foreach遍历对象的属性

<?php
class  MyClass
{
    public  $var1  =  'value 1' ;
    public  $var2  =  'value 2' ;
    public  $var3  =  'value 3' ;

    protected  $protected  =  'protected var' ;
    private    $private    =  'private var' ;

    function  iterateVisible ()
    {
        foreach( $this  as  $key  =>  $value )
        {
            print  " $key  >>>  $value \n" ;
        }
    }
}

$class  = new  MyClass ();

foreach( $class  as  $key  =>  $value ) {
    print  " $key  =>  $value \n" ;
}
echo  "\n" ;

$class -> iterateVisible ();

?>