function template
<locale>

std::tolower

template <class charT>
  charT tolower (charT c, const locale& loc);
Convert uppercase letter to lowercase using locale
Converts parameter c to its lowercase equivalent if c is an uppercase letter and has a lowercase equivalent, as determined by the ctype facet of locale loc. If no such conversion is possible, the value returned is c unchanged.

This function returns the same as if ctype::tolower is called as:

 
 
use_facet < ctype<charT> > (loc).tolower (c)


This function template overloads the C function tolower (defined in <cctype>).

Parameters

c
Character to be converted.
loc
Locale to be used. It shall have a ctype facet.

The template argument charT is the character type.

Return Value

The lowercase equivalent to c, if any. Or c unchanged otherwise.

Example

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// tolower example (C++)
#include <iostream>       // std::cout
#include <string>         // std::string
#include <locale>         // std::locale, std::tolower

int main ()
{
  std::locale loc;
  std::string str="Test String.\n";
  for (std::string::size_type i=0; i<str.length(); ++i)
    std::cout << std::tolower(str[i],loc);
  return 0;
}


Output:

test string.

Data races

Both loc and its ctype facet are accessed.

Exception safety

Strong guarantee: if an exception is thrown, there are no effects.

See also

ctype
Character type facet (class template )
tolower (cctype)
Convert uppercase letter to lowercase (function )
toupper
Convert lowercase letter to uppercase using locale (function template )
isupper
Check if character is an uppercase letter using locale (function template )
islower
Check if character is a lowercase letter using locale (function template )
isalpha
Check if character is alphabetic using locale (function template )

C++