php封装的pdo数据库操作工具类与用法示例

<?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;//判断是否连接成功
public static $PDOStatement = null;//保证PDOStatement对象
public static $queryStr = null;//保存最后执行的操作
public static $error = null;//保存错误信息
public static $lastInsertId = null;//保存上一步插入操作保存的AUTO_INCREMANT
public static $numRows = null;//受影响记录的条数
/**
* 构造函数，连接数据库
*
* @param   array|string $dbConfig The database configuration
*
* @return   boolean    ( description_of_the_return_value )
*/
public function __construct($dbConfig=''){
if(!class_exists("PDO")){
self::throw_exception("不支持PDO,请先开启");
}
if(!is_array($dbConfig)){
$dbConfig = array(
'hostname' =  'localhost',
'username' =  'root',
'password' =  '1234',
'database' =  'test',
'hostport' =  '3306',
'dbms'   =  'mysql',
'dsn'   =  'mysql:host=localhost;dbname=test'
);
}
if(empty($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 utf8");
self::$dbVersion = self::$link- getAttribute(constant("PDO::ATTR_SERVER_VERSION"));
unset($configs);
}
}
/**
* 得到所有记录
*
* @param   <type  $sql  The sql
*
* @return   <type  All.
*/
public static function getAll($sql=null){
if($sql!=null){
self::query($sql);
}
$result = self::$PDOStatement- fetchAll(constant("PDO::FETCH_ASSOC"));
return $result;
}
/**
* 得到一条记录
*
* @param   <type  $sql  The sql
*
* @return   <type  The row.
*/
public static function getRow($sql=null){
if($sql!=null){
self::query($sql);
}
$result = self::$PDOStatement- fetch(constant("PDO::FETCH_ASSOC"));
return $result;
}
/**
* 执行增删改操作，返回受影响记录的条数
*
* @param   <type   $sql  The sql
*
* @return   boolean ( description_of_the_return_value )
*/
public static function execute($sql=null){
$link = self::$link;
if(!$link)return false;
if($sql!=null){
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 $result;
}else{
return false;
}
}
/**
* 根据主键查找记录
*
* @param   <type  $tabName The tab name
* @param   <type  $priId  The pri identifier
* @param   string $fields  The fields
*
* @return   <type  ( description_of_the_return_value )
*/
public static function findById($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   <type  $tables The tables
* @param   <type  $where  The where
* @param   string $fields The fields
* @param   <type  $group  The group
* @param   <type  $having The having
* @param   <type  $order  The order
* @param   <type  $limit  The limit
*
* @return   <type  ( description_of_the_return_value )
*/
public static function find($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);
$data = self::getAll($sql);
return $data;
}
/**
* 添加记录
*
* @param   <type  $data  The data
* @param   <type  $table The table
*
* @return   <type  ( description_of_the_return_value )
*/
public static function add($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})";
return self::execute($sql);
}
/**
* 更新数据
*
* @param   <type  $data  The data
* @param   <type  $table The table
* @param   <type  $where The where
* @param   <type  $order The order
* @param   <type  $limit The limit
*/
public static function update($data,$table,$where=null,$order=null,$limit=null){
$sets = '';
foreach ($data as $key =  $value) {
$sets .= $key."='".$value."',";
}
$sets = rtrim($sets,',');
$sql = "UPDATE {$table} SET {$sets}".self::parseWhere($where).self::parseOrder($order).self::parseLimit($limit);
echo $sql;
}
/**
* 删除数据
*
* @param   <type  $data  The data
* @param   <type  $table The table
* @param   <type  $where The where
* @param   <type  $order The order
* @param   <type  $limit The limit
*
* @return   <type  ( description_of_the_return_value )
*/
public static function delete($table,$where=null,$order=null,$limit=null){
$sql = "DELETE FROM {$table} ".self::parseWhere($where).self::parseOrder($order).self::parseLimit($limit);
return self::execute($sql);
}
/**
* 执行查询
*
* @param   string  $sql  The sql
*
* @return   boolean ( description_of_the_return_value )
*/
public static function query($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;
}
/**
* 获取最后执行的sql
*
* @return   boolean The last sql.
