What's the best way to limit the users choices on input?

[creolejazz]

I have a field into which I want my data entry people to be able to enter ONLY "B" or "G" (for boy or girl). They can leave it blank, but if anything at all is entered it must be either B or G. What's the best way to achieve that?

 

[rainman89]

create a combo box to do it?
or put something in the beforeupdate event of the box to check it... can be done either way really...

 

[boblarson]

I'd go with a combo or option group.

 

[rainman89]

I'd go with a combo or option group.

what options are those??
.do it right
.do it wrong and have your fingers broke?

 

[boblarson]

what options are those??
.do it right
.do it wrong and have your fingers broke?