Syntax to add variable to snippet call

Probably pretty simple, I’m trying to show a chunk on each page which lists pages below this level. Therefore, I’m using DropMenu starting with the current docID as startDoc. However, I can’t get this to work.

[[DropMenu? &startDoc=[*id*] ]] doesn’t work.

Edit:

[!DropMenu? &startDoc=[*id*] !] does work! Tricked by cached snippets!

Next step would be toonly show this menu if (and only if) there is something to show. How would I accomplish this?

Thank you.

Nothing will be returned if there aren’t any documents to list.

Agreed, but I’m calling the DropMenu snippet in a chunk that has style in it, f.e.

<div class="leftbox">
[!DropMenu? &startDoc=[*id*]!]
</div>

The <div> (in this case with background image) still shows up. Are there any conditional statements I could use?