PHP实现MySQL类
<?php
/**
* Author: helen
* CreateTime: 2016/4/12 20:14
* description: 数据库操作类(仅对接MySQL数据库,主要利用MySQLi函数)
*/
class Database{
//MySQL主机地址
private $_host;
//MySQL用户名
private $_user;
//MySQL用户密码
private $_password;
//指定数据库名称
private $_database;
//MySQL数据库端口号
private $_port;
private $_socket;
//当前数据库对象
private $_dbObj;
//数据库表
private $_table;
//数据库表对象
private $_tableObj;
// 最近错误信息
protected $error = '';
// 数据信息
protected $data = array();
// 查询表达式参数
protected $options = array();
protected $_validate = array(); // 自动验证定义
protected $_auto = array(); // 自动完成定义
protected $_map = array(); // 字段映射定义
protected $_scope = array(); // 命名范围定义
// 链操作方法列表
protected $methods = array('strict','order','alias','having','group','lock','distinct','auto','filter','validate','result','token','index','force');
/**
* Database类初始化函数
* 取得DB类的实例对象 字段检查
* @access public
* @param string $host MySQL数据库主机名
* @param string $user MySQL数据库用户名
* @param string $password MySQL数据库密码
* @param string $database 指定操作的数据库
* @return mixed 数据库连接信息、错误信息
*/
public function __construct($host,$user,$password,$database,$port=3306){
$this->_initialize();
if(!isset($host)||!isset($user)||!isset($password)||!isset($database)){
return false;
}else{
$this->_host = $host;
$this->_user = $user;
$this->_password = $password;
$this->_database = $database;
$this->_port = $port;
$_dbObj = new mysqli($host,$user,$password,$database,$port);
if($_dbObj->connect_errno){
$this->error = $_dbObj->connect_error;
return false;
}else{
$this->_dbObj = $_dbObj;
return $this;
}
}
}
/**
* 错误信息函数
* 返回数据库操作过程中最后一次执行时的错误信息
* @access public
* @return mixed 数据库连接错误信息(正常返回'')
*/
public function error(){
return $this->error;
}
// 回调方法 初始化模型
protected function _initialize() {}
/**
* 设置数据对象的值
* @access public
* @param string $name 名称
* @param mixed $value 值
* @return void
*/
public function __set($name,$value) {
// 设置数据对象属性
$this->data[$name] = $value;
}
/**
* 获取数据对象的值
* @access public
* @param string $name 名称
* @return mixed
*/
public function __get($name) {
return isset($this->data[$name])?$this->data[$name]:null;
}
/**
* 检测数据对象的值
* @access public
* @param string $name 名称
* @return boolean
*/
public function __isset($name) {
return isset($this->data[$name]);
}
/**
* 销毁数据对象的值
* @access public
* @param string $name 名称
* @return void
*/
public function __unset($name) {
unset($this->data[$name]);
}
/*
* 选择数据库
* @access public
* @param string $database 选择的数据库名称
* @return mixed 数据库连接信息
* */
public function select_db($database){
$select_db = mysqli_select_db($this->_dbObj,$database);
if($select_db){
$this->_database = $database;
$_dbObj = new mysqli($this->_host,$this->_user,$this->_password,$database,$this->_port);
$this->_dbObj = $_dbObj;
return $this;
}else{
$this->error = mysqli_error($this->_dbObj);
return false;
}
}
/*
* 数据库用户更换
* @access public
* @param string $user 数据库用户名称
* @param string $password 数据库用户密码
* @return mixed 数据库连接信息
* */
public function change_user($user,$password){
$change_user = mysqli_change_user($this->_dbObj,$user,$password,$this->_database);
if($change_user){
$this->_user = $user;
$this->_password = $password;
$_dbObj = new mysqli($this->_host,$this->_user,$this->_password,$this->_database,$this->_port);
$this->_dbObj = $_dbObj;
return $this;
}else{
$this->error = mysqli_error($this->_dbObj);
return false;
}
}
/*
* 查询数据库中所有的表名
* @access public
* @return array 数据表的数量和表名
* */
public function tables(){
$sql = 'show tables';
