在 php 中获取设置属性

get set properties in php

提问by Jeppe Str?m

I'm from the C# environment and I'm starting to learn PHP in school. I'm used to set my properties in C# like this.

我来自 C# 环境，我开始在学校学习 PHP。我习惯于像这样在 C# 中设置我的属性。

public int ID { get; set; }

What's the equivalent to this in php?

php 中的 this 等价于什么？

Thanks.

谢谢。

回答by Mchl

There is none, although there are some proposals for implementingthat in future versions. For now you unfortunately need to declare all getters and setters by hand.

没有，尽管有一些建议在未来版本中实现。不幸的是，现在您需要手动声明所有 getter 和 setter。

private $ID;

public function setID($ID) {
  $this->ID = $ID;
}

public function getID() {
  return $this->ID;
}

for some magic (PHP likes magic), you can look up __setand __getmagic methods.

对于一些魔法（PHP喜欢魔法），您可以查找__set和__get魔术方法。

Example

例子

class MyClass {

  private $ID;

  private function setID($ID) {
    $this->ID = $ID;
  }

  private function getID() {
    return $this->ID;
  }


  public function __set($name,$value) {
    switch($name) { //this is kind of silly example, bt shows the idea
      case 'ID': 
        return $this->setID($value);
    }
  }

  public function __get($name) {
    switch($name) {
      case 'ID': 
        return $this->getID();
    }
  }

}


$object = new MyClass();
$object->ID = 'foo'; //setID('foo') will be called

回答by Jaspreet Chahal

Mchiis right, but there is another way of doing it by using single function

Mchi是对的，但还有另一种方法可以通过使用单个函数来实现

    private $ID;

public function ID( $value = "" )

{

    if( empty( $value ) )

        return $this->ID;

    else

        $this->ID = $value;

}

But yeah this approach is pretty much inline with what you do in c#. but this is only an alternative

但是，是的，这种方法与您在 c# 中所做的非常一致。但这只是一个替代方案

Or try using php's __set and __get in your class more info here

或者尝试在您的课程中使用 php 的 __set 和 __get 更多信息

http://php.net/manual/en/language.oop5.overloading.php

http://php.net/manual/en/language.oop5.overloading.php

回答by Piotr Czy?

Thanks for your answers everyone. It helped me to create something like this:

谢谢大家的回答。它帮助我创造了这样的东西：

In my parent class:

在我的父类中：

public function __get($name){

    if (ObjectHelper::existsMethod($this,$name)){
        return $this->$name();
    }

    return null;
}

public function __set($name, $value){

    if (ObjectHelper::existsMethod($this,$name))
        $this->$name($value);
}

ObjectHelper::existsMethod is a method which just check if given protected method exists.

ObjectHelper::existsMethod 是一种只检查给定受保护方法是否存在的方法。

private $_propertyName = null;

protected function PropertyName($value = ""){

    if (empty($value)) // getter
    {
        if ($this-> _propertyName != null)
            return $this->_propertyName;
    }
    else // setter
    {
        $this-> _propertyName = $value;
    }

    return null;
}

So I can use something like this in any class:

所以我可以在任何课程中使用这样的东西：

$class = new Class();
$class->PropertyName = "test";
echo $class->PropertyName;

I was inspired by C# :)

我的灵感来自 C# :)

What do you think about this, guys?

小伙伴们，你们怎么看？

Here is my ObjectHelper if someone would like to use it:

如果有人想使用它，这是我的 ObjectHelper：

namespace Helpers;

use ReflectionMethod;

class ObjectHelper {

public static function existsMethod($obj, $methodName){

    $methods = self::getMethods($obj);

    $neededObject = array_filter(
        $methods,
        function ($e) use($methodName) {
            return $e->Name == $methodName;
         }
    );

    if (is_array($neededObject))
        return true;

    return false;
}

public static function getMethods($obj){

    $var = new \ReflectionClass($obj);

    return $var->getMethods(ReflectionMethod::IS_PROTECTED);
}
}

回答by user3397560

Another exampled using Variable function name

另一个使用变量函数名的例子

class MyClass {

  private $ID;
  protected $ID2;

  private function setID($ID) {
    $this->ID = $ID;
  }
  private function getID() {
    return $this->ID;
  }
  private function setID2($ID2) {
    $this->ID2 = $ID2;
  }

  private function getID2() {
    return $this->ID2;
  }
  public function __set($name,$value) {
    $functionname='set'.$name;
    return $this->$functionname($value);
  }
  public function __get($name) {
    $functionname='get'.$name;
    return $this->$functionname();
  }

