Character Testing
Visual Studio 2015
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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 |
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