A switch/case statement in mIRC syntax would be like this (if it followed C):

Code:
switch ($time(HH:nn)) {
  case (10:00) {
    ; $time(HH:nn) is 10:00
    break
  }
  case (11:00) {
    ; $time(HH:nn) is 11:00
    break
  }
  default {
    ; $time(HH:nn) is neither of the above
  }
  ; Here is where the script will go to when mIRC hits a break statement. 
  ; Without the break statements mIRC would just fall through to the next case.
}