C++ WCHAR manipulations

Question

I'm developing a tiny Win32 app in C++. I've studied C++ fundamentals long time ago, so now I completely confused because of character strings in C++. There were no `WCHAR` or `TCHAR` only `char` and `String`. After a little investigation I've decided not to use `TCHAR`. My issue is very simple I think, but I can't find clear guide how to manipulate strings in C++. Affected by PHP coding last few years I've expected something simple with strings manipulations and was wrong! Simply, all I need is to put new data to a character string. ``` WCHAR* cs = L"\0"; swprintf( cs, "NEW DATA" ); ``` This was my first attempt. When debugging my app I've investigated that swprintf puts only first 2 chars to my cs var. I've resolved my problem this way: ``` WCHAR cs[1000]; swprintf( cs, "NEW DATA" ); ``` But generally this trick could fail, because in my case new data is not constant value but another variable, that could potentialy be wider, than 1000 chars long. And my code is looks like this: ```…

Accepted Answer

In modern Windows programming, it's OK to just ignore `TCHAR` and instead use `wchar_t` (`WCHAR`) and Unicode UTF-16.

(`TCHAR` is a model of the past, when you wanted to have a single code base, and produce both ANSI/MBCS and Unicode builds changing some preprocessor switches like `_UNICODE` and `UNICODE`.)

In any case, you should use C++ and convenient string classes to simplify your code. You can use `ATL::CString` (which corresponds to `CStringW` in Unicode builds, which are the default since VS2005), or STL's `std::wstring`.

Using `CString`, you can do:

```
CString str1 = L"Some value";
CString str2 = L"Another value";
CString cs;
cs.Format(L"The paths are %s and %s", str1.GetString(), str2.GetString());
```

`CString` also provides proper overloads of `operator+` to concatenate strings (so you don't have to calculate the total length of the resulting string, dynamically allocate a buffer for the destination string or check existing buffer size, call `wcscpy`, `wcscat`, don't forget to release the buffer, etc.)

And you can simply pass instances of `CString` to Win32 APIs expecting `const wchar_t*` (`LPCWSTR/PCWSTR`) parameters, since `CString` offers an implicit conversion operator to `const wchar_t*`.

C++ WCHAR manipulations

Solution

Problem