<?php
 
Class Usuario 
{
    private $pdo;
    public $msgErro;
 
    public function conectar($nome, $host, $usuario, $senha){
         global $pdo;
         try 
         {
             $pdo = new PDO("mysql:dbname=".$nome.";host=".$host,$usuario,$senha);
         }
         catch (PDOException $e)
         {
            $this->msgErro = $e->getmessage();
        }
    }
}
 
$u = new Usuario();
$u->conectar('a','d','f','r');
 
echo 'Erro: '.$u->msgErro;

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