如何在 php 类中使用另一个文件

Question

我有两个文件 dbconnect.php 和 config.php

dbconnect.php

 <?php 
class connect{
    public function __construct(){
        $config = require_once __DIR__ . 'config.php';
    }

    private $dbhost = $config['host'];
    private $dbuser = $config['username'];
    private $dbpass = $config['pass'];
    private $dbname = $config['dbname'];

    public function startConn(){
        $this->DBcon = null;
        try{
            $this->DBcon = new PDO("mysql:host=".$this->dbhost.";dbname=".$this->dbname, $this->dbuser, $this->dbpass);
        }catch(Exception $e){
            echo "error connecting:";
        }
        return $this->DBcon;
    }
} 

?>

config.php

<?php

  /**
   * Contains all configurations
   *
  */
  return [
    'dbname' => 'user',
    'pass' => '@user.intern1',
    'username' => 'user1',
    'host' => 'localhost',
  ];
?>

在我的 dbconnect.php 文件中；
如何将 config.php 中的变量包含到连接类中

如果我按照上面的方式进行操作；
它对我大喊大叫并给我致命错误：
“解析错误：语法错误，第 8 行 C:\xampp\htdocs\hngfun\profile\adeojoemmanuel\php-handler\dbconfig.php 中的意外 '$config' (T_VARIABLE)”

Answer 1

我在这里猜测一下。但是我可以清楚地看到您将 $config 设置为构造函数中的局部变量。这意味着一旦您离开构造函数，它就无法使用。

<?php 
class connect{
    public function __construct(){
        $config = require_once __DIR__ . 'config.php';
        $this->dbhost = $config['host'];
        $this->dbuser = $config['username'];
        $this->dbpass = $config['pass'];
        $this->dbname = $config['dbname'];
    }

    private $dbhost ;
    private $dbuser ;
    private $dbpass ;
    private $dbname ;

    public function startConn(){
        $this->DBcon = null;
        try{
            $this->DBcon = new PDO("mysql:host=".$this->dbhost.";dbname=".$this->dbname, $this->dbuser, $this->dbpass);
        }catch(Exception $e){
            echo "error connecting:";
        }
        return $this->DBcon;
    }
} 

Answer 2

不能为private $dbhost 等声明的属性分配依赖于运行时数据的值，例如$config['host'];

引用PHP Docs:

这个声明可以包含一个初始化，但是这个初始化必须是一个常量值——也就是说，它必须能够在编译时被评估，并且不能依赖运行时信息才能被评估。

解决方案，在构造函数中赋值：

class connect{
    public function __construct(){
        $config = require_once __DIR__ . 'config.php';

        private $this->dbhost = $config['host'];
        private $this->dbuser = $config['username'];
        private $this->dbpass = $config['pass'];
        private $this->dbname = $config['dbname'];
    }

    private $dbhost;
    private $dbuser;
    private $dbpass;
    private $dbname;

    public function startConn(){
        $this->DBcon = null;
        try{
            $this->DBcon = new PDO("mysql:host=".$this->dbhost.";dbname=".$this->dbname, $this->dbuser, $this->dbpass);
        }catch(Exception $e){
            echo "error connecting:";
        }
        return $this->DBcon;
    }
} 

Answer 3

你需要在构造函数中设置：

private $dbhost;
private $dbuser;
private $dbpass;
private $dbname;

public function __construct(){
    $config = require_once __DIR__ . 'config.php';
    $this->dbhost = $config['host'];
    $this->dbuser = $config['username'];
    $this->dbpass = $config['pass'];
    $this->dbname = $config['dbname'];

}

Answer 4

第一个问题是您不能只从 config.php 文件中返回任何内容。您只能在函数内返回结果。实现这一点的一种方法是将数组声明为全局变量，然后在需要该配置数组的所有其他 php 文件中使用它。

<?php
/**
* Contains all configurations
*
*/
$dbconfig = array(
  'dbname' => 'user',
  'pass' => '@user.intern1',
  'username' => 'user1',
  'host' => 'localhost',
);
?>

<?php 
require_once __DIR__ . 'config.php';

class connect{
    public function __construct(){

    }

    private $dbhost = $dbconfig['host'];
    private $dbuser = $dbconfig['username'];
    private $dbpass = $dbconfig['pass'];
    private $dbname = $dbconfig['dbname'];

    public function startConn(){
        $this->DBcon = null;
        try{
            $this->DBcon = new PDO("mysql:host=".$this->dbhost.";dbname=".$this->dbname, $this->dbuser, $this->dbpass);
        }catch(Exception $e){
            echo "error connecting:";
        }
        return $this->DBcon;
    }
} 
?>