std::islower
From cppreference.com
Defined in header
<cctype>
|
||
int islower( int ch );
|
||
Checks if the given character is classified as a lowercase character according to the current C locale. In the default "C" locale, islower
returns true only for the lowercase letters (abcdefghijklmnopqrstuvwxyz
).
If islower
returns true, it is guaranteed that iscntrl, isdigit, ispunct, and isspace return false for the same character in the same C locale.
The behavior is undefined if the value of ch
is not representable as unsigned char and is not equal to EOF.
Contents |
[edit] Parameters
ch | - | character to classify |
[edit] Return value
Non-zero value if the character is a lowercase letter, zero otherwise.
[edit] Example
Run this code
#include <iostream> #include <cctype> #include <clocale> int main() { unsigned char c = '\xe5'; // letter å in ISO-8859-1 std::cout << "islower(\'\\xe5\', default C locale) returned " << std::boolalpha << (bool)std::islower(c) << '\n'; std::setlocale(LC_ALL, "en_GB.iso88591"); std::cout << "islower(\'\\xe5\', ISO-8859-1 locale) returned " << std::boolalpha << (bool)std::islower(c) << '\n'; }
Output:
islower('\xe5', default C locale) returned false islower('\xe5', ISO-8859-1 locale) returned true
[edit] See also
checks if a character is classified as lowercase by a locale (function template) |
|
checks if a wide character is lowercase (function) |
|
C documentation for islower
|
ASCII values (hex) |
characters |
islower |
||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0 - 8 | 0x00-0x08
|
control codes (NUL , etc.)
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
9 | 0x09
|
tab (\t )
|
≠0
|
0
|
≠0
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
10 - 13 | 0x0A-0x0D
|
whitespaces (\n ,\v ,\f ,\r )
|
≠0
|
0
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
14 - 31 | 0x0E-0x1F
|
control codes |
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
32 | 0x20
|
space | 0
|
≠0
|
≠0
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
33 - 47 | 0x21-0x2F
|
!"#$%&'()*+,-./
|
0
|
≠0
|
0
|
0
|
≠0
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
48 - 57 | 0x30-0x39
|
0123456789
|
0
|
≠0
|
0
|
0
|
≠0
|
0
|
≠0
|
0
|
0
|
0
|
≠0
|
≠0
|
58 - 64 | 0x3a-0x40
|
:;<=>?@
|
0
|
≠0
|
0
|
0
|
≠0
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
65 - 70 | 0x41-0x46
|
ABCDEF
|
0
|
≠0
|
0
|
0
|
≠0
|
0
|
≠0
|
≠0
|
≠0
|
0
|
0
|
≠0
|
71 - 90 | 0x47-0x5A
|
GHIJKLMNOPQRSTUVWXYZ
|
0
|
≠0
|
0
|
0
|
≠0
|
0
|
≠0
|
≠0
|
≠0
|
0
|
0
|
0
|
91 - 96 | 0x5B-0x60
|
[\]^_`
|
0
|
≠0
|
0
|
0
|
≠0
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
97 -102 | 0x61-0x66
|
abcdef
|
0
|
≠0
|
0
|
0
|
≠0
|
0
|
≠0
|
≠0
|
0
|
≠0
|
0
|
≠0
|
103-122 | 0x67-0x7A
|
ghijklmnopqrstuvwxyz
|
0
|
≠0
|
0
|
0
|
≠0
|
0
|
≠0
|
≠0
|
0
|
≠0
|
0
|
0
|
123-126 | 0x7B-0x7E
|
{|}~
|
0
|
≠0
|
0
|
0
|
≠0
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
127 | 0x7F
|
backspace character (DEL )
|
≠0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|