MySQL数据库操作类(PHP实现，支持连贯操作)

 <?php
 /**
  * Author: suvan
  * CreateTime: 2018/2/27
  * 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,$user,$passowrd,$database,$port=){
         $this->_initialize();
         if(!isset($host)||!isset($user)||!isset($passowrd)||!isset($database)){
             return false;
         }else{
             $this->_host     = $host;
             $this->_user     = $user;
             $this->_password = $passowrd;
             $this->_database = $database;
             $this->_port     = $port;
             $_dbObj = new mysqli($host,$user,$passowrd,$database,$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]);
     }
     /**
      * 利用__call方法实现一些特殊的方法(对于调用类中不存在方法的解决方案)
      * @access public
      * @param string $method 方法名称
      * @param array $args 调用参数
      * @return mixed
      */
     public function __call($method,$args) {
         /*if(in_array(strtolower($method),$this->methods,true)) {
             // 连贯操作的实现
             $this->options[strtolower($method)] =   $args[0];
             return $this;
         }elseif(in_array(strtolower($method),array('count','sum','min','max','avg'),true)){
             // 统计查询的实现
             $field =  isset($args[0])?$args[0]:'*';
             return ;
         }elseif(strtolower(substr($method,0,5))=='getby') {
             // 根据某个字段获取记录
             $field   =   parse_name(substr($method,5));
             $where[$field] =  $args[0];
             return ;
         }elseif(strtolower(substr($method,0,10))=='getfieldby') {
             // 根据某个字段获取记录的某个值
             $name   =   parse_name(substr($method,10));
             $where[$name] =$args[0];
             return ;
         }elseif(isset($this->_scope[$method])){// 命名范围的单独调用支持
             return ;
         }else{

         }*/
     }
     /*
      * 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($i=;$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;
         $search_res = mysqli_query($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 $field 指定字段（字符串传入使用，间隔）
      * @return array 数据表中指定字段信息
      * */
     public function getField($field){
         $fields = self::param_handle($field);
         $count = count($fields);
         for($i=;$i<$count;$i++){
             $index = $fields[$i];
             $sql = 'select '.$index.' from '.$this->_table;
             $res = mysqli_query($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=;$i<$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 data(array $data){
         $values = array();
         $fields = array();
         if(is_array($data)){
             foreach($data as $key=>$value){
                 if(is_array($value)){       //二维数组
                     $tip = ;
                     array_push($values,'('.implode(',',array_values($value)).')');
                     array_push($fields,'('.implode(',',array_keys($value)).')');
                 }else{      //一维数组
                     $tip = ;
                 }
             }
         }else{
             return false;
         }
         if(!$tip){
             array_push($values,'('.implode(',',array_values($data)).')');
             array_push($fields,'('.implode(',',array_keys($data)).')');
         }
         $this->data['fields'] = $fields[];
         $this->data['values'] = implode(',',$values);
         return $this;
     }
     /*
      * 数据新增函数
      * @access public
      * @return mixed 数据库新增信息
      * */
     public function add(){
         $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);
     }
 }

　　使用示例

 include '/classes/db.php';
             $db = new \Database('localhost', 'root', '', 'weixin');
             //$db = new \mysqli('localhost','root','901230','weixin');
             //$db->select_db('visitor');
             //dump($db->error());
             //$db->change_user('helen','901230');
             $table = 'zyd_fuweng_user';
             //dump($db->select_table_fields($table));
             //dump($db->error());
             $db->select_table($table);
             $param1 = '';
             $param2 = 'id>1,record>100';
             $param3 = array(
                 /*array('count'=>1,'openid'=>'123','record'=>'100'),
                 array('count'=>2,'openid'=>'234','record'=>'200'),*/
                 array('count' => , 'openid' => '', 'record' => '')
             );
             $param4 = array('count' => , 'openid' => '', 'record' => '');
             //dump($db->where('id=4')->save($param4));
             dump($db->where('count=4')->delete());

             die;
             dump($db->data($param3)->add());
             dump(array_keys($param3));
             dump(array_values($param3));
             dump(implode(',', array_values($param3)));
             dump(implode(',', array_keys($param3)));

             dump($db->where($param2)->order('id')->limit()->find());
             dump($db->options_handle($param1));
             dump($db->options_handle($param2));
             dump($db->options_handle($param3));
             $array = array('id', 'count');

             $num = '';
             if (is_string($num)) {
                 echo 'true';
             }

             dump($db->getField($array));
             dump($db->select_table_fields($table));
             /*$array = array('a','b');
             $array1 = array();
             dump($db->getField('a,b'));
             dump($db->getField($array));
             dump($db->getField($array1));
             dump($db->getField(''));*/
             /*$str = '';
             if(empty($str)){
                 echo 'true';
             }*/
             /*$model = M('zyd_fuweng_user');
             $res = $model->getField('create_time,count');
             dump($res);*/
             die;
             //
             $table = 'zyd_fuweng_user';
             //选择指定的数据库，并返回其中全部信息
             $table_msg = $db->select_table($table);
             //选择指定数据库，返回数据库的字段信息
             $table_field_msg = $db->select_table_fields($table);
             //条件搜索，传入条件均为数据
             $where = array(
                 'id' =>
             );
             $data = array(
                 'headimgurl' => 'helen.jpg'
             );
             dump($db->where($where)->field('field'));
             dump($table);

             /*$dbObj = new \mysqli('localhost','helen','901230','weixin','3306');
             //$query = 'select * from zyd_fuweng_user';
             $query = 'show fields from zyd_fuweng_user';
             $tables = mysqli_query($dbObj,$query);
             //dump($tables);
             $count = $tables->num_rows;
             $arr = array();
             for($i=0;$i<$count;$i++){
                 $row = $tables->fetch_assoc();
                 //dump($row);
                 array_push($arr,$row);
             }
             mysqli_free_result($tables);
             dump($arr);
             die;
             $query1 = 'select * from zyd_fuweng_user';
             $table_msg = mysqli_query($dbObj,$query1);
             //输出查询结果
             $num = $table_msg->num_rows;
             for($i=0;$i<$num;$i++){
                 $row = $table_msg->fetch_assoc();
                 dump($row);
             }
             dump($dbObj);
             dump($tables);
             dump($table_msg);
             $res = mysqli_close($dbObj);
             dump($res);*/