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

Concepts

Library Functions