H4 Visa with only petition not visa stamping(Urgent)

Hi,

I came to US on H1 with Company A, I worked for a month with one pay slip and done H1 Transfer with Company B, I got my approved I797, can my wife attend Visa Interview with approved I797 as I dont have visa stamped with Company B. Please let me know all documents to carry, do I need to give my Old petition from Company A too.

Please its urgent, experts kindly reply.

Experts please explain on the sameā€¦

Please experts answer my query.