Question

我是使用PHP和Mysql数据库的新手。

我正在使用MAMP的phpmyadmin来创建数据库。

通过以下代码正常工作并建立与服务器的连接：

<?php
 include "config.php";

 $mysqli = new mysqli(DB_HOST, DB_USERNAME, DB_PASSWORD, DB_DATABASE);

 if (mysqli_connect_error()) {
  die('Connect Error ('.mysqli_connect_errno().') '.mysqli_connect_error());
 }

 echo 'Connected successfully.';


?>

但是，当我使用构造函数和类时，我遇到连接问题：

CONFIG.PHP：

<?php
    define("DB_HOST", "localhost");
    define("DB_USERNAME", "root");
    define("DB_PASSWORD", "root");
    define("DB_DATABASE", "scapik_users");
    define("DB_PORT","8889");
?>

DbConnect.php

<?php
include "config.php";

    class DbConnect{

        private $connect;

        public function __construct(){

            $this->connect = new mysqli(DB_HOST, DB_USERNAME, DB_PASSWORD, DB_DATABASE);

            if (mysqli_connect_error()) {
            die('Connect Error ('.mysqli_connect_errno().') '.mysqli_connect_error());
            }

        }

        public function getDb(){
            return $this->connect;
        }
    }
?>

有人可以帮我纠正代码，我想我错了。

感谢。

Answer 1

创建类

的对象

$ obj = new DbConnect（）;

然后运行你的代码

<?php 
include "config.php";


    class DbConnect{

        private $connect;

        public function __construct(){

            $this->connect = new mysqli(DB_HOST, DB_USERNAME, DB_PASSWORD, DB_DATABASE);

            if (mysqli_connect_error()) {
            die('Connect Error ('.mysqli_connect_errno().') '.mysqli_connect_error());
            } else {
            echo "connection successfull";
            }

        }

        public function getDb(){
            return $this->connect;
        }
    }
    $obj = new DbConnect();

?>

可能会帮助你。

Answer 2

尝试在构造函数中添加端口信息。由于您定义了它，可能需要连接到数据库，因为它可能只是在该端口上侦听。

使用完整的代码示例编辑我的答案 - 这可以在我这边工作

的config.php

<?php
define("DB_HOST", "localhost");
define("DB_USERNAME", "root");
define("DB_PASSWORD", "root");
define("DB_DATABASE", "test");
define("DB_PORT","3306");

DBConnect.php

<?php

include("config.php");

class DbConnect{
    private $connect;

    public function __construct(){
    $this->connect = new mysqli(DB_HOST, DB_USERNAME, DB_PASSWORD,         DB_DATABASE, DB_PORT);
    if (mysqli_connect_error()) {
        die('Connect Error ('.mysqli_connect_errno().') '.mysqli_connect_error());
    }
}

public function getDb(){
    return $this->connect;
}
}
$db = new DbConnect();
print_r($db->getDb());
?>

这对我来说很好......所以我猜你的代码很好。

我猜您已经检查过您的用户凭据以及端口和内容......？

您是否尝试过设置错误报告？

ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);

Answer 3

充分利用面向对象的编程。初始化DbConnect类时，请传递数据库参数。这将有助于您在整个课程中使用初始化变量。

<?php
include "config.php";

    class DbConnect{

        private $connect;
        private $host;
        private $username;
        private $password;
        private $database;
        public function __construct($host, $username, $password, $database){
            $this->host = $host;
            $this->username= $username;
            $this->password = $password;
            $this->database = $database;
            $this->connect = new mysqli($this->host, $this->username, $this->password, $this->database);

            if (mysqli_connect_error()) {
            die('Connect Error ('.mysqli_connect_errno().') '.mysqli_connect_error());
            }

        }

        public function getDb(){
            return $this->connect;
        }
    }
?>
<?php
    define("DB_HOST", "localhost");
    define("DB_USERNAME", "root");
    define("DB_PASSWORD", "root");
    define("DB_DATABASE", "scapik_users");
    define("DB_PORT","8889");
?>
<?php
$host = DB_HOST;
$username = DB_USERNAME;
$password = DB_PASSWORD;
$database = DB_DATABASE;

#call this class as:
$class = new DbConnect($host, $username, $password, $database);
?>

Php＆amp;数据库连接错误

3 个答案: