If I have a CheckBoxList within a form, like this...

```
@using (Html.BeginForm("Save", "Product", FormMethod.Post))
{
    ...

    @Html.CheckBoxList("Categories", Model.AllCategories);

    ...
}

```

... how can I get a list of selected values (checked values) in my controller action?

For example, if the check box list has items with values of:

> 
> Cat. 1
> 
> 
> Cat. 2
> 
> 
> Cat. 3
> 
> 
> Cat. 4
> 
> 
> 

...and `Cat. 2` and `Cat. 3` are selected, how can I get an array containing those values?