我在本地主機上運行這段代碼。在http://localhost:8000/Polymorphism.php上運行時出現錯誤。這是php上的一個簡單的多態代碼。其他代碼運行起來很輕松，但是運行這段代碼就出錯了。此頁面不工作本地主機當前無法處理此請求。HTTP 錯誤 500<?phppublic interface Shape{ public function calculateArea();} public class Circle implements Shape{ private $radius; public function __construct($r){ $this->radius=$r; } public function calculateArea(){ echo 'Area of circle = '.pi()* $this->radius*$this->radius.'<br>'; }}class Rectangle implements Shape{ private $height; private $width; public function __construct($h,$w){ this->height=$h; this->width=$w; } public function calculateArea(){ echo 'Area of a Rectangle=' .$this->height.$this->width.'<br>'; } } $circle= new Circle(5); $rect= new Rectangle(10,20); $circle->calculateArea(); $rect->calculateArea();?>
1 回答
藍山帝景
TA貢獻1843條經驗 獲得超7個贊
您永遠不會為類或接口分配訪問修飾符。它們僅用于指定方法和屬性。你在課堂上還有兩個錯誤，Rectangle你應該提到高度和寬度
$this->height=$h;
$this->width=$w;
將您的整體代碼更改為
<?php
interface Shape{
public function calculateArea();
}
class Circle implements Shape{
private $radius;
public function __construct($r){
$this->radius=$r;
}
public function calculateArea(){
echo 'Area of circle = '.pi()* $this->radius*$this->radius.'<br>';
}
}
class Rectangle implements Shape{
private $height;
private $width;
public function __construct($h,$w){
$this->height=$h;
$this->width=$w;
}
public function calculateArea(){
echo 'Area of a Rectangle=' .$this->height.$this->width.'<br>';
}
}
$circle= new Circle(5);
$rect= new Rectangle(10,20);
$circle->calculateArea();
$rect->calculateArea();
?>
- 1 回答
- 0 關注
- 107 瀏覽
添加回答
舉報
0/150
提交
取消