Can spouse go for H4 visa stamping when primary H1B stamped visa is expired and have a H1B extension approved?

Am in USA in H1B with stamped visa expired, i have applied for the extension and now i have received the approval notice (i797) which is valid till next year. In this case, can my wife appear for visa stamping from India for H4 Visa, if so, what would be the validity on her Visa, will it be till my i797 extension validity date

if so, what would be the validity on her Visa, will it be till my i797 extension validity date
Ans: Yes