6 ways to create objects in PHP

Create object instance:

<?php
/**
 * PHP创建对象的六种方式
 */
class Person{
  private $name = &#39;bruce&#39;;
  public function getName(){
    return $this->name;
  }
  public static function getObjBySelf(){
    return new self();
  }
  //动态延迟绑定，能识别调用者
  public static function getObjcByStatic(){
    return new static();
  }
}
//Person子类 Teacher
class Teacher extends Person{
  public static function getObjByParent(){
    return new parent();
  }
}

//1、new 类名();创建对象
$obj1 = new Person();//等价于写法 $obj1 = new Person;
echo &#39;类名：&#39;.get_class($obj1).&#39;<br>&#39;;
echo $obj1->getName().&#39;<hr>&#39;;

//2、将类名字符串赋值给一个变量，通过变量创建
$clsName = &#39;Person&#39;;
$obj2 = new $clsName();
echo &#39;类名：&#39;.get_class($obj2).&#39;<br>&#39;;
echo $obj2->getName().&#39;<hr>&#39;;

//3、通过对象实例创建对象
$obj3 = new $obj2();
echo &#39;类名：&#39;.get_class($obj3).&#39;<br>&#39;;
echo $obj3->getName().&#39;<hr>&#39;;

//4、通过 new self()
//$obj4 = (new $obj3())->getObjBySelf();
$obj4 = Person::getObjBySelf();
echo &#39;类名：&#39;.get_class($obj4).&#39;<br>&#39;;
echo $obj4->getName().&#39;<hr>&#39;;

//5、通过 new parent()
$obj5= Teacher::getObjByParent();
echo &#39;类名：&#39;.get_class($obj5).&#39;<br>&#39;;
echo $obj5->getName().&#39;<hr>&#39;;

//6、通过 new static();
$obj6 = Person::getObjcByStatic();
echo &#39;类名：&#39;.get_class($obj6).&#39;<br>&#39;;//类名：Person
echo $obj6->getName().&#39;<hr>&#39;; //bruce
//当用子类去调用时候，发现static自动识别当前调用者（静态延迟绑定），返回当前调用者对象
$obj7 = Teacher::getObjcByStatic();
echo &#39;类名：&#39;.get_class($obj7).&#39;<br>&#39;;//类名：Teacher
echo $obj7->getName().&#39;<hr>&#39;;//bruce
$obj8 = Person::getObjBySelf();
echo &#39;类名：&#39;.get_class($obj8).&#39;<br>&#39;;//类名：Person
echo $obj8->getName().&#39;<hr>&#39;;
//new self()在子类中调用依旧返回原来父类的绑定
$obj9 = Teacher::getObjBySelf();
echo &#39;类名：&#39;.get_class($obj9).&#39;<br>&#39;;//类名：Person
echo $obj9->getName().&#39;<hr>&#39;;

Run result:

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