*/
public static function getLastSql(){
$link = self::$link;
if(!$link){
return false;
}
return self::$queryStr;
}
/**
* 获取最后插入的ID
*
* @return   boolean The last insert identifier.
*/
public static function getLastInsertId(){
$link = self::$link;
if(!$link){
return false;
}
return self::$lastInsertId;
}
/**
* 获得数据库的版本
*
* @return   boolean The database version.
*/
public static function getDbVersion(){
$link = self::$link;
if(!$link){
return false;
}
return self::$dbVersion;
}
/**
* 得到数据库中表
*
* @return   array ( description_of_the_return_value )
*/
public static function showTables(){
$tables = array();
if(self::query("show tables")){
$result = self::getAll();
foreach ($result as $key =  $value) {
$tables[$key] = current($value);
}
}
return $tables;
}
/**
* 解析where条件
*
* @param   <type  $where The where
*
* @return   <type  ( description_of_the_return_value )
*/
public static function parseWhere($where){
$whereStr = '';
if(is_string($where)&&!empty($where)){
$whereStr = $where;
}
return empty($whereStr) ? '' : ' WHERE '.$whereStr;
}
/**
* 解析group
*
* @param   <type  $group The group
*
* @return   <type  ( description_of_the_return_value )
*/
public static function parseGroup($group){
$groupStr = '';
if(is_array($group)){
$groupStr = implode(',', $group);
}elseif(is_string($group)&&!empty($group)){
$groupStr = $group;
}
return empty($groupStr) ? '' : ' GROUP BY '.$groupStr;
}
/**
* 解析having
*
* @param   <type  $having The having
*
* @return   <type  ( description_of_the_return_value )
*/
public static function parseHaving($having){
$havingStr = '';
if(is_string($having)&&!empty($having)){
$havingStr = $having;
}
return empty($havingStr) ? '' : ' HAVING '.$havingStr;
}
/**
* 解析order
*
* @param   <type  $order The order
*
* @return   <type  ( description_of_the_return_value )
*/
public static function parseOrder($order){
$orderStr = '';
if(is_string($order)&&!empty($order)){
$orderStr = $order;
}
return empty($orderStr) ? '' : ' ORDER BY '.$orderStr;
}
/**
* 解析limit
*
* @param   <type  $limit The limit
*
* @return   <type  ( description_of_the_return_value )
*/
public static function parseLimit($limit){
$limitStr = '';
if(is_array($limit)){
$limitStr = implode(',', $limit);
}elseif(is_string($limit)&&!empty($limit)){
$limitStr = $limit;
}
return empty($limitStr) ? '' : ' LIMIT '.$limitStr;
}
/**
* 解析字段
*
* @param   <type  $fields The fields
*
* @return   string ( description_of_the_return_value )
*/
public static function parseFields($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; 
}
/**
* 通过反引号引用字字段
*
* @param   string $value The value
*
* @return   string ( description_of_the_return_value )
*/
public static function addSpecialChar(&$value){
if($value==="*"||strpos($value,'.')!==false||strpos($value,'`')!==false){
//不用做处理
}elseif(strpos($value, '`')===false){
$value = '`'.trim($value).'`';
}
return $value;
}
/**
* 释放结果集
*/
public static function free(){
self::$PDOStatement = null;
}
/**
* 抛出错误信息
*
* @return   boolean ( description_of_the_return_value )
*/
public static function haveErrorThrowException(){
$obj = empty(self::$PDOStatement) ? self::$link : self::$PDOStatement;
$arrError = $obj- errorInfo();
if($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   <type  $errMsg The error message
*/
public static function throw_exception($errMsg){
echo $errMsg;
}
/**
* 销毁连接对象，关闭数据库
*/
public static function close(){
self::$link = null;
}
}
$pdo = new PdoMysql();
var_dump($pdo- showTables());