VB Form - Default Values

Once again I am trying to do something simple but useful with a VB Form and
getting stuck in the attempt. I would like a couple fields on a form for
Subcontractor Shipment Detail (SubShipD) to default to the value "1" but
only if no other value has previously been entered.

set SubShipD.number-field_2.scrvalue = 1
works fine unless the user overrides with a 2 and the VB form is later
re-entered (activated) in which case the 2 gets set to 1. I would like to
only set to 1 if the current value is zero.

Is there a way to test (do something like an IF) and say
IF SubShipD.number-field_2.scrvalue = 0 then set
SubShipD.number-field_2.scrvalue = 1 ?

Or do I have to run an external VB form program and if so where would I find
a list of commands (like an IF) for such programs?

Or perhaps I'm barking up the wrong tree and there is an easier way to set
an initial value for a form field?

-Todd Caughey
Harvey Vogel Mfg. Co.

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