5. PDO 数据库封装

<?php
//header('content-type:text/html;charset=utf-8');
class PdoMySQL{
public static $config=array();//设置连接参数，配置信息
public static $link=null;//保存连接标识符
public static $pconnect=false;//是否开启长连接
public static $dbVersion=null;//保存数据库版本
public static $connected=false;//是否连接成功
public static $PDOStatement=null;//保存PDOStatement对象
public static $queryStr=null;//保存最后执行的操作
public static $error=null;//报错错误信息
public static $lastInsertId=null;//保存上一步插入操作产生AUTO_INCREMENT
public static $numRows=0;//上一步操作产生受影响的记录的条数
/**
 * 连接PDO
 * @param string $dbConfig
 * @return boolean
 */
public function __construct($dbConfig=''){
if(!class_exists("PDO")){
self::throw_exception('不支持PDO，请先开启');
 }
if(!is_array($dbConfig)){
$dbConfig=array(
'hostname'=>DB_HOST,
'username'=>DB_USER,
'password'=>DB_PWD,
'database'=>DB_NAME,
'hostport'=>DB_PORT,
'dbms'=>DB_TYPE,
'dsn'=>DB_TYPE.":host=".DB_HOST.";dbname=".DB_NAME
 );
 }
if(empty($dbConfig['hostname']))self::throw_exception('没有定义数据库配置，请先定义');
self::$config=$dbConfig;
if(empty(self::$config['params']))self::$config['params']=array();
if(!isset(self::$link)){
$configs=self::$config;
if(self::$pconnect){
//开启长连接，添加到配置数组中
$configs['params'][constant("PDO::ATTR_PERSISTENT")]=true;
 }
try{
self::$link=new PDO($configs['dsn'],$configs['username'],$configs['password'],$configs['params']);
 }catch(PDOException $e){
self::throw_exception($e->getMessage());
 }
if(!self::$link){
self::throw_exception('PDO连接错误');
return false;
 }
self::$link->exec('SET NAMES '.DB_CHARSET);
self::$dbVersion=self::$link->getAttribute(constant("PDO::ATTR_SERVER_VERSION"));
self::$connected=true;
unset($configs);
 }
 }

/**
 * 得到所有记录
 * @param string $sql
 * @return unknown
 */
public static function getAll($sql=null){
if($sql!=null){
self::query($sql);
 }
$result=self::$PDOStatement->fetchAll(constant("PDO::FETCH_ASSOC"));
return $result;
 }
/**
 * 得到结果集中的一条记录
 * @param string $sql
 * @return mixed
 */
public static function getRow($sql=null){
if($sql!=null){
self::query($sql);
 }
$result=self::$PDOStatement->fetch(constant("PDO::FETCH_ASSOC"));
return $result;
 }
/**
 * 根据主键查找记录
 * @param string $tabName
 * @param int $priId
 * @param string $fields
 * @return mixed
 */
public static function findById($tabName,$priId,$fields='*'){
$sql='SELECT %s FROM %s WHERE id=%d';
return self::getRow(sprintf($sql,self::parseFields($fields),$tabName,$priId));
 }

