std::to_wstring

 

C++

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Symbols index

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basic_string

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std::basic_string

Member functions basic_string::basic_string basic_string::~basic_string basic_string::operator= basic_string::assign basic_string::assign_range (C++23) basic_string::get_allocator Element access basic_string::at basic_string::operator[] basic_string::front (DR*) basic_string::back (DR*) basic_string::data basic_string::c_str basic_string::operator  basic_string_view (C++17) Iterators basic_string::beginbasic_string::cbegin (DR*) basic_string::endbasic_string::cend (DR*) basic_string::rbeginbasic_string::crbegin (DR*) basic_string::rendbasic_string::crend (DR*) Capacity basic_string::empty basic_string::sizebasic_string::length basic_string::max_size basic_string::reserve basic_string::capacity basic_string::shrink_to_fit (DR*) Operations basic_string::clear basic_string::insert basic_string::insert_range (C++23) basic_string::erase basic_string::push_back basic_string::pop_back (DR*) basic_string::append basic_string::append_range (C++23) basic_string::operator+= basic_string::compare basic_string::replace basic_string::replace_with_range (C++23) basic_string::substr basic_string::copy basic_string::resize basic_string::resize_and_overwrite (C++23)   basic_string::swap

Search basic_string::starts_with (C++20) basic_string::ends_with (C++20) basic_string::contains (C++23) basic_string::find basic_string::rfind basic_string::find_first_of basic_string::find_first_not_of basic_string::find_last_of basic_string::find_last_not_of Constants basic_string::npos Deduction guides (C++17) Non-member functions operator+ swap(std::basic_string) operator""s (C++14) erase(std::basic_string)erase_if(std::basic_string) (C++20)(C++20) I/O operator<<operator>> getline Comparison operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20) Numeric conversion stoistolstoll (C++11)(C++11)(C++11) stoulstoull (C++11)(C++11) stofstodstold (C++11)(C++11)(C++11) to_string (C++11) to_wstring (C++11) Helper classes hash<std::string>hash<std::wstring>hash<std::u32string>hash<std::u16string>hash<std::u8string> (C++11)  (C++11)(C++11)(C++11)(C++20) hash<std::pmr::string>hash<std::pmr::wstring>hash<std::pmr::u32string>hash<std::pmr::u16string>hash<std::pmr::u8string> (C++17)(C++17)(C++17)(C++17)(C++20)

 

Defined in header <string>
std::wstring to_wstring( int value );	(1)	(since C++11)
std::wstring to_wstring( long value );	(2)	(since C++11)
std::wstring to_wstring( long long value );	(3)	(since C++11)
std::wstring to_wstring( unsigned value );	(4)	(since C++11)
std::wstring to_wstring( unsigned long value );	(5)	(since C++11)
std::wstring to_wstring( unsigned long long value );	(6)	(since C++11)
std::wstring to_wstring( float value );	(7)	(since C++11)
std::wstring to_wstring( double value );	(8)	(since C++11)
std::wstring to_wstring( long double value );	(9)	(since C++11)

Converts a numeric value to std::wstring.

Let buf be an internal to the conversion functions buffer, sufficiently large to contain the result of conversion. 1) Converts a signed decimal integer to a wide string as if by std::swprintf(buf, sz, L"%d", value). 2) Converts a signed decimal integer to a wide string as if by std::swprintf(buf, sz, L"%ld", value). 3) Converts a signed decimal integer to a wide string as if by std::swprintf(buf, sz, L"%lld", value). 4) Converts an unsigned decimal integer to a wide string as if by std::swprintf(buf, sz, L"%u", value). 5) Converts an unsigned decimal integer to a wide string as if by std::swprintf(buf, sz, L"%lu", value). 6) Converts an unsigned decimal integer to a wide string as if by std::swprintf(buf, sz, L"%llu", value). 7,8) Converts a floating point value to a wide string as if by std::swprintf(buf, sz, L"%f", value). 9) Converts a floating point value to a wide string as if by std::swprintf(buf, sz, L"%Lf", value).

(until C++26)

1-9) Converts a numeric value to a wide string as if by std::format(L"{}", value).

(since C++26)

Parameters

value

-

a numeric value to convert

Return value

A wide string holding the converted value.

Exceptions

May throw std::bad_alloc from the std::wstring constructor.

Example

Run this code

#include <iostream>
#include <string>
 
int main()
{
    for (const double f : {23.43, 1e-9, 1e40, 1e-40, 123456789.0})
        std::wcout << "std::wcout: " << f << '\n'
                   << "to_wstring: " << std::to_wstring(f) << "\n\n";
}

Output:

std::wcout: 23.43
to_wstring: 23.430000
 
std::wcout: 1e-09
to_wstring: 0.000000
 
std::wcout: 1e+40
to_wstring: 10000000000000000303786028427003666890752.000000
 
std::wcout: 1e-40
to_wstring: 0.000000
 
std::wcout: 1.23457e+08
to_wstring: 123456789.000000

See also

to_string (C++11)

converts an integral or floating point value to string (function)