我在使用抽象类和OOP方面有点新手，所以请耐心等待。
我正在尝试制作员工和客户的列表，但我在打印 StoreList 类中的对象数组时遇到了一些麻烦，因为它们都受到保护。
我想做的是将storeArray中的值打印成一个漂亮的列表。
现在，它从抽象类的获取中打印出所有内容，使数组过时。
我将在下面包含所有代码，但由于它很长，我想在这里问这个问题。
这是我在索引或 Storelistclass 上var_dump数组时.php它时输出的内容.php
array (size=5)
0 =>
object(Employee)[1]
protected 'userId' => string '1' (length=1)
protected 'userFirstName' => string 'Joe' (length=3)
protected 'userLastName' => string 'Longo' (length=5)
protected 'userTitle' => string 'Employee' (length=8)
1 =>
object(Customer)[2]
protected 'userId' => string '1' (length=1)
protected 'userFirstName' => string 'Bruce' (length=5)
protected 'userLastName' => string 'Stark' (length=5)
protected 'userTitle' => string 'Customer' (length=8)
2 =>
object(Customer)[3]
protected 'userId' => string '2' (length=1)
protected 'userFirstName' => string 'Tony' (length=4)
protected 'userLastName' => string 'Wayne' (length=5)
protected 'userTitle' => string 'Customer' (length=8)
3 =>
object(Customer)[4]
protected 'userId' => string '3' (length=1)
protected 'userFirstName' => string 'Oliver' (length=6)
protected 'userLastName' => string 'Wilson' (length=6)
protected 'userTitle' => string 'Customer' (length=8)
4 =>
object(Customer)[5]
protected 'userId' => string '4' (length=1)
protected 'userFirstName' => string 'Slade' (length=5)
protected 'userLastName' => string 'Queen' (length=5)
protected 'userTitle' => string 'Customer' (length=8)
无论我在哪里尝试使foreach循环通过数组运行，我都会收到错误：无法访问受保护的属性。
foreach($this->storeArray as $data)
{
echo $data->userFirstName;
}
当我公开用户抽象类中的属性时，它工作得很好，但是 Get 会过时了吧？我应该放弃 Get 并将它们公开，还是有其他方法？
对不起，如果这是一个愚蠢的问题，但我真的试图解决这个问题并且失败了。
任何帮助和提示（也关于更新和删除功能）将不胜感激！
这就是我现在拥有的所有代码。
索引.php：
<?php
include("classes/Userclass.php");
include("classes/Customerclass.php");
include("classes/Employeeclass.php");
include("classes/Storelistclass.php");
$employeeOne = new Employee("1","Joe","Longo","Employee");
$customerOne = new Customer("1","Bruce","Stark","Customer");
$customerTwo = new Customer("2","Tony","Wayne","Customer");
$customerThree = new Customer("3","Oliver","Wilson","Customer");
$customerFour = new Customer("4","Slade","Queen","Customer");
$list = new Storelist($employeeOne);
$list->addCustomer($customerOne);
$list->addCustomer($customerTwo);
$list->addCustomer($customerThree);
$list->addCustomer($customerFour);
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<!--<link href="includes/stylesheet.css" rel="stylesheet" type="text/css"/>-->
<title>Store List</title>
</head>
<body>
<h1>Test Get Customer</h1>
<p>
<?php
echo $customerOne->getUserTitle()." #". $customerOne->getUserId() ."'s First name is ". $customerOne->getUserFirstName() ." and Last name is ". $customerOne->getUserLastName() ."<br/>";
echo $customerTwo->getUserTitle()." #". $customerTwo->getUserId() ."'s First name is ". $customerTwo->getUserFirstName() ." and Last name is ". $customerTwo->getUserLastName() ."<br/>";
?>
</p>
<h1>Test Get Employee</h1>
<p>
<?php
echo $employeeOne->getUserTitle()." #". $employeeOne->getUserId() ."'s First name is ". $employeeOne->getUserFirstName() ." and Last name is ". $employeeOne->getUserLastName() ."<br/>";
?>
</p>
<h1>Storelist Foreach</h1>
<p>
<?php
$listtest = $list->buildList();
echo $listtest;
?>
</p>
客户类别.php：
class Customer extends User
{
public function userSayHi()
{
return "Hello , could i get some help?";
