PHP获取对象属性方法

今天查看源码，发现yii\base\Model中的attribute()方法是通过反射获取对象的public non-static属性。记得以前看到的代码都是用get_object_vars()这个函数获取的(返回由对象属性组成的关联数组)，昨天查看php文档，发现还可以用foreach遍历对象属性。于是写个例子练习下：

class TestClass{
    private $a;
    protected $b;
    public $c;
    public $d;
    public static $e;
    private function funcA() {
    }
    protected function funcB() {
    }
    public function funcC() {
    }

    public function getPropertyMethodOne(){
        echo "[get_object_vars]",PHP_EOL;
        $vars = get_object_vars($this);
        //获取对象属性列表数组，再遍历数组
        foreach ($vars as $k => $v){
            echo $k, ' => ', $v, PHP_EOL;
        }
    }
    public function getPropertyMethodTwo(){
        echo "[foreach object]",PHP_EOL;
        //foreach遍历对象属性
        foreach ($this as $k=>$v){
            echo $k, ' => ', $v, PHP_EOL;
        }
    }
    public function getPropertyMethodThree(){
        echo "[reflection]", PHP_EOL;
        $class = new \ReflectionClass($this);
        //反射获取类的public属性
        foreach ($class->getProperties(\ReflectionProperty::IS_PUBLIC) as $property){
            if(!$property->isStatic()){
                echo $property->getName(), ' => ' , $property->getValue($this), PHP_EOL;
            }
        }
    }
}

测试demo1:

$obj = new TestClass();
        echo "[get_object_vars]",PHP_EOL;
        $vars = get_object_vars($obj);
        foreach($vars as $k=>$v ){
            echo $k, ' => ', $v, PHP_EOL;
        }
        echo "[foreach object]", PHP_EOL;
        foreach ($obj as $k=>$v){
            echo $k ,' => ', $v, PHP_EOL;
        }
        echo "[reflection]", PHP_EOL;
        $class = new \ReflectionClass($obj);
        foreach ($class->getProperties(\ReflectionProperty::IS_PUBLIC) as $property){
            if(!$property->isStatic()){
                echo $property->getName(), ' => ' , $property->getValue($obj), PHP_EOL;
            }
        }

输出：

[get_object_vars]
c => 
d => 
[foreach object]
c => 
d => 
[reflection]
c => 
d =>  

可见，当这三种方法用在类的外部时，结果是一样的。get_object_vars()和foreach是获取到的是对象的public non-static属性，而通过反射的话则需要手动筛选出public non-static属性。
测试demo2:

        $obj = new TestClass();
        $obj->getPropertyMethodOne();
        $obj->getPropertyMethodTwo();
        $obj->getPropertyMethodThree();

输出：

[get_object_vars]
a => 
b => 
c => 
d => 
[foreach object]
a => 
b => 
c => 
d => 
[reflection]
c => 
d => 

可见，get_object_vars()和foreach用在类内部时，private、protected、public的实例属性都能获取到。反射就不用说了，通过手动筛选，各种类型的属性都能获取到。
类的知识点补充：

namespace App\Model;
class TestClass {
    private $a = '初始值a' ;
    protected $b;
    public $c;
    public $d;
    public static $e;

    public function getPropertyMethodThree(){
        $this->a = 'wudy.yu';
        $class = new \ReflectionClass($this);
        echo $class->getName() , PHP_EOL;  //App\Model\TestClass
        echo $class->name,PHP_EOL;  //App\Model\TestClass
        var_dump($class->getDefaultProperties()). PHP_EOL;  //获取所有属性的初始默认值(后面赋值的不算)
        echo $class->getEndLine(),PHP_EOL; //获取类的最后行的行数
    }
}

输出:

App\Model\TestClass
App\Model\TestClass
array(5) {
  ["e"]=>
  NULL
  ["a"]=>
  string(10) "初始值a"
  ["b"]=>
  NULL
  ["c"]=>
  NULL
  ["d"]=>
  NULL
}
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