CASE-SENSITIVE 字串

除非另有說明，否則 Progress ABL 中的所有字串都區分大小寫。

此示例將顯示一個訊息框，指出字串相同。

DEFINE VARIABLE str1 AS CHARACTER   NO-UNDO.
DEFINE VARIABLE str2 AS CHARACTER   NO-UNDO.

str1 = "abc".
str2 = "ABC".

IF str1 = str2 THEN 
    MESSAGE "The strings are identical" VIEW-AS ALERT-BOX.

要宣告字串區分大小寫，只需新增屬性 CASE-SENSITIVE 即可

DEFINE VARIABLE str1 AS CHARACTER   NO-UNDO CASE-SENSITIVE.
DEFINE VARIABLE str2 AS CHARACTER   NO-UNDO.

str1 = "abc".
str2 = "ABC".

IF str1 = str2 THEN 
    MESSAGE "The strings are identical" VIEW-AS ALERT-BOX.
ELSE 
    MESSAGE "There's a difference" VIEW-AS ALERT-BOX.

（在這種情況下，其中一個字串就足夠了）。