std::ctype<CharT>::toupper, std::ctype<CharT>::do_toupper
来自cppreference.com
| 在标头 <locale> 定义
|
||
| public: CharT toupper( CharT c ) const; |
(1) | |
| public: const CharT* toupper( CharT* beg, const CharT* end ) const; |
(2) | |
| protected: virtual CharT do_toupper( CharT c ) const; |
(3) | |
| protected: virtual const CharT* do_toupper( CharT* beg, const CharT* end ) const; |
(4) | |
1,2) 公开成员函数，调用最终导出类上的受保护虚成员函数
do_toupper 。3) 若此 locale 定义
c 的大写形式，则转换它为大写形式。4) 对字符数组
[beg, end) 中每个存在大写形式的字符，以其大写形式替换该字符。参数
| c | - | 要转换的字符 |
| beg | - | 指向要转换的数组中首字符的指针 |
| end | - | 指向要转换的数组尾后一位置的指针 |
返回值
1,3) 大写字符，或若无列于此 loacale 的大写形式则为
c 。2,4)
end 。注意
此函数只能进行 1:1 字符映射，例如 'ß' 的大写形式（有一些例外）是双字符字符串 "SS" ，它无法以 do_toupper 获得。
示例
运行此代码
#include <locale> #include <iostream> void try_upper(const std::ctype<wchar_t>& f, wchar_t c) { wchar_t up = f.toupper(c); if (up != c) { std::wcout << "Upper case form of \'" << c << "' is " << up << '\n'; } else { std::wcout << '\'' << c << "' has no upper case form\n"; } } int main() { std::locale::global(std::locale("en_US.utf8")); std::wcout.imbue(std::locale()); std::wcout << "In US English UTF-8 locale:\n"; auto& f = std::use_facet<std::ctype<wchar_t>>(std::locale()); try_upper(f, L's'); try_upper(f, L'ſ'); try_upper(f, L'ß'); std::wstring str = L"Hello, World!"; std::wcout << "Uppercase form of the string '" << str << "' is "; f.toupper(&str[0], &str[0] + str.size()); std::wcout << "'" << str << "'\n"; }
输出：
In US English UTF-8 locale: Upper case form of 's' is S Upper case form of 'ſ' is S 'ß' has no upper case form Uppercase form of the string 'Hello, World!' is 'HELLO, WORLD!'
参阅
调用 do_tolower (公开成员函数) | |
| 转换字符为大写 (函数) | |
| 转换宽字符为大写 (函数) |