}


$object = new MyClass();
$object->ID = 'foo'; //setID('foo') will be called
$object->ID2 = 'bar'; //setID2('bar') will be called

回答by user3397560

private $ID;

public function getsetID($value = NULL)
{
    if ($value === NULL) {
        return $this->ID;
    } else {
        $this->ID = $value;
    }
}

回答by rmblstrp

I know I am a bit late to the party on this question, but I had the same question/thought myself. As a C# developer who does PHP, when the job requires, I want to have a simple way to create properties just I would be able to in C#.

我知道我在这个问题上有点晚了，但我自己也有同样的问题/想法。作为一名从事 PHP 的 C# 开发人员，当工作需要时，我希望有一种简单的方法来创建属性，就像我能够在 C# 中那样。

I whipped up a first draft this afternoon which allows you to create the backing fields and specify their accessors or have pure accessors with no backing field. I will update my answer as the code evolves and provide a link when I get it to the state where it can be imported as a composer package.

我今天下午起草了一份初稿，它允许您创建支持字段并指定它们的访问器或拥有没有支持字段的纯访问器。随着代码的发展，我将更新我的答案，并在我将其变为可以作为 Composer 包导入的状态时提供链接。

For simplicity, I created the functionality as a PHP trait so you can drop it in to any class you want instead of having to extend a base class. Eventually I hope to extend this functionality to discern between external public calls to the properties and protected/private calls.

为简单起见，我将该功能创建为 PHP 特性，因此您可以将其放入任何您想要的类中，而不必扩展基类。最终，我希望扩展此功能以区分对属性的外部公共调用和受保护/私有调用。

Here is the code for the trait itself:

这是特征本身的代码：

trait PropertyAccessorTrait
{
    private static $__propertyAccessors = [];

    /* @property string $__propertyPrefix */

    public function __get($name)
    {
        $this->__populatePropertyAcessors($name);

        return $this->__performGet($name);
    }

    public function __set($name, $value)
    {
        $this->__populatePropertyAcessors($name);

        $this->__performSet($name, $value);
    }

    public function __isset($name)
    {
        // TODO: Implement __isset() method.
    }

    public function __unset($name)
    {
        // TODO: Implement __unset() method.
    }

    protected function __getBackingFieldName($name)
    {
        if (property_exists(self::class, '__propertyPrefix')) {
            $prefix = $this->__propertyPrefix;
        } else {
            $prefix = '';
        }

        return $prefix . $name;
    }

    protected function __canget($name)
    {
        $accessors = $this->__getPropertyAccessors($name);

        return $accessors !== null && isset($accessors['get']);
    }

    protected function __canset($name)
    {
        $accessors = $this->__getPropertyAccessors($name);

        return $accessors !== null && isset($accessors['set']);
    }

    protected function __performGet($name)
    {
        if (!$this->__canget($name)) {
            throw new \Exception('Getter not allowed for property: ' . $name);
        }

        $accessors = $this->__getPropertyAccessors($name)['get'];

        /* @var \ReflectionMethod $method */
        $method = $accessors['method'];

        if (!empty($method)) {
            return $method->invoke($this);
        }

        return $this->{$this->__getBackingFieldName($name)};
    }

    protected function __performSet($name, $value)
    {
        if (!$this->__canset($name)) {
            throw new \Exception('Setter not allowed for property: ' . $name);
        }

        $accessors = $this->__getPropertyAccessors($name)['set'];

        /* @var \ReflectionMethod $method */
        $method = $accessors['method'];

        if (!empty($method)) {
            return $method->invoke($this, $value);
        }

