关于zend framework1中url方法的问题

class Zend_View_Helper_Url extends Zend_View_Helper_Abstract {
    /**
     * Generates an url given the name of a route.
     *
     * @access public
     *
     * @param  array $urlOptions Options passed to the assemble method of the Route object.
     * @param  mixed $name The name of a Route to use. If null it will use the current Route
     * @param  bool $reset Whether or not to reset the route defaults with those provided
     * @return string Url for the link href attribute.
     */
    public function url(array $urlOptions = array(), $name = null, $reset = false, $encode = true)
    {
        $router = Zend_Controller_Front::getInstance()->getRouter();
        return $router->assemble($urlOptions, $name, $reset, $encode);
    } }

以上代码来自zend/view/helper/url.php。

问题:

在注释中，它是生成一个url给定路由的名称，在zend框架中的路由是什么?以下代码来自:index.phtml

<a href="<?php echo $this->url(array('controller'=>'index',
'action'=>'edit', 'id'=>$album->id));?>">Edit</a>

那么你能解释一下url()方法在这里是如何起作用的吗?