param['retcode'] : 0; 
        $result[$format['msg']] = $this->exists($param,'msg')? $param['msg'] : ''; 
        $result[$format['data']] = $this->exists($param,'data')? $param['data'] : ''; 
 
        $this->returnData = $result; 
    }
 
    //输出数据 
    public function data_return(){ 
        ob_clean(); 
        switch($this->type){ 
            case 'JSON': 
                $this->json_return(); 
                break; 
            case 'XML': 
                $this->xml_return(); 
                break; 
            case 'CALLBACK': 
                $this->callback_return(); 
                break; 
            case 'ARRAY': 
                $this->array_return(); 
                break; 
            default: 
                $this->json_return(); 
        } 
        exit(); 
    }    
    //输出JSON格式数据,如有callback參數則返回JSONP格式 
    private function json_return(){ 
        header('content-type:text/html;charset=utf-8'); 
        if(empty($this->callback)){ 
            echo json_encode($this->returnData); 
        }else{ 
            echo $this->callback.'('.json_encode($this->returnData).');'; 
        } 
    }  
    //输出XML格式数据 
    private function xml_return(){ 
        header('content-type:text/xml;charset=utf-8'); 
        echo $this->xml_encode($this->returnData,$this->xmlroot); 
    }      
    //输出JSON格式数据，并調用callback方法 
    private function callback_return(){ 
        header('content-type:text/html;charset=utf-8'); 
        $this->callback = empty($this->callback)? 'callback' : $this->callback; 
        echo "<script type=\"text/javascript\">\r\n"; 
        echo $this->callback."(".json_encode($this->returnData).");\r\n"; 
        echo "</script>"; 
    }    
    //输出數組格式数据 
    private function array_return(){ 
        header('content-type:text/html;charset=utf-8'); 
        echo '<pre>'; 
        print_r($this->returnData); 
        echo '</pre>'; 
    }  
 
    //XML編碼 
    private function xml_encode($data, $root='xmlroot', $encoding='utf-8') { 
        $xml = "<?xml version=\"1.0\" encoding=\"" . $encoding . "\"?>\n"; 
        $xml.= "<" . $root . ">\n"; 
        $xml.= $this->data_to_xml($data); 
        $xml.= "</" . $root . ">"; 
        return $xml; 
    }    
    //數組轉XML格式 
    private function data_to_xml($data) { 
        if (is_object($data)) { 
            $data = get_object_vars($data); 
        } 
        $xml = ''; 
        foreach ($data as $key => $val) { 
            is_numeric($key) && $key = "item id=\"$key\""; 
            $xml.="<$key>"; 
            $xml.= ( is_array($val) || is_object($val)) ? $this->data_to_xml($val) : $this->cdata($val); 
            list($key, ) = explode(' ', $key); 
            $xml.="</$key>\n"; 
        } 
        return $xml; 
    }    
    //判斷数据是否存在 
    private function exists($obj,$key=''){ 
        if($key==''){ 
            return isset($obj) && !empty($obj); 
        }else{ 
            $keys = explode('.',$key); 
            for($i=0,$max=count($keys); $i<$max; $i++){ 
                if(isset($obj[$keys[$i]])){ 
                    $obj = $obj[$keys[$i]]; 
                }else{ 
                    return false; 
                } 
            } 
            return isset($obj) && !empty($obj); 
        } 
    }  
    //判斷是否需要加上<![CDATA[]]>標記 
    private function cdata($val){ 
        if(!empty($val) && !preg_match('/^[A-Za-z0-9+$]/',$val)){ 
            $val = '<![CDATA['.$val.']]>'; 
        } 
        return $val; 
    } 
 
}   // class end 
?>

<? 
    require_once('DataReturn.class.php'); 
 
    $param = array( // DataReturn 參數 
                    'type'    => 'JSON', // 输出的类型 JSON,XML,CALLBACK,ARRAY 默認為 JSON 
                    'retcode' => '1000', // retcode 的值，默認為0 
                    'msg'     => '',     // msg 的值，默認為空 
                    'data'    => array(  // 要输出的数据 
                                    'id'     => '100', 
                                    'name'   => 'fdipzone', 
                                    'gender' => 1, 
                                    'age'    => 28 
                                 ), 
                    'format'  => array(  // 输出的数据key格式,默認為 retcode,msg,data 
                                    'retcode' => 'status', 
                                    'msg'     => 'info', 
                                    'data'    => 'result' 
                                 ), 
                    'xmlroot'  => 'xmlroot',  // 当type=XML時,XML根節點名稱，默認為xmlroot 
                    'callback' => 'callback'  /* 回調方法名稱
                                                   type=JSON時，默認為空，如不為空，則输出callback({data});
                                                   type=CALLBACK時,默認為callback，自動調用頁面JS回調方法
                                              */ 
    ); 
 
    $obj = new DataReturn($param);  // 创建DataReturn类對象 
    $obj->data_return();            // 按格式输出数据 
?>