/**
 * 执行普通查询
 * @param unknown $tables
 * @param string $where
 * @param string $fields
 * @param string $group
 * @param string $having
 * @param string $order
 * @param string $limit
 * @return Ambigous <unknown, unknown, multitype:>
 */
public static function find($tables,$where=null,$fields='*',$group=null,$having=null,$order=null,$limit=null){
$sql='SELECT '.self::parseFields($fields).' FROM '.$tables
 .self::parseWhere($where)
 .self::parseGroup($group)
 .self::parseHaving($having)
 .self::parseOrder($order)
 .self::parseLimit($limit);
$dataAll=self::getAll($sql);
return count($dataAll)==1?$dataAll[0]:$dataAll;
 }
/*
 array(
 'username'=>'imooc',
 'password'=>'imooc',
 'email'=>'[e-mail]',
 'token'=>'123abc',
 'token_exptime'=>'123123',
 'regtime'=>'123456'
 )
 INSERT user(username,password,email,token,token_exptime,regtime)
 VALUES('aa','aa','[e-mail]','bb','123123','123456')
 */
/**
 * 添加记录的操作
 * @param array $data
 * @param string $table
 * @return Ambigous <boolean, unknown, number>
 */
public static function add($data,$table){
$keys=array_keys($data);
 array_walk($keys,array('PdoMySQL','addSpecialChar'));
$fieldsStr=join(',',$keys);
$values="'".join("','",array_values($data))."'";
$sql="INSERT {$table}({$fieldsStr}) VALUES({$values})";
//echo $sql;
return self::execute($sql);
 }
/*
 array(
 'username'=>'imooc111',
 'password'=>'imooc222',
 'email'=>'[e-mail]',
 'token'=>'4444',
 'token_exptime'=>'1234444',
 'regtime'=>'12345678'
 )
 UPDATE user SET username='imooc111',password='imooc222'.... WHERE id<=38 ORDER BY username limit 0,1
 */
/**
 * 更新记录
 * @param array $data
 * @param string $table
 * @param string $where
 * @param string $order
 * @param string $limit
 * @return Ambigous <boolean, unknown, number>
 */
public static function update($data,$table,$where=null,$order=null,$limit=0){
//$sets = '';
foreach($data as $key=>$val){
$sets .= $key."='".$val."',";
 }
//echo $sets;
$sets=rtrim($sets,',');
$sql="UPDATE {$table} SET {$sets} ".self::parseWhere($where).self::parseOrder($order).self::parseLimit($limit);
return self::execute($sql);
 }
/**
 * 删除记录的操作
 * @param string $table
 * @param string $where
 * @param string $order
 * @param number $limit
 * @return Ambigous <boolean, unknown, number>
 */
public static function delete($table,$where=null,$order=null,$limit=0){
$sql="DELETE FROM {$table} ".self::parseWhere($where).self::parseOrder($order).self::parseLimit($limit);
return self::execute($sql);
 }
/**
 * 得到最后执行的SQL语句
 * @return boolean|Ambigous <string, string>
 */
public static function getLastSql(){
$link=self::$link;
if(!$link)return false;
return self::$queryStr;
 }
/**
 * 得到上一步插入操作产生AUTO_INCREMENT
 * @return boolean|string
 */
public static function getLastInsertId(){
$link=self::$link;
if(!$link)return false;
return self::$lastInsertId;
 }
/**
 * 得到数据库的版本
 * @return boolean|mixed
 */
public static function getDbVerion(){
$link=self::$link;
if(!$link)return false;
return self::$dbVersion;
 }
/**
 * 得到数据库中数据表
 * @return multitype:mixed
 */
public static function showTables(){
$tables=array();
if(self::query("SHOW TABLES")){
$result=self::getAll();
foreach($result as $key=>$val){
$tables[$key]=current($val);
 }
 }
return $tables;
 }
/**
 * 解析Where条件
 * @param unknown $where
 * @return string
 */
public static function parseWhere($where){
$whereStr='';
if(is_string($where)&&!empty($where)){
$whereStr=$where;
 }
return empty($whereStr)?'':' WHERE '.$whereStr;
 }
/**
 * 解析group by
 * @param unknown $group
 * @return string
 */
public static function parseGroup($group){
$groupStr='';
if(is_array($group)){
$groupStr.=' GROUP BY '.implode(',',$group);
 }elseif(is_string($group)&&!empty($group)){
$groupStr.=' GROUP BY '.$group;
 }
return empty($groupStr)?'':$groupStr;
 }
/**
 * 对分组结果通过Having子句进行二次删选
 * @param unknown $having
 * @return string
 */
public static function parseHaving($having){
$havingStr='';
if(is_string($having)&&!empty($having)){
$havingStr.=' HAVING '.$having;
 }
return $havingStr;
 }
/**
 * 解析Order by
 * @param unknown $order
 * @return string
 */
public static function parseOrder($order){
$orderStr='';
if(is_array($order)){
$orderStr.=' ORDER BY '.join(',',$order);
 }elseif(is_string($order)&&!empty($order)){
$orderStr.=' ORDER BY '.$order;
 }
return $orderStr;
 }
/**
 * 解析限制显示条数limit
 * limit 3
 * limit 0,3
 * @param unknown $limit
 * @return unknown
 */
public static function parseLimit($limit){
$limitStr='';
if(is_array($limit)){
if(count($limit)>1){
$limitStr.=' LIMIT '.$limit[0].','.$limit[1];
 }else{
$limitStr.=' LIMIT '.$limit[0];
 }
 }elseif(is_string($limit)&&!empty($limit)){
$limitStr.=' LIMIT '.$limit;
 }
return $limitStr;
 }
/**
 * 解析字段
 * @param unknown $fields
 * @return string
 */
public static function parseFields($fields){
if(is_array($fields)){
 array_walk($fields,array('PdoMySQL','addSpecialChar'));
$fieldsStr=implode(',',$fields);
 }elseif(is_string($fields)&&!empty($fields)){
if(strpos($fields,'`')===false){
$fields=explode(',',$fields);
 array_walk($fields,array('PdoMySQL','addSpecialChar'));
$fieldsStr=implode(',',$fields);
 }else{
$fieldsStr=$fields;
 }
 }else{
$fieldsStr='*';
 }
return $fieldsStr;
 }
/**
 * 通过反引号引用字段，
 * @param unknown $value
 * @return string
 */
public static function addSpecialChar(&$value){
if($value==='*'||strpos($value,'.')!==false||strpos($value,'`')!==false){
//不用做处理
 }elseif(strpos($value,'`')===false){
$value='`'.trim($value).'`';
 }
return $value;
 }
/**
 * 执行增删改操作，返回受影响的记录的条数
 * @param string $sql
 * @return boolean|unknown
 */
public static function execute($sql=null){
$link=self::$link;
if(!$link) return false;
self::$queryStr=$sql;
if(!empty(self::$PDOStatement))self::free();
$result=$link->exec(self::$queryStr);
self::haveErrorThrowException();
if($result){
self::$lastInsertId=$link->lastInsertId();
self::$numRows=$result;
return self::$numRows;
 }else{
return false;
 }
 }
/**
 释放结果集
 */
public static function free(){
self::$PDOStatement=null;
 }
public static function query($sql=''){
$link=self::$link;
if(!$link) return false;
//判断之前是否有结果集，如果有的话，释放结果集
if(!empty(self::$PDOStatement))self::free();
self::$queryStr=$sql;
self::$PDOStatement=$link->prepare(self::$queryStr);
$res=self::$PDOStatement->execute();
self::haveErrorThrowException();
return $res;
 }
public static function haveErrorThrowException(){
$obj=empty(self::$PDOStatement)?self::$link: self::$PDOStatement;
$arrError=$obj->errorInfo();
//print_r($arrError);
if($arrError[0]!='00000'){
self::$error='SQLSTATE: '.$arrError[0].' <br/>SQL Error: '.$arrError[2].'<br/>Error SQL:'.self::$queryStr;
self::throw_exception(self::$error);
return false;
 }
if(self::$queryStr==''){
self::throw_exception('没有执行SQL语句');
return false;
 }
 }
/**
 * 自定义错误处理
 * @param unknown $errMsg
 */
public static function throw_exception($errMsg){
echo '<div style="width:80%;background-color:#ABCDEF;color:black;font-size:20px;padding:20px 0px;">
 '.$errMsg.'
 </div>';
 }
/**
 * 销毁连接对象，关闭数据库
 */
public static function close(){
self::$link=null;
 }

