如何在php中的另一個類中導入數據庫連接類

Question

我要在Controller類中導入DatabaseConnector類。 DatabaseConnector類包含數據庫連接查詢。 這兩個類都是不同的php文件。

這是我的代碼。

DatabaseConnector：

class DatabaseConnector
{
    public $con;
    //function for getting connected to database
    public function getConnection()
    {
        $con=mysqli_connect("localhost","root","","abcd");
        // Check connection
        if (mysqli_connect_errno()) {
          echo "Failed to connect to MySQL: " . mysqli_connect_error();
        }
        return $con;
    }
    public function closeConnection()
    {
        mysqli_close($con);
    }
}

控制器：

include "database_connector.php";
    $dc = new DatabaseConnector();
    $con = $dc->getConnection();
class Controller
{

    public function __construct(){

    }

    public function insertData()
    {

        $name = "Abcde";
        $sql = "insert into user_details values('".$name."')";
        mysql_query($con, $sql);
    }


}

我在這段代碼中錯了。 它顯示mysql_query（$ con，$ sql）上的錯誤：$ con in undefined variable; 和mysql_query（）需要兩個參數

請幫我。

Answer 1

您的$con不在課程中。

include "database_connector.php";
class Controller
{
    protected $con;

    public function __construct(){
        $dc = new DatabaseConnector();
        $this->con = $dc->getConnection();
    }

    public function insertData()
    {
        $name = "Abcde";
        $sql = "insert into user_details values('".$name."')";
        mysqli_query($this->con, $sql);
    }
}

我沒有測試代碼，但這應該可行。