Conditional Tag for Wishlist membership. If the user is added to two levels show particular content

If you’re running the latest version of WishList Member, it now has built-in API functions for stuff like this. Using those, you’d do this:

wp_get_current_user();

$gold_sku = 123456789;
$silver_sku = 987654321;
$user_id = $user->ID;

if ( wlmapi_is_user_a_member($gold_sku, $user_id) ) {
     //Do gold stuff here
} elseif ( wlmapi_is_user_a_member($silver_sku, $user_id) ) {
     //Do silver stuff here
}

If want to check that they belong to BOTH levels, do this:

if ( wlmapi_is_user_a_member($gold_sku, $user_id) && wlmapi_is_user_a_member($silver_sku, $user_id) ) {
     //Do gold AND silver stuff here
}

If you want to check that they belong to EITHER level, do this:

if ( wlmapi_is_user_a_member($gold_sku, $user_id) || wlmapi_is_user_a_member($silver_sku, $user_id) ) {
     //Do gold AND silver stuff here
}

You can check the Codex for this function here:

http://codex.wishlistproducts.com/function-reference-wlmapi_is_user_a_member/