PHP 依賴注入

zengdongbao 發(fā)布于2019-07-01 10:59 / 1341人閱讀

摘要：通常調(diào)用一個(gè)類里面的方法需要如何操作依賴注入模式用來(lái)減少程序間的耦合依賴注入共有三種模式方法注入著重說(shuō)下方法注入并結(jié)合單例注冊(cè)的服務(wù)數(shù)組訪問(wèn)接口測(cè)試郵件發(fā)送成功方式訪問(wèn)通過(guò)數(shù)組的方式訪問(wèn)也是通過(guò)該方式實(shí)現(xiàn)依賴

通常調(diào)用一個(gè)類里面的方法需要如何操作：

$class = new class();
$class->fun()

依賴注入模式用來(lái)減少程序間的耦合

依賴注入共有三種模式： setter 方法注入

著重說(shuō)下setter方法注入并結(jié)合ArrayAccess

/**
 * Class Di
 * @property People
 */
class Di implements ArrayAccess
{
    /**
     * 單例
     * @var null
     */
    protected static $instance = null;

    /**
     * 注冊(cè)的服務(wù)
     * @var array
     */
    protected $data = array();

    public function __construct()
    {
        echo "__construct". "
";
    }

    public function onConstruct(){
        echo "onConstruct". "
";
    }

    public static function one(){
        if (self::$instance == null) {
            self::$instance = new Di();
            self::$instance->onConstruct();
        }
        return self::$instance;
    }

    public function get($name, $default = NULL) {
        if (!empty($default)) {
            return $default;
        }

        return $this->data[$name];
    }

    public function set($name, $value) {
        $this->data[$name] = $value;
    }

    public function __get($name)
    {
        return $this->get($name);
    }

    public function __set($name, $value)
    {
        $this->set($name, $value);
    }


    /** ArrayAccess數(shù)組訪問(wèn)接口 **/

    public function offsetSet($offset, $value) {
        $this->set($offset, $value);
    }

    public function offsetGet($offset) {
        return $this->get($offset, NULL);
    }

    public function offsetUnset($offset) {
        unset($this->data[$offset]);
    }

    public function offsetExists($offset) {
        return isset($this->data[$offset]);
    }

}

class People {

    protected $name = "測(cè)試";
    public function getName(){
        return $this->name;
    }

}

class Email {

    public function sendEmail($email){
        return "郵件發(fā)送成功！";
    }

}

$di = Di::one();
/** @var get set 方式訪問(wèn) people */
$di->people = new People();
$people = $di->people;
echo $di->people->getName();

/** 通過(guò)數(shù)組的方式訪問(wèn) **/
$di["Email"] = new Email();
echo $di["Email"]->sendEmail("[email protected]");

Phalapi也是通過(guò)該方式實(shí)現(xiàn)依賴注入 
依賴注入相當(dāng)于一個(gè)注冊(cè)中心，通過(guò)魔術(shù)方法__set __get進(jìn)行賦值和取之操作，$di->email
implements ArrayAccess 可以實(shí)現(xiàn)通過(guò)數(shù)組的方式進(jìn)行操作$di["Email"]

構(gòu)造方法注入

通過(guò)__construct出入類

class a
{
    public function test() {
        echo "test";
    }
}

class c
{
    protected $s;
    public function __construct($a)
    {
        $this->s = $a;
    }

    public function test(){
        $this->s->test();
    }
}

$a = new a();
$c = new c($a);
$c->test();

接口注入

interface sql{

    public function connect();
    public function query();
}


class mysql implements sql {

    public function connect()
    {
        echo "連接mysql成功". "
";
    }

    public function query()
    {
        // TODO: Implement query() method.
    }
}

class sqlServe implements sql {

    public function connect()
    {
        echo "連接sqlServe成功". "
";
    }

    public function query()
    {
        // TODO: Implement query() method.
    }
}

class Demo{

    public $sql;

    public function __construct(sql $sql)
    {
        $this->sql = $sql;

    }
}

$mysql = new mysql();
$sqlServe = new sqlServe();

(new Demo($mysql))->sql->connect();