Checking variable for A-Z

[Kladkul]

Is there a quick and easy way to check a variable to be A-Z? I figure I have to do it character by character but past that I am unsure as character data types allow more then just A-Z.

 

[tamhas]

Is this testing or controlling input? Is it fixed length with no blanks allowed. If so, you should look at a format using A or ! depending on whether you want it upper case, but note that !!!!!! *must* get 6 characters.

How long are the strings? If they are long, then you might experiment with using a bunch of REPLACE statements to convert each letter to "" and then see if you have anything left at the end.

 

[DevTeam]

Did you try your idea of checking that each character is between "a" and "z" ? I seems to be correct, but it may not be the most efficient in response time...

FUNCTION is_A_Z RETURNS LOGICAL (INPUT VarCh AS CHAR) :
  DEF VAR tmp AS CHAR    NO-UNDO.
  DEF VAR cpt AS INTEGER NO-UNDO.

  DO cpt = 1 TO LENGTH(VarCh) :
    tmp = SUBSTRING(VarCh , cpt, 1).
    IF tmp < "a" OR tmp > "z"
    THEN RETURN NO.
  END.

  RETURN YES.
END FUNCTION.

 

[Kladkul]

Tamhas, this is for controlling input, and it is only a 2 character field. DevTeam, that method may work, I'll do some testing with it and see how long it takes to check, since it's only a 2 character field the response time shouldn't be to bad.

 

[TomBascom]

define variable c as character no-undo format "x(2)".

form c with frame a.

on "any-printable" anywhere do:
  if ( lastkey >= asc( "a" ) and lastkey <= asc( "z" ) ) or
     ( lastkey >= asc( "A" ) and lastkey <= asc( "Z" ) ) then
    return.
   else
    return no-apply.
end.

enable c with frame a.

wait-for "go" of frame a.

 

[tamhas]

If it is always two characters, i.e., one character or blank are not allowable, then the format characters will be the simplest solution. Otherwise, go with something like Tom's.

 

[Kladkul]

Thanks for the help!