$search_res = mysqli_query($this->_dbObj,$sql);
if($search_res){
$num_rows = $search_res->num_rows;
$tables_msg = array(
'count'=>$num_rows,
'tables'=>array()
);
for($i=0;$i<$num_rows;$i++){
$row = $search_res->fetch_assoc();
$key = 'Tables_in_'.$this->_database;
array_push($tables_msg['tables'],$row[$key]);
}
mysqli_free_result($search_res);
return $tables_msg;
}else{
mysqli_free_result($search_res);
return false;
}
}
/*
* 获取指定表中所有信息
* @access public
* @param string $table 数据表名称
* @return array 数据表的详细信息
* */
public function select_table($table){
$sql = 'select * from '.$table;
// var_dump($this->_dbObj);
$search_res = mysqli_query($this->_dbObj,$sql);
if($search_res){
$this->_table = $table;
$table_msg = self::query_handle($search_res);
$this->_tableObj = $table_msg;
mysqli_free_result($search_res);
return $table_msg;
}else{
mysqli_free_result($search_res);
return false;
}
}
/*
* 获取指定表的字段详细信息
* @access public
* @param string $table 数据表名称
* @return array 数据表的字段详细信息
* */
public function select_table_fields($table){
$sql = 'show fields from '.$table;
$search_res = mysqli_query($this->_dbObj,$sql);
if($search_res){
$this->_table = $table;
$fields_msg = self::query_handle($search_res);
mysqli_free_result($search_res);
return $fields_msg;
}else{
mysqli_free_result($search_res);
return false;
}
}
/*
* 获取数据表中指定字段信息(允许多字段同时查询)
* @access public
* @param mixed $field 指定字段(字符串传入使用,间隔)
* @return array 数据表中指定字段信息
* */
public function get_field($field){
$option = self::option();
$fields = self::param_handle($field);
$count = count($fields);
for($i=0;$i<$count;$i++){
$index = $fields[$i];
// $sql = 'select '.$index.' from '.$this->_table.' where '.$this->options['where'];
$sql = 'select '.$index.' from '.$this->_table.' '.$option;
$res = mysqli_query($this->_dbObj,$sql);
$field_msg[$index] = self::query_handle($res);
}
return $field_msg;
}
/*
* mysqli_query函数结果处理函数
* @access protected
* @param object $obj mysqli_query函数结果
* @return array 数据表中指定字段信息
* */
protected function query_handle($obj){
$res = array();
for($i=0;$i<$obj->num_rows;$i++){
$row = $obj->fetch_assoc();
array_push($res,$row);
}
return $res;
}
/*
* 传入参数处理函数
* @access protected
* @param mixed $param 传入参数
* @return array 处理后数组数据
* */
public function param_handle($param){
if(is_string($param)&&!empty($param)){
$params = explode(',',$param);
}elseif(is_array($param)&&!empty($param)){
$params = $param;
}else{
return false;
}
return $params;
}
/*
* 查询表达式参数处理函数
* @access protected
* @param mixed $param 传入参数(where limit order)
* @return string 处理后字符串数据
* */
public function options_handle($param){
if(is_numeric($param)){
$option = $param;
}elseif(is_string($param)&&!empty($param)&&!is_numeric($param)){
$params = explode(',',$param);
$count = count($params);
$option = implode(' and ',$params);
}elseif(is_array($param)&&!empty($param)){
$params = $param;
$count = count($params);
$arr = array();
foreach($param as $key=>$value){
$tip = "$key=$value ";
array_push($arr,$tip);
}
$option = implode(' and ',$arr);
}else{
return false;
}
return $option;
}
/*
* 查询表达式$options处理函数
* @access protected
* @return string 处理后字符串数据
* */
protected function option(){
$options = $this->options;
$option = '';
if(isset($options['where'])){
$option .= 'where '.$options['where'].' ';
}
if(isset($options['order'])){
$option .= 'order by '.$options['order'].' '.$options['order_type'].' ';
}
if(isset($options['limit'])){
$option .= 'limit '.$options['limit'];
