How to use Url::remember in yii2 - yii2

Question

I want to create a link on my error page to take user back to the previous link.
Suppose the current URL is http://example.com/site/product, and a user try to view
http://example.com/site/product?id=100 and a product with id =100 does not exit, the system should throw 404 error to the error page, now if i want to create a link to take the user back to http://example.com/site/product the previous URl how do I make this work. i can make this work by hardcoding this in my error views file, but i want it dynamically as i have many controller an action using the same view file.
I try this in my site conteoller
controller/site
public function actions()
{
$url = Url::remember();
return [
'error' => [
'class' => 'yii\web\ErrorAction',
],
$this->render('error',['url'=>$url]),
];
}
and try to get the value the in error view file like this
/views/site/error.php
<p>
<?= Html::a('go back', [$url)?>
</p>
but it has no vaule..
please any good idea on how to make this work, am also open to new solution

Answer 1

this is form Yii2 Guide http://www.yiiframework.com/doc-2.0/guide-helper-url.html#remember-urls
There are cases when you need to remember URL and afterwards use it
during processing of the one of sequential requests. It can be
achieved in the following way:
// Remember current URL Url::remember();
// Remember URL specified. See Url::to() for argument format.
Url::remember(['product/view', 'id' => 42]);
// Remember URL specified with a name given
Url::remember(['product/view', 'id' => 42], 'product');
In the next
request we can get URL remembered in the following way:
$url = Url::previous();
// or
$productUrl = Url::previous('product');