Keys can be one of three types, selected by choosing the appropriate constructor:
Descriptor type
Text type
Numeric type
The key is defined to be a descriptor, i.e. an object derived
from TDesC
. In practice, a descriptor key within an array element
is one of the types: TPtrC
, TPtr
,
TBufC
or TBuf
(but not an
HBufC
).
For a Unicode build, they are
defined as TDesc16
, TPtrC16
, TPtr16
,
TBufC16
and TBuf16
respectively, while for a non-Unicode build, they are
defined as TDesc8
TPtrC8
, TPtr8
, TBufC8
and
TBuf8
respectively.
The key is defined to be of type TText
. For a
Unicode build, TText
is defined as TText16
while
for a non-Unicode build, it is defined as TText8
.