converting narrow string to wide string

user_682662 0
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How can i convert a narrow string to a wide string ?

I have tried this method :

string myName;
getline( cin , myName );
wstring printerName( L(myName) );  // error C3861: 'L': identifier not found
wchar_t* WprinterName = printerName.c_str(); // error C2440: 'initializing' : cannot convert from 'const wchar_t *' to 'wchar_t *'

But i get errors as listed above.

Why do i get these errors ? How can i fix them ?

Is there any other method of directly converting a narrow string to a wide string ?

unicode visual-c++ c++ string
9 Answers

The original question of this thread was: "How can i convert a narrow string to a wide string?"

However, from the example code given in the question, there seems to be no conversion necessary. Rather, there is a compiler error due to the newer compilers deprecating something that used to be okay. Here is what I think is going on:

    // wchar_t* wstr = L"A wide string";     // Error: cannot convert from 'const wchar_t *' to 'wchar_t *'

wchar_t const* wstr = L"A wide string";             // okay
const wchar_t* wstr_equivalent = L"A wide string";  // also okay

The c_str() seems to be treated the same as a literal, and is considered a constant (const). You could use a cast. But preferable is to add const.

The best answer I have seen for converting between wide and narrow strings is to use std::wstringstream. And this is one of the answers given to C++ Convert string (or char*) to wstring (or wchar_t*)

You can convert most anything to and from strings and wide strings using stringstream and wstringstream.

user_37361620

This article published on the MSDN Magazine 2016 September issue discusses the conversion in details using Win32 APIs.

Note that using MultiByteToWideChar() is much faster than using the std:: stuff on Windows.

user_16298210

Use mbtowc():

string myName;
wchar_t wstr[BUFFER_SIZE];

getline( cin , myName );
mbtowc(wstr, myName, BUFFER_SIZE);
user_35468360
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