VS_ValKeys()         VALID clause to test if key is in a list

Description:

  VS_ValKeys() allows the programmer to see if key is in a list of valid
  keys.

Syntax:     

  l_Valid = VS_ValKeys( c_Key, c_KeyList, [@l_EatKeys] )

Pass:       

  c_Key is a character expression containing the key to search for.

  c_KeyList is a character expression containing the list of valid
  keys.

  l_Eating is an optional logical expression that can be used in
  place of VS_EatKeys()

Return:     

  l_Valid is a logical expression that will be set to .T. if
  c_Key is found to be in c_KeyList, otherwise it will be .F.

Notes:      


Example:    

  c_Key = " "
  @ 5,5 SAY "Type A, B, C or D: " GET c_Key VALID
  VS_ValKeys(c_Key,"ABCD")
  READ

Usage: