<?php
    define("HOSTNAME","127.0.0.1");
    define("USERNAME","root");
    define("PASSWORD","");
    define("DATANAME","class");


    /*
        作者：shyhero
        邮箱：shyhero@outlook.com
        Q  Q: 1757424878
     */
    require("./config.php");
    class Model{
        private $link;
        //构造函数，初始化数据库连接
        public function __construct(){
            $this -> link = mysqli_connect(HOSTNAME,USERNAME,PASSWORD,DATANAME) or die("数据库连接失败");
            mysqli_set_charset($this -> link,"utf8");
        }
        //查找               1.表名    2.条件  3.值     如果不添加条件或者值，就全部查询
        public function find($table="",$key="",$value=""){
            if(!$key||!$value){
                $sql = "select * from {$table}";
            }else{
                $sql = "select * from {$table} where {$key} = ‘{$value}‘";
            }
            $res = mysqli_query($this -> link,$sql);
            $arr = mysqli_fetch_all($res,MYSQLI_ASSOC);
            mysqli_free_result($res);
            return $arr;
        }
        //增加               1.表名   2.需要插入的字段  3.值1
        public function ins($table="",$zd="name,score",$value=""){
            $arr = explode(",",$value);
            $str = "";
            foreach($arr as $k => $v){
                $str .= "‘".$v."‘".",";
            }
            $str = rtrim($str,",");
            $sql = "insert into {$table}({$zd})values({$str})";
            $res = mysqli_query($this -> link,$sql);
            return mysqli_insert_id($this -> link);
        }
        //修改               1.表名  2.修改字段 3.值    4.条件   5.值
        public function upd($table="",$key="",$value="",$key2="",$value2=""){
            $sql = "update {$table} set {$key}=‘{$value}‘ where {$key2}=‘{$value2}‘";
            $res = mysqli_query($this -> link,$sql);
            return mysqli_affected_rows($this -> link);
        }
        //删除               1.表名   2.条件   3.值
        public function del($table="",$key="",$value=""){
            $sql = "delete from {$table} where {$key}=‘{$value}‘";
            $res = mysqli_query($this -> link,$sql);
            return mysqli_affected_rows($this -> link);
        }
        //析构函数
        public function __destruct(){
            if(isset($res))
                mysqli_free_result($res);
            mysqli_close($this -> link);
        }
    }
 
    $m = new Model();
    //var_dump($m -> find("stu","id"));
    var_dump($m -> ins("stu","name","zhu"));
    //var_dump($m -> upd("stu","name","dujianing","id","1"));
    //var_dump($m -> del("stu","name","li"));
 
?>