问题描述
如何在用户类中打开数据库连接，在那里进行数据库操作?以及为什么需要在 DBConnection 类中定义内置的创建函数..????
我已经创建了
- db.php
- user.php
- result.php
在 db.php
class DBConnection{受保护的 $mysqli;私人 $db_host="127.0.0.1";私人 $db_name="测试";私人 $db_username="root";私人 $db_password="";公共函数 __construct(){$this->mysqli=new mysqli($this->db_host,$this->db_username,$this->db_password,$this->db_name) 或 die($this->mysqli->error);返回 $this->mysqli;}public function query($query)//为什么我需要创建这个函数{返回 $this->mysqli->query($query);}公共函数 real_escape_string($str){返回 $this->mysqli->real_escape_string();}函数 __destruct(){//关闭连接$this->mysqli->close();}}?>在 User.php
mysqli=$conn;}公共函数 addUser($name,$username,$email,$pwd){$query="";$res=$this->mysqli->query($query);//请查一下DBConnection中的查询函数，需要定义什么查询>DBConnection 中的函数?返回 $res;}}?>在 result.php
<块引用>
$name = $conn->real_escape_string(trim(strip_tags($_POST['name'])));$username = $conn->real_escape_string(trim(strip_tags($_POST['username'])));$email = $conn->real_escape_string(trim(strip_tags($_POST['email'])));$password = $conn->real_escape_string(trim(strip_tags($_POST['pass'])));//echo $name."".$username."".$email."".$password;$uObj=新用户($conn);$uObj->addUser($name,$username,$email,$password);echo "你好，你的名字是<I>".$name."</I>并且你的电子邮件ID是<I>".$email."</I>";}?>你的 DBConnection 类需要一个额外的方法:
公共函数getLink(){返回 $this->mysqli;}看来您原来的 User 类是 DBConnection 的子类，因为 DBConnection 上的 mysqli 属性是protected 和 User 类有一个 parent::__construct() 调用.
最好使用依赖注入，这样您的 User 类将通过构造函数接收其数据库连接:
公共函数__construct(DBConnection $db){$this->mysqli = $db->getLink();}然后你可以从你的代码运行:
$db = 新的 DBConnection;$uObj = 新用户($db)；How can I open a database connection in user class , where I can do database operation? and why need to define inbuilt created functions in DBConnection class ..????
I have created
- db.php
- user.php
- result.php
in db.php
class DBConnection
{
protected $mysqli;
private $db_host="127.0.0.1";
private $db_name="test";
private $db_username="root";
private $db_password="";
public function __construct()
{
$this->mysqli=new mysqli($this->db_host,$this->db_username,
$this-> db_password,$this->db_name) or die($this->mysqli->error);
return $this->mysqli;
}
public function query($query) // why i need to creat this function
{
return $this->mysqli->query($query);
}
public function real_escape_string($str)
{
return $this->mysqli->real_escape_string();
}
function __destruct(){
//Close the Connection
$this->mysqli->close();
}
}
?>
in User.php
<?php
require "db.php";
class User {
public function __construct($conn)
{
$this->mysqli=$conn;
}
public function addUser($name,$username,$email,$pwd)
{
$query=" ";
$res=$this->mysqli->query($query);
//pls chek the query function in DBConnection,what is the need to define query > function in DBConnection ?
return $res;
}
}
?>
in result.php
<?php
require "user.php";
$conn=new DBConnection();
if(isset($_POST['submit']))
{
$name = $conn->real_escape_string(trim(strip_tags($_POST['name']))); $username = $conn->real_escape_string(trim(strip_tags($_POST['username']))); $email = $conn->real_escape_string(trim(strip_tags($_POST['email']))); $password = $conn->real_escape_string(trim(strip_tags($_POST['pass'])));
//echo $name."".$username."".$email."".$password;
$uObj=new User($conn);
$uObj->addUser($name,$username,$email,$password);
echo " hi your name is <I>".$name."</I> and your email ID is <I>".$email."</I>";
}
?>
Your DBConnection class would need an additional method:
public function getLink()
{
return $this->mysqli;
}
It seems that your original User class was a subclass of DBConnection, because mysqli property on DBConnection is protected and User class has a parent::__construct() call.
It's better to use dependency injection, so your User class will receive its database connection via the constructor:
public function __construct(DBConnection $db)
{
$this->mysqli = $db->getLink();
}
Then from your code you can run:
$db = new DBConnection;
$uObj = new User($db);
这篇关于如何访问另一个页面上另一个类中的mysqli连接?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持跟版网！