此問題是因為php新版本更新，對函式的支援有改變導致的

解決如下

 $postMedia = array();
       $postMedia['access_token'] = $json->access_token;
       $postMedia['type'] = 'image';

       foreach ($imgs as $img) {
           file_put_contents(CONF_PATH . 'img_' . $img['id'] . '.jpg', file_get_contents($img['pic']));
           //$postMedia['media']=$_SERVER['DOCUMENT_ROOT'].str_replace('http://'.$_SERVER['HTTP_HOST'],'',$img['pic']);
           //$postMedia['media']=$_SERVER['DOCUMENT_ROOT'].str_replace('./','/',CONF_PATH.'img_'.$img['id'].'.jpg');
           // @只支援 5.5以下版本
           //$postMedia['media']=CONF_PATH.'img_'.$img['id'].'.jpg';
//$postMedia['media']=$_SERVER['DOCUMENT_ROOT'].str_replace(array('./'),array('/'),$postMedia['media']);
           $filePath = CONF_PATH . 'img_' . $img['id'] . '.jpg';
           $filePath = $_SERVER['DOCUMENT_ROOT'] . str_replace(array('./'), array('/'), $filePath);
           //CURLFile()只支援php5.6以上版本，
           $postMedia['media'] = new CURLFile($filePath);

           $rt = $this->curlPost('http://file.api.weixin.qq.com/cgi-bin/media/upload?access_token=' . $postMedia['access_token'] . '&type=' . $postMedia['type'], array('media' => $postMedia['media']));

           if ($rt['rt'] == false) {
               $this->error('操作失敗,curl_error:' . $rt['errorno']);
           } else {
               $mediaids .= $rt['media_id'];
               $comma = ',';
           }
       }