php实现的简单数据库操作Model类

本文实例讲述了php实现的简单数据库操作Model类。分享给大家供大家参考，具体如下：该数

本文实例讲述了php实现的简单数据库操作Model类。分享给大家供大家参考，具体如下：

该数据库模型类可实现数据库的增删改查，简化数据库操作。

1. config.php代码：

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

2. 使用代码：

<?php
 /*
 作者：shyhero
 */
 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"));
?>