std::islower

 

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字符串库

null结尾的字符串 Original: Null-terminated strings The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

字节的字符串

多字节字符串

宽字符串

类 Original: Classes The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

basic_string

char_traits

 

NULL结尾的字节串

功能 Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
字符操作 Original: Character manipulation The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
isalnum isalpha islower isupper isdigit isxdigit isblank （C++11）	iscntrl isgraph isspace isprint ispunct tolower toupper
转换为数字格式 Original: Conversions to numeric formats The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
atof atoi atol atoll strtol strtoll	strtoul strtoull strtof strtod strtold
字符串操作 Original: String manipulation The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
strcpy
strncpy
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strxfrm
字符串检查 Original: String examination The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
strlen strcmp strncmp strcoll strchr strrchr	strspn strcspn strpbrk strstr strtok
内存操作 Original: Memory manipulation The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
memchr
memcmp
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memcpy
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杂项 Original: Miscellaneous The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
strerror

 

Defined in header <cctype>
int islower( int ch );

。检查是否给定的字符被归类为小写字符，根据当前的C语言环境。在默认的“C”语言环境，islower返回true，只为小写字母（abcdefghijklmnopqrstuvwxyz）.

Original:

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).

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。如果islower回报true，这是保证iscntrl，isdigit，ispunct，和相同的字符在同一个C语言环境下的isspace回报false.

Original:

If islower returns true, it is guaranteed that iscntrl, isdigit, ispunct, and isspace return false for the same character in the same C locale.

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。参数。

ch

-

。字符。 Original: character The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

===。 返回值。===

。非零值（true）如果字符是小写字母，0（false），否则.

Original:

Non-zero value (true) if the character is a lowercase letter, 0 (false) otherwise.

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。为例。

#include <iostream>
#include <cctype>
#include <clocale>
 
int main()
{
    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

。另请参阅。

islower(std::locale)	检查，如果一个字符被归类为小写的语言环境 Original: checks if a character is classified as lowercase by a locale The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （函数模板）
iswlower	检查是否使用了一个宽字符是小写的 Original: checks if a wide character is lowercase The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （函数）
C documentation for islower

ASCII values (hex)		characters	iscntrl iswcntrl	isprint iswprint	isspace iswspace	isblank iswblank	isgraph iswgraph	ispunct iswpunct	isalnum iswalnum	isalpha iswalpha	isupper iswupper	islower iswlower	isdigit iswdigit	isxdigit iswxdigit
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