I have the following javascript code

```
$(".order-event-btn").click(function(e) {
$.ajax({
url: "URL",
type: "POST",
data: {
    eventId: $(e.target).attr('data-event-id'),
},
success: function(data) {
    //Some code
},
error: function(data) {
    //Some code
},
});
});

```

I include this script using "BookAsset".

Here

```
url: "URL",

```

I need URL to the action "book-event" in the controller Book.

On the server, I can do this:

```
 Url::to('/book/book-event')

```

But how do I get URL on client side?

**There is an solution:** 

**1.** js file include via BookAsset.

**2.** in view file I register bundle: 

```
\frontend\assets\BookAsset::register($this);

```

**3.** in view file define a bookEventURL variable. Now it is available in the js-file. 

```
$this->registerJs('var bookEventURL = ' . Url::to('/book/book-event') . ';');

```

**But I do not like this solution.**
What will happen when I use this script in many views. I have to define a variable bookEventURL in each view?

**My Question**. Is it possible to bind js-variables to my BookAsset. When I register my BookAsset in the view, in page source code automatically insert next code:

```
<script>var bookEventURL = "http://example.com/book-event/";</script>

```