std::ctype<CharT>::toupper, std::ctype<CharT>::do_toupper

< cpp‎ | locale‎ | ctype
Localizations library
Locales and facets
Facet category base classes
ctype facets
numeric facets
collate facets
time facets
monetary facets
messages facets
Character classification and conversion
Character classification
Code conversion facets
C locale
Text encoding identifications
Defined in header <locale>
CharT toupper( CharT c ) const;
const CharT* toupper( CharT* beg, const CharT* end ) const;
virtual CharT do_toupper( CharT c ) const;
virtual const CharT* do_toupper( CharT* beg, const CharT* end ) const;
1,2) Public member function, calls the protected virtual member function do_toupper of the most derived class.
3) Converts the character c to upper case if an upper case form is defined by this locale.
4) For every character in the character array [begend), for which an upper case form exists, replaces the character with that upper case form.


[edit] Parameters

c - character to convert
beg - pointer to the first character in an array of characters to convert
end - one past the end pointer for the array of characters to convert

[edit] Return value

1,3) Upper case character or c if no upper case form is listed by this locale.
2,4) end

[edit] Notes

Only 1:1 character mapping can be performed by this function, e.g. the uppercase form of 'ß' is the two-character string "SS" (with some exceptions - see «Capital ẞ»), which cannot be obtained by do_toupper.

[edit] Example

#include <iostream>
#include <locale>
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';
        std::wcout << '\'' << c << "' has no upper case form\n";
int main()
    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'δ');
    try_upper(f, L'ö');
    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";


In US English UTF-8 locale:
Upper case form of 's' is S
Upper case form of 'ſ' is S
Upper case form of 'δ' is Δ
Upper case form of 'ö' is Ö
'ß' has no upper case form
Uppercase form of the string 'Hello, World!' is 'HELLO, WORLD!'

[edit] See also

invokes do_tolower
(public member function) [edit]
converts a character to uppercase
(function) [edit]
converts a wide character to uppercase
(function) [edit]