PHP?? ??? ???? ????, ??? ? ?? ?? ??? ? ??????

??? ??(DI)? ????? ???? ?? ???, ??? ??? ? ?? ???? ????? ?? ???? ??? ?????. ?? PHP? ??? ?? ?? ?????(OOP)?? ?? ?????. DI? ???? ???? ????? ???? ?? ?? ???? ???(?, ???? ? ??? ??)? ?? ? ????. ?? ???? ????? ???? ?? ????? ?? ?? ? ??? ??? ?????? ?????.

? ????? ??? ??? ????, PHP?? ??? ?????, ?? ?? ? ??? ??? ?? ??? ??? ??? ???????.

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1. ??? ???? ??????

??? ???? ???? ??? ?? ??? ???(?? ???)? ???? ?? ???? ?? ??? ???? ???? ????? ????. ??? ???? ???? ??? ???? ? ??? ?????? ??, ??? ?? ?? ?????? ?? ??? ? ????.

?? ?? ?? ??????? ???? ??? ???? ??? ?? ?????? ? ???? ?? ???? ???? ?????. ?? ?? ??, ???, ??? ??? ??? ?? ? ????.

??? ??? ???? ???? ???? ???? ??? ??? ??? ?????. ??? ?? ???? ? ?? ???? ??? ? ???? ??? ?? ????? ?????? ?????.

??? ?? ??

DatabaseConnection ???? ???? DatabaseService ???? ??? ?? ??? ?? ??? ???.

??? ?? ??(??? ??):

class DatabaseService {
    private $dbConnection;

    public function __construct() {
        $this->dbConnection = new DatabaseConnection(); // Creates its own dependency
    }

    public function fetchData() {
        // Uses the database connection to fetch data
        return $this->dbConnection->query('SELECT * FROM users');
    }
}

? ??? DatabaseService ???? ?? DatabaseConnection ????? ?????. ?? ?? DatabaseConnection? ?? ???? ????? ??? ???? ????? ?????.

??? ??(??? ??) ??:

class DatabaseService {
    private $dbConnection;

    // Dependency is injected through the constructor
    public function __construct(DatabaseConnection $dbConnection) {
        $this->dbConnection = $dbConnection; // Dependency is passed in
    }

    public function fetchData() {
        // Uses the injected database connection to fetch data
        return $this->dbConnection->query('SELECT * FROM users');
    }
}

? ??? ??? DatabaseService ???? DatabaseConnection ????? ???? ????. ?? DatabaseConnection ??? ???? ?????(???? ???). ??? ?? ???? ? ????? DatabaseConnection? ?? ??? ?????. ?? DatabaseConnection? ?? ??? ?? ?????? ???? ?? ?? ? ????.

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2. PHP? ??? ?? ??

??? ??? ???? ? ?? ?? ??? ??? ????.

1. ??? ??: ???? ???? ?? ???? ?????. ?? ??? ??? ?? ????? ???? ?????.

class DatabaseService {
    private $dbConnection;

    public function __construct() {
        $this->dbConnection = new DatabaseConnection(); // Creates its own dependency
    }

    public function fetchData() {
        // Uses the database connection to fetch data
        return $this->dbConnection->query('SELECT * FROM users');
    }
}

1. Setter ??: ???? setter ???? ?? ?????. ? ??? ??? ??? ? ???? ????? ?? ????? ??? ??? ????? ?? ? ????.

class DatabaseService {
    private $dbConnection;

    // Dependency is injected through the constructor
    public function __construct(DatabaseConnection $dbConnection) {
        $this->dbConnection = $dbConnection; // Dependency is passed in
    }

    public function fetchData() {
        // Uses the injected database connection to fetch data
        return $this->dbConnection->query('SELECT * FROM users');
    }
}

1. ????? ??: ???? ???? ???? ??? ???? ?????? ?????. ? ??? ? ????? ????? ??? ?? ?????? ????? ????? ?? ???? ??? ? ????.

   class SomeClass {
       private $service;

       public function __construct(Service $service) {
           $this->service = $service;
       }
   }

3. ??? ??? ??

?. ??? ???

