PHP Navigation Bar with array

@$nav_normal = array(
    "Home" => $locationHome,
    "(Un)Subscribe" => $locationSubscribe,
    "About Us" => $locationAbout,
    "Login" => $locationLogin
    ); //this will be the list of the public visible nav bar links
@$nav_acp = array();


//$Nav_ID will be set for each page manually as E.G Home
if(in_array($Nav_ID,$nav_normal)){

//so if $Nav_ID equals in the nav_normal array then it uses the foreach loop I created...
//but how can I check if nav_id is in the list (home is in the list but the nav isn't showing...)