What is elegant programming? What is elegant code?-PHP Tutorial-php.cn

What is elegant programming? What is elegant code?

WBOY

Release： 2016-07-25 08:48:56

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Personal understanding:
The so-called elegant programming means drinking coffee, touching the keyboard, and thinking about business;
The definition of elegant code is:
1. Use as few single and double quotation marks as possible;
2. Do not nest;
3. Full naming It is the most basic English word;
4. Like English, the code is divided into paragraphs;
5. An application code is clearly organized and organized. It is best to use tree relations and use less network relations.

Below is a method to implement a coherent operation of SQL query. Please give me your guidance!

/**
* DB coherent operation, sql conditional construction
* 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'=>'<','elt'=>'<=',);
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);
}
}

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