php基礎

データの型を確認

var_dump($msg);

定数

var_dump(__LiNE__);
var_dump(__FILE__);
var_dump(__DIR__);

文字列の連結

$s = "hello " . "world";

真偽値

$x = 5;
if ($x){
  echo "great";
}

三項演算子

$max = ($a > $b) ? $a : $b;

配列

$sales = array(
  "yama" => 200,
  "sato" => 400,
  "ito" => 600,
);
var_dump($sales["sato"]);

コロン構文

<ul>
<?php foreach ($colors as $value): ?>
  <li><?php echo "$value"; ?></li>
<?php endforeach; ?>
</ul>

クラス(オーバライドの禁止はメソッド名の前にfinalを付けます)

class User{
  public $name;
  public function __construct($name){
    $this->name = $name;
  }

  public function sayHi(){
    echo "hi, i am $this->name!";
  }
}

$tom =  new User("Tom");
$bob = new User("Bob");

echo $tom->name;
$bob->sayHi();

抽象クラス 

abstract class BaseUser{
  public $name;
  abstract public function sayHi();
}

class User extends BaseUser{
  public function sayHi(){
    echo "hello from user";
  }
}

インターフェイス

interface sayHi {
  public function sayHi();
}

interface sayHello {
  public function sayHello();
}

class User Implements sayHi, sayHello {
  public function sayHi{
    echo "hi";
  }
  public function sayHello{
    echo "hello";
  }
}