如何从config.php文件中读取值到另一个文件[关闭]

Question

I am new to coding with php and I need help with this.

I have a config.php file with these values

<?php
 define('DATABASE_HOST', 'localhost');
 define('DATABASE_NAME', 'voltrun');
 define('DATABASE_USERNAME', 'joy');
 define('DATABASE_PASSWORD', 'salty');
 ?>

I have also a db.php file with these values

<?php require_once"../config.php";
 echo 'DATABASE_HOST';
 echo 'DATABASE_NAME';
 echo 'DATABASE_USERNAME';
 echo 'DATABASE_PASSWORD'

  $db_host = 'DATABASE_HOST';
  $db_user = 'DATABASE_USERNAME';
  $db_password =  'DATABASE_PASSWORD';
  $db_database = 'DATABASE_NAME';

   $connection = mysqli_connect($db_host, $db_user, $db_password,    $db_database);

      if (!$connection) {
die('QUERY FAILED' . mysqli_error($connection));
   } 


   ?>

Any help on how to get the parameters from the config.php file into the db.php variables? As I still get Query Failed error.

Thanks for the help.

Answer 1

This part of your code:

 echo 'DATABASE_HOST';
 echo 'DATABASE_NAME';
 echo 'DATABASE_USERNAME';
 echo 'DATABASE_PASSWORD'
                         ^ missing ; if that's your actual code.

  $db_host = 'DATABASE_HOST';
  $db_user = 'DATABASE_USERNAME';
  $db_password =  'DATABASE_PASSWORD';
  $db_database = 'DATABASE_NAME';

You've wrapped all your constants in quotes, treating them as string literals; remove them.

Plus, you've a missing semi-colon:

 echo DATABASE_HOST;
 echo DATABASE_NAME;
 echo DATABASE_USERNAME;
 echo DATABASE_PASSWORD; // < Added the missing semi-colon

that error reporting would have thrown a parse error

  $db_host = DATABASE_HOST;
  $db_user = DATABASE_USERNAME;
  $db_password =  DATABASE_PASSWORD;
  $db_database = DATABASE_NAME;

References:

• http://php.net/manual/en/language.constants.php
• http://php.net/manual/en/language.types.string.php
• http://php.net/manual/en/function.error-reporting.php

Add error reporting to the top of your file(s) which will help find errors.

<?php 
error_reporting(E_ALL);
ini_set('display_errors', 1);

// rest of your code

Sidenote: Displaying errors should only be done in staging, and never production.

Also make sure that this is correct:

require_once"../config.php";

Error reporting will tell you that also.