Catalog Client Script: how to determine if loaded in Service Portal or Platform UI?

Basic principle is to use the URL via top.location which will be different in service portal:

function onLoad() {

    //shared functions for form load

    var urlString=top.location.toString();

    var bPortal=false; //--loaded from Service Portal?

    if(urlString.indexOf('rp?id=sc_cat_item&sys_id=')>-1){

        bPortal=true;

    }

   

    //--set hidden field--store sys id for ref qualifiers (referenced in script include MAB_refqual_functions)

    //--Cat item id:

    var itemID='';

    try{

        if (bPortal){

            itemID= g_form.getSysId(); //--service portal friendly

        }else{

            //--standard servicenow form

            itemID= gel('sysparm_id').value;

        }

    }catch (ex){

         //--

        alert('An error has occurred in the form load ' + ex.toString());

    }

    g_form.setValue('hidden_catitem_sysid',itemID );

    //alert(g_form.getValue('hidden_catitem_sysid'));

}