function item_xml_query_category_get(progress_em,form_id)
{var query_extra='';var catid=0;var tier=0;var form_id_full='omchat_'+form_id;while((select_em=document.getElementById(form_id_full+'_category_select_'+(tier++)))!=null)
{if(select_em.selectedIndex>0)catid=select_em.options[select_em.selectedIndex].value;else if(catid==0)
{if(progress_em!=null)progress_em.innerHTML='Please select a category.';return'';}}
if(catid>0)
{query_extra+='&catid='+catid;}
return query_extra;}