Character Classification (Windows Embedded CE 6.0)
1/5/2010
Character classification routines test a specified single-byte character or wide character for satisfaction of a condition. Generally these routines execute faster than tests you might write.
For example, the following code executes slower than a call to isalpha(c):
if ((c >= 'A') && (c <= 'Z')) || ((c >= 'a') && (c <= 'z'))
return TRUE;
For detailed reference information about the CRT functions, see Alphabetical Function Reference (CRT).
The following table shows the conditions tested by character classification routines.
| Routine | Character Test Condition |
|---|---|
__isascii, iswascii |
Determines if character is ASCII. |
_isctype, iswctype |
Determines if character is a property specified by parameter. |
isalnum, iswalnum |
Determines if character is alphanumeric. |
isalpha, iswalpha |
Determines if character is alphabetic. |
iscntrl, iswcntrl |
Determines if character is a control. |
isdigit, iswdigit |
Determines if character is a decimal digit |
isgraph, iswgraph |
Determines if character is printable, other than space. |
islower, iswlower |
Determines if character is lowercase. |
isprint, iswprint |
Determines if character is printable. |
ispunct, iswpunct |
Determines if character is punctuation. |
isspace, iswspace |
Determines if character is white-space. |
isupper, iswupper |
Determines if character is uppercase. |
isxdigit, iswxdigit |
Determines if character is a hexadecimal digit. |
See Also
Concepts
Other Resources
C/C++ Libraries for Windows Embedded CE
What's New in the C Run-Time Library