calling a function from php class

Question

i have witten this php class, but i have problem using it,

<?php
    class cs_mysql{
        protected $configPath;
        protected $db;
        function __construct($cP = null){
            $this->configPath = $cP;
            require $this->configPath;
        }
        private function connection(){
            $db = new mysqli(Config::get('dbHost'),Config::get('dbUser'),Config::get('dbPass'),Config::get('dbName'));
        }
        public function getRow($table){
            $query = 'SELECT * FROM $table ORDER BY `id` DESC';
            $sql = $this->db->query($query);
            if(!$sql){
                echo "FALSE";
            }
        }
    }
?>

i don't know how to run db query : $sql = $this->db->query($query);

But are you using `connection()` anywhere? I don't see you calling it. — Cave Johnson, Oct 25 '16 at 19:02
Based on this code, $db will always be null because `connection()` is never being run. — Brian, Oct 25 '16 at 19:03
Dupe: http://stackoverflow.com/questions/16959576/reference-what-is-variable-scope-which-variables-are-accessible-from-where-and — Marc B, Oct 25 '16 at 19:06

score 0 · Accepted Answer · answered Oct 25 '16 at 19:03

0

Change

$db = new mysqli(Config::get('dbHost'),Config::get('dbUser'),Config::get('dbPass'),Config::get('dbName'));

to

$this->db = new mysqli(Config::get('dbHost'),Config::get('dbUser'),Config::get('dbPass'),Config::get('dbName'));

$db is a property of the class. To access class properties (and methods) you have to reference the class instance using $this.

answered Oct 25 '16 at 19:03

DFriend

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i got this Error : Fatal error: Uncaught Error: Call to a member function query() on null in /Applications/XAMPP/xamppfiles/htdocs/bonbegir/bbadmin/classes/mysql.class.php:14 Stack trace: #0 /Applications/XAMPP/xamppfiles/htdocs/bonbegir/index.php(7): cs_mysql->getRow('category') #1 {main} thrown in /Applications/XAMPP/xamppfiles/htdocs/bonbegir/bbadmin/classes/mysql.class.php on line 14 – Amir Mohammad Rivand Oct 25 '16 at 19:10
@AmirMohammadRivand as I mentioned in my comment to your question, you are not calling `connection()` anywhere so `$this->db` will be null. You should call `$this->connection()` before you do `$this->db->query()` – Cave Johnson Oct 25 '16 at 19:19

calling a function from php class

1 Answers1