轉換大寫和小寫

如前所述，字串通常不區分大小寫，但僅考慮字串的比較。內建函式可以更換外殼。

CAPS（字串）

使字串大寫

LC（字串）

使字串小寫

DEFINE VARIABLE c AS CHARACTER   NO-UNDO.
DEFINE VARIABLE d AS CHARACTER   NO-UNDO.

c = "Hello".
d = "World".

DISPLAY CAPS(c) LC(d). // HELLO world

記住字串通常不區分大小寫

DEFINE VARIABLE c AS CHARACTER   NO-UNDO.
DEFINE VARIABLE d AS CHARACTER   NO-UNDO.

c = "hello".
d = "hello".

DISPLAY CAPS(c) = LC(d). // yes

除非特定為 CASE-SENSITIVE

DEFINE VARIABLE c AS CHARACTER   NO-UNDO CASE-SENSITIVE.
DEFINE VARIABLE d AS CHARACTER   NO-UNDO.

c = "hello".
d = "hello".

DISPLAY CAPS(c) = LC(d). // no