本文共 7818 字，大约阅读时间需要 26 分钟。

这个代码有点多，比较复杂；

先在工程项目里，添加一个文件夹（library_1），然后将下面的代码都建立在这个文件夹中统一管理。

首页 index.php

   field('emp_name,emp_dept')->select();echo "
";var_dump($data);echo "
";//调用model方法$emp_1 = model('emp_info');//准备插入数据的数组$emp_data = array(    'emp_name'=>'x',    'emp_dept'=>'d',    'date_birth'=>'2020-09-01',    'date_entry'=>'2020-09-02');//插入数据if($emp_id = $emp_1->add($emp_data)){    $emp_res = $emp_1->getById($emp_id);    echo "
";    var_dump($emp_res);    echo "
";}

自动加载类页面 init.php

   'localhost',    'user'=>'root',    'pwd'=>'mysql123',    'dbname'=>'test');//自动加载函数function my_autoload($className){    require_once "./{$className}.class.php";}//注册自动加载函数spl_autoload_register("my_autoload");//模型调用方法function model($tableName){    $model = $tableName.'Model';    return new $model($tableName);}

emp_infoModel.class.php

   tableName where emp_id=$id";        if($data = $this->db->fetchRow($sql))        {            return $data;        }        return false;    }}

模型基类 model.class.php

   tableName = $tableName;        //调用数据操作类的静态方法，获取数据库连接id        $this->db = mysqldb::getInstance($GLOBALS['db_config1']);    }    //字段    public function field($fields)    {        $this->fields = $fields;        return $this;    }    //整理字段    private function parseFields()    {        if(is_string($this->fields))        {            $this->fields = explode(',',$this->fields);        }        foreach ($this->fields as $k=>$v)        {            $this->fields[$k]="$v";        }        return implode(',',$this->fields);    }    //查询    public function select()    {        if(empty($this->fields))        {            $sql = "select * from $this->tableName";        }        else        {            $fields = $this->parseFields();            $sql = "select $fields from $this->tableName";            $this->fields = null;        }        return $this->db->fetchAll($sql);    }    //设置属性器    public function __set($name, $value)    {        $this->data[$name] = $value;    }    //获取属性器    public function __get($name)    {        return isset($this->data[$name])?$this->data[$name]:null;    }    //整理插入数据    private function parseData()    {        $field = array();        $value = array();        foreach ($this->data as $k=>$v)        {            $field[] = "$k";            $value[] = "'".$this->db->escapeString($v)."'";        }        return array(            'field'=>implode(',',$field),            'value'=>implode(',',$value),        );    }    //保存函数    public function add($data = array())    {        $this->data = array_merge($this->data,$data);        $data = $this->parseData();        $this->data = array();        $sql = "insert into $this->tableName({$data['field']}) values ({$data['value']})";        if($this->db->query($sql))        {            //        }        return false;    }}

