Prepared statements and class inheritance in PHP -

i have problem when doing prepared statement in php. main goal create 2 classes, first 1 connecting (conexion) server , database , second 1 prepared statements (realizarconsultas).

i have decided class used statements should inherit "conexion". doing pretend connect database each time use function "realizarconsultas::mostrarconsulta()". function should connect database, should prepared statement , should close connection.

class used connection.

<?php      class conexion extends pdo{          protected $conexiondb;          public function conexion(){              try{                 $conexiondb=new pdo ('mysql:host=localhost;dbname=euroburo','root','');                 $conexiondb->setattribute(pdo::attr_errmode, pdo::errmode_exception);                 $conexiondb->exec("set character set utf8");                }catch(exception $e){                  echo "error: ".$e->getline();              }         }         public function stopconexion(){             $conexiondb->close();         }      } ?> 

class used prepare statements.

<?php     require("conexion.php");     class realizarconsulta extends conexion{         public function realizarconsulta(){             parent::__construct();         }         public function mostrarconsulta($consulta){             $resultado=$this->conexiondb->prepare($consulta);             $resultado->execute();             $final = $resultado->fetch(pdo::fetch_assoc);               print_r($final);             $this->stopconexion();         }     }  ?> 

my main problem in line, located inside "realizarconsulta::mostrarconsulta()".

$resultado=$this->conexiondb->prepare($consulta); 

each time call function (realizarconsulta::mostrarconsulta());

this error appears: call member function prepare() on non-object.

i understand error tells me $this->conexiondb not object don't understand why. reason don't understand error due fact $conexiondb protected variable created in parent class, protected variable "realizarconsulta" class should inherit without problem , should have access it. $conexiondb can see initialised when constuctor called, , should hold information related connection.

as can see through reasoning, $conexiondb should reference object belongs "conexion" class , should have access in "realizarconsulta" class.

i know in failing , how can resolve error. thanks

you're declaring class level variable, unless you're leaving out code, you're not assigning local variable class level. in php, have that. example

class {     protected $a;      public function __construct() {         $this->a = 'hello';     }      public function echo() {         $a = 'world';         echo $this->a . ' ' . $a;     } }  $a = new a(); $a->echo() 

would echo hello world. because in echo(), $a local variable, , $this->a variable scoped class. they're 2 different variables hold 2 different values.

so constructor should this

    public function __construct() {          try {             $conexiondb= new pdo('mysql:host=localhost;dbname=euroburo', 'root', '');             $conexiondb->setattribute(pdo::attr_errmode, pdo::errmode_exception);             $conexiondb->exec("set character set utf8");             $this->conexiondb = $conexiondb;         } catch(exception $e) {             echo "error: ".$e->getline();         }     } 

also, side note, it's highly recommended use public function __construct() constructor in php, not function same name class