PHP变量在范围问题中丢失

Question

Simple data access layer program. I have a class with some protected variables for username password, etc. I have a function that reads the an INI file and fills those protected variables. like this

class SqlAdapter
{
    protected $_connection

    protected $_username
    protected $_passwprd
    protected $_hostname

    public function __construct()
    {
        $params = parse_ini_file(__file__, 1);
        $this->_username = $params[...][...];
        ...
        ...
        [where the problem comes in]
        $this->_connection = mysqli_connect($this_hostname, ..., ...);
    }

    public function fectchMyStuff()
    {
        $result array()
        $query = mysqli_query($connection, $query, MYSQLI_STORE_RESULT);

        while($row = mysqli_fetch_assoc($query))
        {
             $result[] = $row;
        }

        return json_encode($result);
    }

Now, when I run the connection stuff in the function it works just fine... but why isn't the protected variable "holding the charge" after the constructor is instantiated? Am I doingn something wrong?

Any advice? Point is, I don't want to have to rewrite that connection string every time I write a function that accesses my database... sort of defeats the purpose of reusable code and encapsulation and well, OOP all together!

thanks

Answer 1

Here was one approach I came up with... I don't know if this is good or right! :)

addeed:

public function connect()
{
    return $this->conn = mysqli_connect($this->server, $this->user, $this->pwd, $this->db); 
}

function fetchMyStucc
{
    $query = mysqli_query($this->connect(), $query, ...)

seems to work.

thanks for the advice! it helped