DI? ??? ??? ???? ???? ?? ???? ?????? ???? ?? ???? ?????. ??? ?? ??? ???? ??? ?? ?? ???? ?? ????? ??? ? ????. ??? ??? ???? ?? ???? ?? ????? ???????.

?. ??? ??? ???

?? ???? ?? ?? ?? ?? ??? ??? ? ???? ??? ??? ???? ???? ?? ?????. ?? ??? ?? ???? ??? ????? ?? ???? ?? ?????.

?? ?? DatabaseService ???? ?????? ?? ?????? ??? ??????? ?? ?????? ??? ???? ??? ?? ?? ?????? ??? ???? ????.

   class SomeClass {
       private $service;

       public function setService(Service $service) {
           $this->service = $service;
       }
   }

?. ?? ??? ?? ?? ? ????

??????? ???? ?? ????? ??? ???. DI? ???? ???? ???? ???? ??? ???? ????? ?? ????. ?? ???? ???? ??? ???? ??????? ??? ? ???? ??? ???? ?? ???? ? ?? ??? ? ????.

?. ???? ????

???? ?? ???? ??? ?? ?? ???? ??? ???? ???? ? ????. ?? ??, DatabaseService ???? ??? ?? ?????? ?? ??? ???? ?? ?????? ??(?: MySQL, PostgreSQL, SQLite)? ?? ??? ? ????.

e. ??? ??

??? ?????? ??? ? ???? ???? ???? ?? ??? ? ????. PHP-DI ?? Symfony ??? ??? ?? DI ?????? ??? ??? ????? ???? ??????? ??? ?? ?? ???? ?? ?? ?????? ?? ??? ? ????.

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4. ??? ?? ????

??? ?? ????(?? DI ????)? ??? ?? ? ??? ???? ???? ??? ?????. ????? ??? ? ??? ????, ??? ? ??? ???????, ???? ????, ?? ????? ???? ? ??? ? ????.

???? PHP DI ????? Symfony? ??? ?? ???????. ?? ??? ?? ??? ????.

class DatabaseService {
    private $dbConnection;

    public function __construct() {
        $this->dbConnection = new DatabaseConnection(); // Creates its own dependency
    }

    public function fetchData() {
        // Uses the database connection to fetch data
        return $this->dbConnection->query('SELECT * FROM users');
    }
}

? ??? DI ????? DatabaseService ??? ???? db_connection ???? ???? ?????.

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5. ??? ? ?? ?? ??? ??? ??? ??? ??? ??????

?. ?? ??? ???

??? ??? ???? ??? ?? ?? ???? ??? ? ???? ?? ???? ? ?????. DI? ??? ?? ???? ?? ??(?: ?????? ??, ?? I/O)? ???? ?? ?????? ???? ????? ????? ??? ????.

?. ?? ?? ??

DI? ??? ?? ? ??? ?? ????? ?? ??? ????. ? ???? ????? ???? ? ????? ???? ?? ? ? ???? ??? ??? ?????.

?. ?? ??? ??

DI? ?? ??? ?? ???? ?? ???? ???? ? ????. ???? ??? ???? ??? ?? ???? ????? ????? ??? ? ?? ?? ????? ???? ? ????.

?. ??? ??? ?????

??? ??? ?? SOLID ??, ?? ?? ?? ??(SRP) ? ??? ?? ??(DIP)? ? ????. ???? ???? ???? ???? ???? ??? ???? ??? ? ?? ???? ?? ??? ? ????.

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6. ??

??? ??? ??? ?? ?? ???, ??? ??? ? ???? ????? ? ??? ?? PHP? ?? ??? ?????. ???? ?? ????? ?????? DI? ?? ?? ???(?? ??? ??)? ? ? ???(???? ?? ???? ??)? ?????.

?? PHP ??????? ?? DI? ???? ?? ??? ? ????? ???? ???? ?? ??? ??? ??? ??? ? ?? ?????. DI? ???? ???? DI ????? ???? ? ??? ???? PHP ????? ??? ??? ?? ?????.

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? ??? PHP? ??? ???? ???? ??? ? ?? ??? ??? ??? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!