How to instantiate $Pdo = connect() without repeating?

Question

For example I have a class called user:

class User
{
    public $nome;
    private $email;
    protected $senha;

    public function __construct(){

    }

    public function insert($email, $senha){
        require_once "conexao.php";
        $pdo = conectar();

        $insertSQL = $pdo->prepare('INSERT INTO tbl (valores) VALUES (?)');
        $insertSQL->bindValue(1, $this->lalala(), PDO::PARAM_STR);
        $insertSQL->execute();
    }

and also see that I need to do the require():

require_once "conexao.php";
$pdo = connect();

But I have to do these two lines every time for every method in the class. There is no way to create a single time and be available in all class scope, like attributes?

I’ve tried as an attribute and it didn’t work. With the constructor it wasn’t either (maybe I did wrong).

Answer 1

A suggestion is to create a property and connection in your class and pass the connection to it via constructor. So whenever the object (from User) need a connection it will already be open.

class User
{
    public $nome;
    private $email;
    protected $senha;
    private $db; //propriedade da conexão

    //pega a conexão externa e joga dentro da propriedade
    public function __construct($db){
       $this->db = $db;
    }

    public function insert($email, $senha){
       $insertSQL = $this->db->prepare('INSERT INTO tbl (valores) VALUES (?)');
       //demais códigos ...
}

When it’s time to call

include 'conexao.php'; 
$user = new User($pdo);

//ou ainda:
$user = new User(conectar());

It does not have much advantage to create a function only to create and return the PDO connection with the user parameters and direct password in the code, in this case you can pass the direct connection variable.

Answer 2

You can do it this way:

require_once "conexao.php";

class User
{
    public $nome;
    private $email;
    protected $senha;

    public function __construct(){

    }

    public function insert($email, $senha){
        $pdo = conectar();

        $insertSQL = $pdo->prepare('INSERT INTO tbl (valores) VALUES (?)');
        $insertSQL->bindValue(1, $this->lalala(), PDO::PARAM_STR);
        $insertSQL->execute();
    }