When someone will click on a link such as Content/View/
you cannot hide id 45 or something else.
you can hide Ids by using SEO friendly Urls.
Like you can have Content/View/about-us where about-us is permalink to that page content in DB or in some array.
and in you action you can get id based on this permalink (This permalink should be created / generated when adding new content in backend admin panel)
second thought is to save these permalink in an array like $links = array('about-us'=>45)
and you can validate as
if(array_key_exists('about-us', $links)){
$id = $links['about-us'];
}
May be this can give you some idea.