PHP面向對象實例（圖形計算器）

時間 2019-11-12

原文原文鏈接

效果：php

index.phphtml

<!DOCTYPE html>
<html>
<head>
    <title>圖形計算（使用面向對象技術開發）</title>
    <meta http-equiv="content" content="text/html" charset="utf-8" />
</head>
<body>
    <center>  <!--居中-->
        <h1>圖形（周長&面積）計算器</h1>
        <!--計算圖形的連接-->
        <a href="index.php?action=rect">矩形</a>||
        <a href="index.php?action=triangle">三角形</a>||
        <a href="index.php?action=circle">圓形</a>
        <hr>   <!--建立一條水平分隔線-->
    </center>

    <?php
        //錯誤報告處理
        //error_reporting(E_ALL & ~E_NOTUCE);
        //自動加載須要的類文件
        function __autoload($className){
            //strtolower()函數，把類名轉化爲小寫
            include strtolower($className).".class.php";
        }
        echo new Form();

        if(isset($_POST["sub"])){
            echo new Result();
        }
    ?>
</body>
</html>

form.class.phpide

<?php
class Form{
    private $action;
    private $shape;

    //在PHP5中的構造方法
    function __construct($action=""){
        $this->action=$action;
        $this->shape=isset($_REQUEST["action"])?$_REQUEST["action"]:"rect";
    }

    //在直接輸出對象引用的時候自動調用
    function __toString(){
        $form='<form action="'.$this->action.'" method="post">';
        //echo $this->shape;
        switch($this->shape){
            case "rect":
                //要加到表單裏面，要返回字符串
                $form.=$this->getRect();
                break;
            case "triangle":
                $form.=$this->getTriangle();
                break;
            case "circle":
                $form.=$this->getCircle();
                break;
            default:
                $form.='請選擇一個形狀<br>';
        }
        $form.='<input type="submit" name="sub" value="計算">';
        $form.='</form>';
        return $form;
    }

    //獲得矩形的方法
    private function getRect(){
        $input='<b>請輸入矩形的寬度和高度：</b><p>';
        $input.='寬度：<input type="text" name="width" value="'.$_POST["width"].'"><br>';
        $input.='高度：<input type="text" name="height" value="'.$_POST["height"].'"><br>';
        $input.='<input type="hidden" name="action" value="rect">';
        return $input;
    }
    //獲得三角形的方法
    private function getTriangle(){
        $input='<b>請輸入三角形的三條邊：</b><p>';
        $input.='第一條邊：<input type="text" name="side1" value="'.$_POST["side1"].'"><br>';
        $input.='第二條邊：<input type="text" name="side2" value="'.$_POST["side2"].'"><br>';
        $input.='第三條邊：<input type="text" name="side3" value="'.$_POST["side3"].'"><br>';
        $input.='<input type="hidden" name="action" value="triangle">';
        return $input;
    }
    //獲得圓形的方法
    private function getCircle(){
        $input='<b>請輸入圓形的半徑：</b><p>';
        $input.='半徑：<input type="text" name="radius" value="'.$POST["radius"].'"><br>';
        $input.='<input type="hidden" name="action" value="circle">';
        return $input;
    }
}
?>

shape.class.php函數

<?php
abstract class Shape{
    public $shapeName;
    abstract function area();
    abstract function perimeter();

    
    //驗證
    protected function validate($value,$message="形狀"){
        if($value==""||!is_numeric($value)||$value<0){
            echo '<font color="red">'.$message.'必須爲非負值的數字，而且不能爲空！</font><br>';
            return false;
        }else{
            return true;
        }
    }
}
?>

result.class.phppost

<?php
class Result{
    private $shape;

    function __construct(){
        switch ($_POST['action']) {
            case 'rect':
                $this->shape=new Rect();
                break;
            case 'triangle':
                $this->shape=new Triangle();
                break;
            case 'circle':
                $this->shape=new Circle();
                break;
            default:
                $this->shape=false;
                break;
        }
    }

    //在直接輸出對象引用的時候自動調用
    function __toString(){
        if($this->shape){
            $result=$this->shape->shapeName."的周長：".$this->shape->perimeter().'<br>';
            $result.=$this->shape->shapeName."的面積：".$this->shape->area().'<br>';
            return $result;
        }else{
            return "沒有這個形狀<br>";
        }
    }
}
?>

Rect.class.phpui

<?php
class Rect extends Shape{
    private $width=0;
    private $height=0;

    function __construct(){
        $this->shapeName="矩形";

        if($this->validate($_POST["width"],'矩形的寬') & $this->validate($_POST["height"],"矩形的長")){
        $this->width=$_POST["width"];
        $this->height=$_POST["height"];
        }else{
            exit;
        }

    }
    //面積
    function area(){
        return $this->width*$this->height;
    }
    //周長
    function perimeter(){
        return 2*($this->width+$this->height);
    }
}
?>

Triangle.class.phpthis

<?php
class Triangle extends Shape{
    private $side1=0;
    private $side2=0;
    private $side3=0;

    function __construct(){
        $this->shapeName="三角形";

        if($this->validate($_POST["side1"],'三角形的第一條邊') & $this->validate($_POST["side2"],"三角形的第二條邊") & $this->validate($_POST["side3"],"三角形的第三條邊")){
            $this->side1=$_POST["side1"];
            $this->side2=$_POST["side2"];
            $this->side3=$_POST["side3"];
            if(!$this->validateSum()){
                echo '<font color="red">三角形的兩邊之和必須大於第三邊！</font><br>';
                exit;
            }
        }else{
            exit;
        }
        
    }
    //海倫公式
    function area(){
        $s=($this->side1+$this->side2+$this->side3)/2;
        return sqrt($s*($s-$this->side1)*($s-$this->side2)*($s-$this->side3));
    }

    function perimeter(){
        return $this->side1+$this->side2+$this->side3;
    }


    //驗證兩邊之和大於第三邊
    private function validateSum(){
        $condition1=($this->side1 + $this->side2)> $this->side3;
        $condition2=($this->side1 + $this->side3)>$this->side2;
        $condition3=($this->side2 + $this->side3)>$this->side1;
        if($condition1 & $condition2 & $condition3){
            return true;
        }else{
            return false;
        }
    }
}
?>

Circle.class.phpspa

<?php
class Circle extends Shape{
    private $radius=0;

    function __construct(){
        $this->shapeName="圓形";

        if($this->validate($_POST["radius"],'圓的半徑')){
            $this->radius=$_POST["radius"];
        }else{
            exit;
        }
    }

    function area(){
        return pi()*$this->radius*$this->radius;
    }

    function perimeter(){
        return 2*pi()*$this->radius;
    }
}
?>