Conditional formatting based on other table field (1 Viewer)

i mean i have an form which comes from
table-A
Form name formAAone
inside have an field txtbox-AAA
but
i need make an conticional fromatting in txtboxAAA
but this have to be compare to table-B
table-B is an list of number
then if the number is there
imean they are equal to one of teh list number
give an conditional formating to txtbox-AAA

please any idea ?
full appreciated you help !

this sounds like you want a query to compare tbl A to tbl B.

thanks Ranman256 for you time!
still dont' get it !