数据库操作类 mysqldb.class.php

   'localhost',        'port'=>'3306',        'user'=>'root',        'pwd'=>'mysql123',        'charset'=>'utf8',        'dbname'=>'test',    );    //私有，数据库连接id    private $link;    //私有，数据库静态实例    private static $instance;    /**     * @param $params     */    //合并配置    private function initAttr($params)    {        $this->db_config = array_merge($this->db_config,$params);    }    /**     *     */    //连接函数    private function connectServer()    {        $host = $this->db_config['host'];        $port = $this->db_config['port'];        $user = $this->db_config['user'];        $pwd = $this->db_config['pwd'];        $dbname = $this->db_config['dbname'];        if ($link = mysqli_connect("$host:$port","$user","$pwd","$dbname"))        {            $this->link = $link;        }        else        {            die('数据库连接失败'.mysqli_error($this->link));        }    }    /**     *     */    //设置字符集    private function setCharset()    {        $sql = "set names {$this->db_config['charset']}";        $this->query($sql);        //mysqli_query($this->link,$sql);    }    /**     * @return bool     */    //选择默认库    private function selectDefaultDb()    {        if($this->db_config['dbname'] == '')        {            return false;        }        $sql = "use {$this->db_config['dbname']}";        $this->query($sql);        //mysqli_query($this->link,$sql);    }    /**     * mysqldb constructor.     * @param array $params     *     */    //构造函数    private function __construct($params = array())    {        $this->initAttr($params);        $this->connectServer();        $this->setCharset();        $this->selectDefaultDb();    }    /**     * @param $sql     * @return bool|mysqli_result     */    //查询    public function query($sql)    {        if($result = mysqli_query($this->link,$sql))        {            return $result;        }        else        {            echo 'SQL执行失败：
';            echo '错误的SQL为'.$sql.'
';            echo '错误的代码为：',mysqli_errno($this->link),'
';            echo '错误的信息为：',mysqli_error($this->link),'
';            die();        }    }    /**     * @param $sql     * @return array|bool|null     */    //取单行数据    public function fetchRow($sql)    {        if($result = $this->query($sql))        {            $row = mysqli_fetch_array($result,MYSQLI_ASSOC);            return $row;        }        else        {            return false;        }    }    /**     * @param $sql     * @return array|bool     */    //取多行数据    public function fetchAll($sql)    {        if($result = $this->query($sql))        {            $rows = array();            while($row = mysqli_fetch_array($result,MYSQLI_ASSOC))            {                $rows[] = $row;            }            mysqli_free_result($result);            return $rows;        }        else        {            return false;        }    }    /**     * @param $data     * @return string     */    //防sql注入    public function escapeString($data)    {        return mysqli_real_escape_string($this->link,$data);    }    /**     * @param array $params     * @return mysqldb     */    //静态方法，获取实例    public static function getInstance($params=array())    {        if(!self::$instance instanceof self)        {            self::$instance = new self($params);        }        return self::$instance;    }    //复制    public function __clone()    {        die('禁止复制此类');    }}

过程：

index.php中，先引入init.php自动加载页面类，在调用model("emp_info")方法时，传入的是数据库中数据表的名称；

init.php中的model函数，在接收到调用时，先在传入的数据表名后加字符串“Model”，然后调用new，实例化emp_infoModel类；

为了能够自动加载类的代码，我们需要自己写一个加载函数my_autoload，此函数随意命名，传入的参数就是emp_infoModel，

由spl_autoload_register方法将加载函数my_autoload，注册至循环队列中,发生new class时，自动调用相应的页面代码进入；

emp_infoModel类继承自基类model,可以自动调用model父类中的方法，model类中使用mysqldb类的静态方法getInstance方法，获取数据库连接；

数据表emp_info:

CREATE TABLE `emp_info`  (  `emp_id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,  `emp_name` varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,  `emp_dept` varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,  `date_birth` timestamp(0) NOT NULL DEFAULT CURRENT_TIMESTAMP(0) ON UPDATE CURRENT_TIMESTAMP(0),  `date_entry` timestamp(0) NOT NULL,  PRIMARY KEY (`emp_id`) USING BTREE) INSERT INTO `emp_info` VALUES (1, '张三', '市场部', '1980-05-01 00:00:00', '2020-01-10 00:00:00');INSERT INTO `emp_info` VALUES (2, '李四', '人资部', '1980-05-01 00:00:00', '2020-01-10 00:00:00');INSERT INTO `emp_info` VALUES (3, '王五', '公关部', '1980-05-01 00:00:00', '2020-01-10 00:00:00');INSERT INTO `emp_info` VALUES (4, '麻六', '销售部', '1980-05-01 00:00:00', '2020-01-10 00:00:00');INSERT INTO `emp_info` VALUES (5, '小兰', '人事部', '1989-04-05 00:00:00', '2015-01-04 00:00:00');INSERT INTO `emp_info` VALUES (6, '小新', '广告部', '1993-08-19 00:00:00', '2016-02-24 00:00:00');INSERT INTO `emp_info` VALUES (7, '小白', '财务部', '1991-10-05 00:00:00', '2017-08-14 00:00:00');INSERT INTO `emp_info` VALUES (8, '小智', '运维部', '1978-11-25 00:00:00', '2000-03-19 00:00:00');INSERT INTO `emp_info` VALUES (49, 'x', 'd', '2020-09-01 00:00:00', '2020-09-02 00:00:00');