Our client would like to sort the search results based on a doctype. I found an article on this for Umbraco 7 using the below

public void DocumentWriting(object sender, DocumentWritingEventArgs e)
{
    // boost doctype on indexing
    if (e.Fields["nodeTypeAlias"] == "YourDocTypeAlias")
    {
        e.Document.SetBoost(2);
    }
}

Is there a way to do this in Umbraco 8 or another way we could achieve this?