学习php oop - 无法反转数组

Question

I'm learning PHP OOP and Im trying to understand why the following script doesn't work:

class ShowTimeline {
    var $conn;
    var $rev;

    function getTimeline ($conn) {
        return $this->conn;
    }

    function reverseTimeline () {
        $rev = array_reverse($this->conn, false);
        return $rev;
    }

    function display () {
        $this->reverseTimeline();
        print_r($this->rev);
    }
}
print '<hr />';
$connect = new showTimeline();
$connect->conn = array('one', 'two', 'three');
$connect->display();

When I change the script to:

//same stuff above
function display () {
            $this->reverseTimeline();
            print_r($this->conn); //changed from $this->rev
        }
//same stuff below

I get the print out:

Array ( [0] => one [1] => two [2] => three )

which is correct. Please help?

Answer 1

Access class' parameters with $this->.

function reverseTimeline () {
    $this->rev = array_reverse($this->conn, false);
    return $this->rev;
}

Using just $rev it is treated as a local variable.