}
}
员工类别.php：
<?php
class Employee extends User
{
public function userSayHi()
{
return 'Hello , how may i help u?';
}
}
用户类.php
<?php
abstract class User
{
protected $userId;
protected $userFirstName;
protected $userLastName;
protected $userTitle;
public function __construct($id, $firstName, $lastName, $title)
{
$this->userId = $id;
$this->userFirstName = $firstName;
$this->userLastName = $lastName;
$this->userTitle = $title;
}
//Gets
public function getUserId()
{
return $this->userId;
}
public function getUserFirstName()
{
return $this->userFirstName;
}
public function getUserLastName()
{
return $this->userLastName;
}
public function getUserTitle()
{
return $this->userTitle;
}
//Sets
public function setUserId($uId)
{
$this->userId = $uId;
}
public function setUserFirstName($ufirstName)
{
$this->userFirstName = $ufirstName;
}
public function setUserLastName($ulastName)
{
$this->userLastName = $ulastName;
}
public function setUserTitle($uTitle)
{
$this->userTitle = $uTitle;
}
public abstract function userSayHi();
}
存储列表类.php
<?php
require_once("Customerclass.php");
require_once("Employeeclass.php");
class Storelist
{
public $storeArray = [];
public function __construct(Employee $employee)
{
array_push($this->storeArray, $employee);
}
public function addCustomer(Customer $customer)
{
array_push($this->storeArray, $customer);
//return $this->storeArray;
}
public function buildList()
{
foreach($this->storeArray as $storeData)
{
echo "First Name: ".$storeData->getUserFirstName()."<br/>";
echo "Last Name: ".$storeData->getUserLastName()."<br/>";
echo "Is a: ".$storeData->getUserTitle()."<br/>";
echo "<br/>";
}
/*
//ERROR : Cannot access protected property Employee::$userFirstName
foreach($this->storeArray as $storeData)
{
echo "First Name: ".$storeData->userFirstName."<br/>";
echo "Last Name: ".$storeData->userLastName."<br/>";
echo "Is a: ".$storeData->userTitle."<br/>";
echo "<br/>";
}
*/
}
public function delete()
{
}
public function update()
{
}
}
解决方案是实际使用您已经不厌其烦地定义的getter方法（getUserWhatever()）。 通过保持它们protected可见性，除了使用您定义的setUserWhatever()方法之外，无法修改它们，因此您可以执行其他验证（例如防止非空值）并对无效数据引发异常。 因此，它们不像public属性那样可以直接从类外部可变，这是很有用的。
在 Storelist 类中，您已经定义了具有public可见性的 $storeArray 属性，这意味着您可以在 index.php 中读取它在类外部。 由于您要向该数组添加Employee或Customer对象，因此这些对象仍可通过其在 $list->storeArray 上的数组键单独寻址。 因此，例如要修改姓氏，您可以使用
// Set the 3rd user's last name
$list->storeArray[2]->setUserLastName('Jones');
同样，在 Storelist 类中使用 $this 也可以这样做：
// Inside Storelist
$this->storeArray[2]->setUserLastName('Jones');
因此，您已经对这些类的布局进行了基本了解。 我还可以建议一件事;由于您已经创建了方法来使用方法调用添加Customer或Employee对象以Storelist::$storeArray，而不是直接修改数组：
// You're doing this:
$list = new Storelist($employeeOne);
$list->addCustomer($customerOne);
// And not this (directly modifying storeArray):
$list = new Storelist($employeeOne);
$list->storeArray[] = $customerOne
。然后，还考虑将 Storelist::$storeArray 定义为 protected 属性，以便只能使用其 setter 方法写入它。然后，您还需要创建一个返回数组的 getter 方法。
class Storelist
{
// This becomes protected
protected $storeArray = [];
// So you need a getter:
public function getStoreArray()
{
return $this->storeArray;
}
// etc...
}
要从index.php修改数组，则无法再直接读取其元素。相反，你称之为getter方法：
// You can't do this:
$list->storeArray[2]->setUserLastName('Jones');
// Instead do it via the getter:
$list->getStoreArray()[2]->setUserLastName('Jones');
（注意，上面的()[2]语法需要 PHP 5.4+）