How do I convert a TCHAR
array to std::string
(not to std::basic_string
)?

- 44,692
- 7
- 66
- 118

- 2,885
- 8
- 40
- 54
-
11You realize std::string is just a typedef for a std::basic_string
? – Dark Falcon Jun 09 '11 at 10:37 -
And do you want to convert a specifically Unicode or MBCS TCHAR (i.e. really WCHAR or CHAR) into a std::string (i.e. char) always, or convert CHAR to string and WCHAR to wstring, or something else? – Rup Jun 09 '11 at 10:39
6 Answers
TCHAR
is just a typedef that, depending on your compilation configuration, either defaults to char
or wchar_t
.
Standard Template Library supports both ASCII (with std::string
) and wide character sets (with std::wstring
). All you need to do is to typedef String as either std::string or std::wstring depending on your compilation configuration. To maintain flexibility you can use the following code:
#ifndef UNICODE
typedef std::string String;
#else
typedef std::wstring String;
#endif
Now you may use String
in your code and let the compiler handle the nasty parts. String will now have constructors that lets you convert TCHAR
to std::string
or std::wstring
.
-
3problem is I have to call a interface which accepts std::string so i cant send std::wstring :( – ashmish2 Jun 09 '11 at 10:41
-
See [this question](http://stackoverflow.com/questions/4804298/c-how-to-convert-wstring-into-string/4804506#4804506) for how to convert from wstring to string. – kbjorklu Jun 09 '11 at 10:55
-
@ebyrob: The same thing Alok Save did with std::string and std::wstring you'd also have to do with std::cout and std::wcout. – antred May 30 '14 at 12:35
-
2@antred so `typedef std::wcout std_tcout` and `std_tstring` etc? I can't... get myself to facade a standard like that. Then again, I used to do it for graphics operations all the time. Why not `std::basic_string
` for the first half of the typedef of string is there a discernible difference? – May 30 '14 at 13:50 -
@ashmish2 http://stackoverflow.com/questions/2573834/c-convert-string-or-char-to-wstring-or-wchar-t shows conversion between `std::wstring` and `std::string`, assuming UTF-8, but there are other scenarios. Considering this is VS, I'd just try to stick to `W2A()` and `A2W()` in most cases though. – May 30 '14 at 13:56
My answer is late, I'll admit that, but with the answers of 'Alok Save' and some research I've found a good way! (Note: I didn't test this version a lot, so it might not work in every case, but from what I tested it should):
TCHAR t = SomeFunctionReturningTCHAR();
std::string str;
#ifndef UNICODE
str = t;
#else
std::wstring wStr = t;
str = std::string(wStr.begin(), wStr.end());
#endif
std::cout << str << std::endl; //<-- should work!

- 122
- 2
- 6
-
It works only for 7-bit ASCII, but prints garbage for other characters. – palota Feb 11 '16 at 10:35
TCHAR type is char
or wchar_t
, depending on your project settings.
#ifdef UNICODE
// TCHAR type is wchar_t
#else
// TCHAR type is char
#endif
So if you must use std::string
instead of std::wstring
, you should use a converter function. I may use wcstombs
or WideCharToMultiByte
.
TCHAR * text;
#ifdef UNICODE
/*/
// Simple C
const size_t size = ( wcslen(text) + 1 ) * sizeof(wchar_t);
wcstombs(&buffer[0], text, size);
std::vector<char> buffer(size);
/*/
// Windows API (I would use this)
std::vector<char> buffer;
int size = WideCharToMultiByte(CP_UTF8, 0, text, -1, NULL, 0, NULL, NULL);
if (size > 0) {
buffer.resize(size);
WideCharToMultiByte(CP_UTF8, 0, text, -1, static_cast<BYTE*>(&buffer[0]), buffer.size(), NULL, NULL);
}
else {
// Error handling
}
//*/
std::string string(&buffer[0]);
#else
std::string string(text);
#endif

- 30,738
- 21
- 105
- 131

- 7,560
- 2
- 33
- 49
-
I tried it, got: error C2664: 'std::basic_string<_Elem,_Traits,_Ax>::basic_string(const std::basic_string<_Elem,_Traits,_Ax> &)' : cannot convert parameter 1 from 'TCHAR [50]' to 'const std::basic_string<_Elem,_Traits,_Ax> &' – john k Jan 04 '13 at 01:23
-
1@user396483: I just tried it in VS2012. Code: [link](http://store.naszta.hu/main/example01.cpp). – Naszta Jan 04 '13 at 21:34
TCHAR is either char or wchar_t, so a
typedef basic_string<TCHAR> tstring;
is one way of doing it.
The other is to skip char
altogether and just use std::wstring
.

- 90,663
- 31
- 146
- 203
Simple!
std::string tcharToChar(TCHAR* buffer)
{
char *charBuffer = NULL;
std::string returnValue;
int lengthOfbuffer = lstrlenW(buffer);
if(buffer!=NULL)
{
charBuffer = (char*)calloc(lengthOfbuffer+1,sizeof(char));
}
else
{
return NULL;
}
for (int index = 0;
index < lengthOfbuffer;
index++)
{
char *singleCharacter = (char*)calloc(2,sizeof(char));
singleCharacter[0] = (char)buffer[index];
singleCharacter[1] = '\0';
strcat(charBuffer, singleCharacter);
free(singleCharacter );
}
strcat(charBuffer, "\0");
returnValue.append(charBuffer);
free(charBuffer);
return returnValue;
}

- 21
- 1
- 4
-
Now you have an owning raw pointer you need to clean up. Why not return a `std::string` instead? Edit : You also leak a ton of tiny buffers with `singleCharacter`. This solution is not acceptable as-is. There is no need to dynamically allocate for `singleCharacter` and I don't see the need for `strcat` to write a string character-by-character. – François Andrieux Apr 03 '19 at 12:47
-
i accept it was a lazy solution. i have corrected the leaks and returned a std::string. Thanks for your input. – user1567759 Jan 21 '21 at 07:18
-
With the changes the answer isn't strictly harmful, so I removed my downvote. But it is still not a very good solution. There is no need for `strcat` or `singleCharacter`, you can just push the last character to the position `index` of `charBuffer`. You also don't need to allocate for `charBufffer` because `std::string` already has a character buffer you can use. Manual memory management has fallen heavily out of favor in modern C++ and should generally not be part of recommended solutions unless absolutely necessary. – François Andrieux Jan 21 '21 at 15:49
-
`calloc`, `malloc`, etc. are C memory allocation functions and are not as easy to use in C++. They do not start the lifetime of objects. `new` should be used instead, but even then `new` is also discouraged. `std::vector` and `std::make_unique` should replace the vast majority of manual memory management. – François Andrieux Jan 21 '21 at 15:52
Quick and dirty solution :
TCHAR str[256] = {};
// put something in str...
// convert to string
std::string strtmp(&str[0], &str[255]);
std::cout << strtmp << std::endl;

- 3,676
- 2
- 30
- 34
-
This will cause unexpected behaviour if the original string contains any non-ascii characters – M.M Mar 31 '20 at 04:42
-
1I believe this will always produce an `std::string` with a length of 255 characters, even when the string contains a null terminator. `std::string` can contain nulls, specifically if you use the range based constructor like in this case. – François Andrieux Jan 21 '21 at 15:46