select case

Function myFun(num)

 Select Case num
   Case "Cash"
    msgbox "You are going to pay cash"
   Case "Visa"
    msgbox "You are going to pay with visa"
   Case "Amex"
    msgbox "You are going to pay with American Express"
   Case Else
    msgbox "Unknown method of payment"
 End select
End Function

Call myFun("Cash")