        $this->{$this->__getBackingFieldName($name)} = $value;
    }

    protected function __getPropertyAccessors($name)
    {
        return isset(self::$__propertyAccessors[$name])
            ? self::$__propertyAccessors[$name]
            : null
            ;
    }

    protected function __getAccessorsFromDocBlock($docblock)
    {
        $accessors = [];

        if (!empty(trim($docblock))) {
            $doclines = null;

            if (!empty($docblock)) {
                $doclines = explode("\n", $docblock);
            }

            if (!empty($doclines)) {
                foreach ($doclines as $line) {
                    if (preg_match('/@(get|set)\s+(public|private|protected)/', $line, $matches)) {
                        $accessors[$matches[1]]['visibility'] = $matches[2];
                    }
                }
            }
        }

        return $accessors;
    }

    protected function __populatePropertyAcessors($name)
    {
        if ($this->__getPropertyAccessors($name) !== null) return;

        try {
            $property = new \ReflectionProperty(self::class, $this->__getBackingFieldName($name));
        } catch (\ReflectionException $ex) {
            $property = null;
        }

        $accessors = [];

        if ($property != null) {
            $accessors = $this->__getAccessorsFromDocBlock($property->getDocComment());
        }

        try {
            $methodName = 'get' . ucfirst($name);
            $method = new \ReflectionMethod(self::class, $methodName);
            $method->setAccessible(true);
            $accessors = array_merge($accessors, $this->__getAccessorsFromDocBlock($method->getDocComment()));
        } catch (\ReflectionException $ex) {
            $method = null;
        }


        if ($method !== null || isset($accessors['get'])) {
            $accessors['get']['method'] = $method;
        }

        try {
            $methodName = 'set' . ucfirst($name);
            $method = new \ReflectionMethod(self::class, $methodName);
            $method->setAccessible(true);
            $accessors = array_merge($accessors, $this->__getAccessorsFromDocBlock($method->getDocComment()));
        } catch (\ReflectionException $ex) {
            $method = null;
        }

        if ($method !== null || isset($accessors['set'])) {
            $accessors['set']['method'] = $method;
        }

        self::$__propertyAccessors[$name] = $accessors;
    }
}

Here is a quick unit test I created using the Codeception format:

这是我使用 Codeception 格式创建的快速单元测试：

<?php

class PropertyAssesorTraitTestClass
{
    use PropertyAccessorTrait;

    private $__propertyPrefix = '_';

    /**
     * @get public
     * @set public
     */
    private $_integer = 1;

    /**
     * @get public
     */
    private $_getonly = 100;

    /**
     * @set public
     */
    private $_setonly;

    private $_customDoubler;

    private function getCustomDoubler()
    {
        return $this->_customDoubler * 2;
    }

    private function setCustomDoubler($value)
    {
        $this->_customDoubler = $value * 2;
    }

    public $publicField = 1234;

    /**
     * @return int
     * @get public
     */
    private function getPureAccessor()
    {
        return $this->publicField;
    }

    /**
     * @param $value
     * @set public
     */
    private function setPureAccessor($value)
    {
        $this->publicField = $value;
    }

    private $_purePrivate = 256;
}

$I = new UnitTester($scenario);
$I->wantTo('Ensure properties are accessed correctly');

$instance = new PropertyAssesorTraitTestClass();
$I->assertSame(1, $instance->integer);

$instance->integer = 2;
$I->assertSame(2, $instance->integer);

$instance->integer = $instance->integer + 1;
$I->assertSame(3, $instance->integer);

$instance->integer++;
$I->assertSame(4, $instance->integer);

$I->assertSame(100, $instance->getonly);
$I->expectException('Exception', function () use ($instance) { $instance->getonly = 50; });

$instance->setonly = 50;
$I->expectException('Exception', function () use ($instance) { $a = $instance->setonly; });

$instance->customDoubler = 100;
$I->assertSame(400, $instance->customDoubler);

$I->assertSame(1234, $instance->publicField);
$instance->pureAccessor = 1000;
$I->assertSame(1000, $instance->publicField);
$instance->publicField = 1234;
$I->assertSame(1234, $instance->publicField);
$I->assertSame(1234, $instance->pureAccessor);

$I->expectException('Exception', function () use ($instance) { return $instance->purePrivate; });

回答by vagustolga

this is PHP ; you don't need get set

这是 PHP ；你不需要设置

class MyClass {
  public $ID;
}

$object = new MyClass();
$object->ID = 'foo';
echo $object->ID;

will work

将工作