[Zope] button instead of textlink and checking selection

Hi all, 1) Instead of using the text Next I want to use a button (form) ? How can I establish this ? <dtml-if next-sequence> <a href="<dtml-var URL><dtml-var sequence-query>query_start=<dtml-var next-sequence-start-number>"><br>Next<dtml-var next-sequence-size></a> </dtml-if next-sequence> 2) How can I check if REQUEST[''ids] is not empty when using <dtml-call "manage_delObjects(REQUEST['ids'])"> ? Thanks in advance. Michael