}
return $option;
}
/*
* 根据查询表达式查询数据(符合条件的所有记录)
* @access public
* @return array 满足查询表达式的特定数据
* */
public function find(){
$option = self::option();
$sql = 'select * from '.$this->_table.' '.$option;
$search_res = mysqli_query($this->_dbObj,$sql);
$msg = self::query_handle($search_res);
return $msg;
}
/*
* 查询表达式 where处理函数
* @access public
* @param mixed $where where查询条件
* @return object $this
* */
public function where($where){
$this->options['where'] = self::options_handle($where);
return $this;
}
/*
* 查询表达式 limit处理函数
* @access public
* @param mixed $limit limit查询条件(数字)
* @return object $this
* */
public function limit($limit){
$this->options['limit'] = self::options_handle($limit);
return $this;
}
/*
* 查询表达式 order处理函数
* @access public
* @param string $order order查询条件
* @param string $type order查询条件的顺序(默认降序)
* @return object $this
* */
public function order($order,$type='desc'){
$this->options['order'] = $order;
$this->options['order_type'] = $type;
return $this;
}
/*
* 数据处理函数(最多处理二维数据)
* @access public
* @param array $data 需要插入的数据
* @return object $this
* */
public function ready_data(array $data){
$values = array();
$fields = array();
if(is_array($data)){
foreach($data as $key=>$value){
if(is_array($value)){ //二维数组
$tip = 1;
array_push($values,"('".implode("','",array_values($value))."')");
array_push($fields,'('.implode(',',array_keys($value)).')');
}else{ //一维数组
$tip = 0;
}
}
}else{
return false;
}
if(!$tip){
array_push($values,"('".implode("','",array_values($value))."')");
array_push($fields,'('.implode(',',array_keys($data)).')');
}
$this->data['fields'] = $fields[0];
$this->data['values'] = implode(',',$values);
return $this;
}
/*
* 数据新增函数
* @access public
* @return mixed 数据库新增信息
* */
public function add_data(){
$fields = $this->data['fields'];
$values = $this->data['values'];
$sql = 'INSERT INTO '.$this->_table.$fields.'VALUES'.$values;
$res = mysqli_query($this->_dbObj,$sql);
return $res;
}
/*
* 数据更新函数(一维数组)
* @access public
* @param array $data 需要更新的数据
* @return mixed 数据库新增信息
* */
function save(array $data){
$tip = array();
if(is_array($data)){
foreach($data as $key=>$value){
array_push($tip,"$key=$value");
}
}else{
return false;
}
$set_msg = implode(',',$tip);
$sql = 'UPDATE '.$this->_table.' SET '.$set_msg.' WHERE '.$this->options['where'];
$res = mysqli_query($this->_dbObj,$sql);
return $res;
}
/*
* 数据删除函数
* @access public
* @return mixed 数据库删除信息
* */
public function delete(){
$sql = 'DELETE FROM '.$this->_table.' WHERE '.$this->options['where'];
$res = mysqli_query($this->_dbObj,$sql);
return $res;
}
/*
* SQL语句查询
* */
public function query($sql){
$search_res = mysqli_query($this->_dbObj,$sql);
return $search_res;
}
/*
* mysql中查询语句
* */
protected function sql(){
/*
* 基本SQL语句
* 插入数据:INSERT INTO tb_name(id,name,score)VALUES(NULL,'张三',140),(NULL,'张四',178),(NULL,'张五',134);
* 更新语句:UPDATE tb_name SET score=189 WHERE id=2;
* 删除数据:DELETE FROM tb_name WHERE id=3;
* WHERE语句:SELECT * FROM tb_name WHERE id=3;
* HAVING 语句:SELECT * FROM tb_name GROUP BY score HAVING count(*)>2
* 相关条件控制符:=、>、<、<>、IN(1,2,3......)、BETWEEN a AND b、NOT AND 、OR Linke()用法中 % 为匹配任意、 _ 匹配一个字符(可以是汉字)IS NULL 空值检测
* MySQL的正则表达式:SELECT * FROM tb_name WHERE name REGEXP '^[A-D]' //找出以A-D 为开头的name
* */
}
/*
* 关闭连接
* */
public function close(){
$close = mysqli_close($this->_dbObj);
if($close){
return true;
}else{
return false;
}
}
function __destruct(){
// mysqli_close($this->_dbObj);
}
}