Cannot set Price List when Previewing Form

I came across a quirk of the Preview functionality of the CRM 4.0 Form Editor. When previewing an entity with a relationship to the price list - e.g. opportunity, quote - the Price List lookup doesn't display any price lists, so you can't set one. As far as I can tell this is due to the multi-currency functionality - the lookup normally filters by currency, but this logic is missing from the preview. Manually setting a currency in the preview form doesn't help.

This caused me an issue once when testing client script, but there's a fairly simple way around it - you can still set the price list code. This is something I commonly do if the customer has just the one price list. Here is some sample code I use in the form load event:

if (crmForm.FormType == 1)
{
var o = new Object();
o.id = '{A0E0F731-E96C-DD11-AABD-0003FF74F5B7}'; /* Change this Guid */
o.typename = 'pricelevel';
o.name = 'Standard Price List';
var a = new Array();
a[0] = o;
crmForm.all.pricelevelid.DataValue = a;
}

Note that this is only appropriate in a single-currency scenario. If you have multiple currencies, you'd be better off putting the code in the change event for the currency field, and picking an appropriate price list for the currency.