}
// require_once 'config.php';
// $PdoMySQL=new PdoMySQL;
//var_dump($PdoMySQL);
// $sql='SELECT * FROM user1';
// print_r($PdoMySQL->getAll($sql));
// $sql='SELECT * FROM user WHERE id=36';
// print_r($PdoMySQL->getRow($sql));
// $sql='INSERT user(username,password,email,token,token_exptime,regtime)';
// $sql.=" VALUES('imooc1113','imooc1113','[e-mail]','abcdefgh','1392348346','12313346')";
// //echo $sql;
// var_dump($PdoMySQL->execute($sql));
// echo '<hr/>';
// echo $PdoMySQL::$lastInsertId;
// $sql='DELETE FROM user WHERE id>=37';
// var_dump($PdoMySQL->execute($sql));
// $sql='UPDATE user SET username="king1234" WHERE id=36';
// var_dump($PdoMySQL->execute($sql));
// $tabName='user';
// $priId='36';
// //$fields='username,email';
// $fields=array('username','email','regtime');
// $fields='*';
// print_r($PdoMySQL->findById($tabName,$priId,$fields));
//print_r($PdoMySQL->findById($tabName, $priId));
//$tables='user';
//print_r($PdoMySQL->find($tables));
//print_r($PdoMySQL->find($tables,'id>=30'));
// print_r($PdoMySQL->find($tables,'id>=30','username,email'));
//print_r($PdoMySQL->find($tables,'id<=10','*','status'));
//print_r($PdoMySQL->find($tables,'id<=10','*','status','count(*)>=6'));
//print_r($PdoMySQL->find($tables,'id>5','*',null,null,'username desc,id desc'));
//print_r($PdoMySQL->find($tables,null,'*',null,null,null,array(3,5)));
// $data= array(
// 'username'=>'imooc',
// 'password'=>'imooc',
// 'email'=>'[e-mail]',
// 'token'=>'123abc',
// 'token_exptime'=>'123123',
// 'regtime'=>'123456'
// );
// var_dump($PdoMySQL->add($data,$tables));
// $data=array(
// 'username'=>'imooc111',
// 'password'=>'imooc222',
// 'email'=>'[e-mail]',
// 'token'=>'4444',
// 'token_exptime'=>'1234444',
// 'regtime'=>'12345678'
// );
//var_dump($PdoMySQL->update($data,$tables,'id<=38',' id DESC','2'));

//var_dump($PdoMySQL->delete($tables,'id>35'));
//var_dump($PdoMySQL->delete($tables,'id>3','id DESC','5'));
//print_r($PdoMySQL->showTables());