Character Testing

ANSI 4.3.1 The sets of characters tested for by the isalnum, isalpha, iscntrl, islower, isprint, and isupper functions

The following list describes these functions as they are implemented by the Microsoft C compiler.

Function	Tests For
isalnum	Characters 0 - 9, A-Z, a-z ASCII 48-57, 65-90, 97-122
isalpha	Characters A-Z, a-z ASCII 65-90, 97-122
iscntrl	ASCII 0 -31, 127
islower	Characters a-z ASCII 97-122
isprint	Characters A-Z, a-z, 0 - 9, punctuation, space ASCII 32-126
isupper	Characters A-Z ASCII 65-90

See also

Library Functions