调用我的对象及其函数

Question

我是 php 的新手，正在尝试使用工厂方法。我想使用 'build' 函数实例化我的 class 形状，这样当实例化 class 'Circle' 时计算其面积和周长，如果 class 'Rectangle' 被调用，它的面积和周长被计算并返回。这就是我目前所拥有的和我想要的 achieve.This 不起作用，我相信有更好的方法来做到这一点！

$allmyshapes = Shapes::build($initData);
 foreach($allmyshapes as $value) { 
  if ($value =='Circle'){
   $x = new Circle();
   echo $x::area();
   echo $x::circumference();
}
 if ($value =='Rectangle'){
   $y = new Rectangle();
   echo $y::area();
   echo $y::circumference();

}

}

我的Class:

class Shapes {
  public static function build($initData){

    }
    foreach($newlist as $value){
       if($value[0]=='Circle'){
          $shape1 =new Circle($value[1],$value[2]);
        }
       if($value[0]== 'Rectangle'){
         $shape2 =new Rectangle($value[1],$value[2]); 
        }

    }
     return array($shape1,$shape2);
  }

}

class Circle extends Shapes {
  public $radius;
  public $centre_point;
  public function __construct($radius, $centre_point) {
    $this->radius = $radius;
    $this->centre_point = $centre_point;
  }
  public function area(){
    return (pi() *$this->radius * $this->radius);
  }
  public function circumference(){
    return 2 * pi() *$this->radius;
  }

 }

class Rectangle extends Shapes {
  public $x;
  public $y;
  public function __construct($x, $y) {
    $this->x= $x;
    $this->y = $y;
  }
  public function area() {
    return $this->x * $this->y;
  }
  public function circumference() {
    return 2 * ($this->x+ $this->y);
  }

}

Answer 1

你的类没问题，就是你用它们输出信息的方式：

class Shapes {
    public static function build($initData){
        //$initdata is a heredoc
        $newlist = explode("\n", $initData);
        foreach($newlist as $key => $initData){
            $newlist[$key] = explode("\t", $initData);
        }
        foreach($newlist as $value){
            if($value[0] == 'Circle'){
                $shape1 = new Circle($value[1], $value[2]);
            }
            if($value[0] == 'Rectangle'){
                $shape2 = new Rectangle($value[1], $value[2]);
            }
        }
        return array($shape1, $shape2);
    }
}

class Circle extends Shapes {
    public $radius;
    public $centre_point;
    public function __construct($radius, $centre_point){
        $this->radius = $radius;
        $this->centre_point = $centre_point;
    }
    public function area(){
        return (pi() * $this->radius * $this->radius);
    }
    public function circumference(){
        return 2 * pi() * $this->radius;
    }
    public function draw(){
        return ( $this->radius.":".$this->centre_point);
    }
}

class Rectangle extends Shapes {
    public $x;
    public $y;
    public function __construct($x, $y){
        $this->x = $x;
        $this->y = $y;
    }
    public function area(){
        return $this->x * $this->y;
    }
    public function circumference(){
        return 2 * ($this->x + $this->y);
    }
}

$initData = <<<ENDINIT
Circle  5   2
Rectangle   5   10
Ellipse 10 10   4   5
ENDINIT;
$allmyshapes = Shapes::build($initData);
foreach($allmyshapes as $value){
    if(get_class($value) === 'Circle'){
        echo nl2br("**Circle**\nArea: ".$value->area()."\nCircumference: ".$value->circumference()."\n");
    }
    if(get_class($value) === 'Rectangle'){
         echo nl2br("**Rectangle**\nArea: ".$value->area()."\nCircumference: ".$value->circumference()."\n");
    }
}

我在您提供的代码中添加了 2 个函数，get_class() & nl2br()。如果您以 CLI 格式使用它，则可以删除 nl2br，但它的主要功能是在使用 Web 浏览器查看输出时提高输出可读性。

get_class() 将解决您试图弄清楚在创建对象时使用了哪个构造函数的问题。

调用我的对象及其函数

Calling my objects and its functions

php

class

instantiation