if / vlookup vba userform

[p4nny]

Hi,

I would like to convert the following formula into VBA:

IF(AND(textbox1)<>"",vlookup(textbox1,Case_ID,1,0)=true), textbox3 = "no"

Textbox1 is on a userform
Case_ID is named range on a sheet called EDD_DB


If false then "yes"

Hope this makes sense