Character Classification (Windows CE 5.0)
Developing an Application > Microsoft C Run-time Library for Windows CE > Run-time Routines by Category
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;
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
Microsoft C Run-time Library for Windows CE | Run-time Library Reference
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