什么是优雅编程？什么是优雅代码？

个人理解：所谓优雅编程就是喝着咖啡，摸着键盘，想着业务；优雅代码的定义是：1、尽可能的少单双引号；2、不要嵌套；3、命名全是最基本的英语单词；4、代码像英文一样，是一段一段的；5、一个应用代码组织调理清晰，最好是树关系，网关系少用。下边是一个sql查询的连贯操作实现方法，请大家指导指导！/*** DB连贯操作、sql条件构造* From: EQPHP FrameWork* Author: art_youth* E-mail: 258122391@qq.com* Pub data: 2012-11-09*/class query{public $sql='';public $option=array();static $keyword=array('select','from','where','group','having','order','limit');//初始化查询参数function __construct($table,$prefix=''){$this->option['from']=$prefix.$table;}//构造参数function __call($method,$param){if (in_array($method,self::$keyword)) {$this->option[$method]=$param[0];return $this;}}//输出查询结果function out($mode='sql',$rs_count=0,$now_page=1,$page_size=20){$this->sql='';foreach (self::$keyword as $key) {$value=($key == 'group' || $key == 'order') ? $key.' by' : $key;if ($key === 'where' && is_array($this->option['where'])) {$this->option['where']=self::condition($this->option['where']);}if (isset($this->option[$key]) && trim($this->option[$key])) {$this->sql.=' '.$value.' '.trim($this->option[$key]);}unset($this->option[$key]);}$this->sql=trim($this->sql);switch($mode){case 'rs':return db::rs($this->sql);case 'list':return db::rs_list($this->sql);case 'page':return db::page_list($this->sql,$rs_count,$now_page,$page_size);default:return $this->sql;}}//构造sql查询条件static function condition($data){//处理逻辑连接符$logic=' and ';if (isset($data['logic'])) {$logic=' '.$data['logic'].' ';unset($data['logic']);}//处理字符串(本生sql)if (isset($data['query'])) {$condition[]='('.$data['query'].')';unset($data['query']);}//处理条件数据foreach ($data as $key=>$value) {$condition[]='('.self::parse_expression($key,$value).')';}return implode($logic,$condition);}//解析表达式private static function parse_expression($key,$value){if (is_numeric($value)) return $key.'='.$value;if (is_string($value)) return $key.'="'.$value.'"';if (is_array($value)) {//基本条件查询if (preg_match('/^(eq|neq|gt|egt|lt|elt)$/i',$value[0])) {is_string($value[1]) && $value[1]='"'.$value[1].'"';$operator=array('eq'=>'=','neq'=>'','gt'=>'>','egt'=>'>=','lt'=>'' return $key.$operator[$value[0]].$value[1];}//in范围查找if (in_array($value[0],array('in','not in'))) {is_array($value[1]) && $value[1]=implode(',',$value[1]);return $key.' '.$value[0].'('.$value[1].')';}//between区间查找if (in_array($value[0],array('between','not between'))) {$param=is_string($value[1]) ? explode(',',$value[1]) : $value[1];return $key.' '.$value[0].' '.$param[0].' and '.$param[1];}//like模糊匹配if (in_array($value[0],array('like','not like'))) {if (is_array($value[1])) {$buffer=array();foreach ($value[1] as $param) {$buffer[]=$key.' '.$value[0].' "'.$param.'"';}$logic=isset($value[2]) ? ' '.$value[2].' ' : ' or ';return implode($logic,$buffer);}if (strpos($key,'|') !== false) {$buffer=array();foreach (explode('|',$key) as $field) {$buffer[]='('.$field.' '.$value[0].' "'.$value[1].'")';}return implode(' or ',$buffer);}if (strpos($key,'&') !== false) {$buffer=array();foreach (explode('&',$key) as $field) {$buffer[]='('.$field.' '.$value[0].' "'.$value[1].'")';}return implode(' and ',$buffer);}return $key.' '.$value[0].' "'.$value[1].'"';}//数学区间查询(1,9)/[2,3)if ($value[0] === 'extent') {$logic=isset($value[2]) ? ' '.$value[2].' ' : ' && ';$operator=array('('=>'>','['=>'>=',')'=>'' preg_match('/^(\(|\[)(.*),(.*)(\)|\])$/',$value[1],$param);$result='';isset($param[2]) && $result.=$key.$operator[$param[1]].$param[2];isset($param[4]) && $result.=$logic.$key.$operator[$param[4]].$param[3];return $result;}return '';}}//资源回收function __destruct(){unset($this->option,$this->sql);}}复制代码