1

我什至不知道该怎么问。我一直在 C# 中这样做，但在我的一生中，我在 PHP 中找不到任何像样的示例。你能帮我吗？

例如，我正在尝试做的是。假设我有一个名为 Company 的班级，该班级有很多员工。

我希望能够将所有员工存储在公司类中，然后当我遍历 Company 对象时，我需要能够遍历分配给该公司的所有员工，并且我正在尝试找到一个直接的例子。

我可以填充它，但是从我的生活中我无法遍历员工。我知道我做错了什么，但无法弄清楚。这是我的例子。

员工

据我所知，这可能是完全错误的，因为要找回数据。

    class Employee
    {
        private $first;
        private $last;

        public function __construct($first = null, $last = null)
        {
            if(isset ($first))
                $this->first = $first;

            if(isset ($last))
                $this->last = $last;
        }

        public function getEmployee()
        {
            return Employee($this->first, $this->last);
        }

        public function getFirst()
        {
            return $this->first;
        }

        public function getLast()
        {
            return $this->first;
        }
    }

公司拥有一批员工。

在 c# 中，我会使用类似泛型的东西

    public List<Employee> Employees {get;set;}

然后在构造函数中我会做类似的事情

    Employees = new List<Employee>();

然后我可以做类似的事情

    foreach(var x in Customer.Employees)
            x.first;

这就是我想要做的。

    class Company
    {
        private $companyName;

        private $employees;


        public function __construct($nameOfCompany)
        {
            $this->companyName = $nameOfCompany;               
        }

        public function setEmployee(Employee $employee)
        {
            $this->employees[] = $employee;
        }

        public function getCompanyName()
        {
            return $this->companyName;
        }

        public function setCompanyName($nameOfCompany)
        {
            $this->companyName = $nameOfCompany;
        }

        public function getEmployees()
        {
            return $this->employees;
        }
    }

创建和填充

    $c = new Company("Test");
    $c->setEmployee(new Employee('A','B'));
    $c->setEmployee(new Employee('C','D'));
    $c->setEmployee(new Employee('E','F'));

到目前为止，一切都很好。

拿到公司的名字没问题。

    echo $c->getCompanyName();

    echo "<PRE>";
    print_r($c);
    echo "</PRE>";

但是我如何循环访问员工？

我希望能够做一些事情，比如将公司员工循环投射到单个员工，然后做类似的事情

    foreach(customers employees)
           echo Employee->getFirst, etc...

有人可以提供一些指导吗？

谢谢

4

3 回答 3

3

版本 1：显式 getter 方法

<?php
class Employee
{
  private $first;
  private $last;

  public function __construct($first = null, $last = null)
  {
    if(isset ($first))
    $this->first = $first;

    if(isset ($last))
    $this->last = $last;
  }

  public function getFirst()
  {
    return $this->first;
  }

  public function getLast()
  {
    return $this->first;
  }
}

class Company
{
  private $companyName;
  private $employees;

  public function __construct($nameOfCompany)
  {
    $this->companyName = $nameOfCompany;
  }

  public function addEmployee(Employee $employee)
  {
    $this->employees[] = $employee;
  }

  public function getCompanyName()
  {
    return $this->companyName;
  }

  public function getEmployees()
  {
    return $this->employees;
  }
}

$company = new Company('ACME');
$company->addEmployee(new Employee('A', 'A'));
$company->addEmployee(new Employee('B', 'B'));
$company->addEmployee(new Employee('C', 'C'));

foreach( $company->getEmployees() as $e ) {
  echo $e->getFirst(), "\n";
}

版本 2：使用__get

class Company
{
  private $companyName;
  private $employees;

  public function __construct($nameOfCompany)
  {
    $this->companyName = $nameOfCompany;
  }

  public function addEmployee(Employee $employee)
  {
    $this->employees[] = $employee;
  }

  public function __get($name) {
     // this will allow access to any member of the class
     // so you might want to test access first
     if ( isset($this->$name) ) {
       return $this->$name;
     }
   }

}

$company = new Company('ACME');
$company->addEmployee(new Employee('A', 'A'));
$company->addEmployee(new Employee('B', 'B'));
$company->addEmployee(new Employee('C', 'C'));

foreach( $company->employees as $e ) {
  echo $e->getFirst(), "\n";
}

$company = new Company('ACME');
$company->addEmployee(new Employee('A', 'A'));
$company->addEmployee(new Employee('B', 'B'));
$company->addEmployee(new Employee('C', 'C'));

foreach( $company->employees as $e ) {
  echo $e->getFirst(), "\n";
}
于 2010-08-02T00:13:18.350 回答
2 
foreach ($company->getEmployees() as $emp) {
    //do something with $emp
}

见foreach。

一注：

    public function __construct($first = null, $last = null)
    {
        if(isset ($first))
            $this->first = $first;

        if(isset ($last))
            $this->last = $last;
    }

完全一样

    public function __construct($first = null, $last = null)
    {
        $this->first = $first;
        $this->last = $last;
    }

因为没有初始化器的字段first和被初始化为。，在你的情况下，只检查参数是否为空，因为它保证被设置（它是一个参数）。lastnullisset

于 2010-08-02T00:10:51.240 回答
2

PHP 在语言中内置了称为 PHP 标准库的东西。PHP 标准库带有许多接口，允许您将某些核心语言功能实现到您自己定义的对象中。其中一个是迭代器接口。定义一个实现这个接口的类，然后编写一个实现，当它被放置在一个 foreach 循环中时，它允许你的对象做你想做的事情。

此外，根据您所追求的语义，您可以轻松地执行

foreach($company->getEmployees() as $employee)
{
    var_dump($employee);
}

该getEmployees方法只会被调用一次。

于 2010-08-02T00:14:47.277 回答