Hi,

I have to a project which I am converting it to Unicode. I am
getting following error. I am not sure How to fix it.

error C2664: 'LogFile::LogToFile' : cannot convert parameter 1 from
'const unsigned short [65]' to 'std::string'

The code is
#define MAIN_LOG_FILE ".\\ABC.log"

Defination LogToFile(std::string message, std::string fileName);

I am calling this LogToFile("My Name", MAIN_LOG_FILE)

I have tried using "L" and "_T" It is not working.

Can you please help?
Thanks

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On Aug 1, 7:28 pm, Trups <Samant.Tru...@gmail.com> wrote:

> error C2664: 'LogFile::LogToFile' : cannot convert parameter 1 from
> 'const unsigned short [65]' to 'std::string'
>
> The code is
> #define MAIN_LOG_FILE ".\\ABC.log"
>
> Defination LogToFile(std::string message, std::string fileName);
>
> I am calling this LogToFile("My Name", MAIN_LOG_FILE)
>
> I have tried using "L" and "_T" It is not working.
>
> Can you please help?
> Thanks

Is that the real code you are using? "L" not "_T" would help here
why he is trying to reference the 1st parameter as an unsigned
short[65]?
something tells me that you haven't gave us the "real" code please re-
post


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Trups wrote:

> Hi,
>
> I have to a project which I am converting it to Unicode. I am
> getting following error. I am not sure How to fix it.
>
> error C2664: 'LogFile::LogToFile' : cannot convert parameter 1 from
> 'const unsigned short [65]' to 'std::string'
>
> The code is
> #define MAIN_LOG_FILE ".\\ABC.log"
>
> Defination LogToFile(std::string message, std::string fileName);
>
> I am calling this LogToFile("My Name", MAIN_LOG_FILE)
>
> I have tried using "L" and "_T" It is not working.

Just looking at the code everything looks fine for
me "My Name" and MAIN_LOG_FILE is const char * which
the compiler casts into std::string behind your back
and would call LogToFile(...) with that.

I assume you use a magic compiler switch which tells it
to treat all string literals as const wchar_t *. Well
in that case it would have to be.

LogToFile(const std::wstring &, const std::wstring & fileName);

(The const & is optional, but I think that's what you intended).

But then you're running into trouble with the fileName argument.
I'm not aware of any fstream.open or (f|)open method/function
which takes a const wchar_t * argument, but may be that's just
because of my limited knowledge.

You could make it a templated function like...

<snip>

// Transforms a std::basic_string<CharT> to std::basic_string<char>
// A lot of std::locale and facet<codecvt<...> > magic would be required
// in the real world.

template<class CharT>
std::basic_string<char> str_conv(const std::basic_string<CharT> & s) {
return std::basic_string<char>("dummy_for_code_conversion ");
}

// Specialization for CharT==char
//

template<>
std::basic_string<char> str_conv<char>(const std::basic_string<char> & s) {
return s;
}

// This one opens a file. Logs the string
// and closes it. May be it would be better
// to pass around a ref to basic_ofstream<..>
// instead of the file name. And in that case
// You could simply use the

// std::basic_ostream<CharT> &
// operator<<(std::basic_ostream & os,
// const std::basic_string<CharT> &s);

// operator anyway.

template<class CharT>
bool LogToFile(const std::basic_string<CharT> & s,
const std::basic_string<CharT> & fn) {
std::basic_ofstream<CharT> fs(str_conv(fn).c_str());
fs.imbue(std::locale("en_US.utf-8"));
fs << s << std::endl;
return true;
};

// an overload that transforms const CharT * to
// std::basic_string<CharT>.

template<class CharT>
bool LogToFile(const CharT * s,const CharT * fn) {
return
LogToFile(std::basic_string<CharT>(s),
std::basic_string<CharT>(fn));
}

</snip>

HTH

O.


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On Aug 1, 7:28 pm, Trups <Samant.Tru...@gmail.com> wrote:
> Hi,
>
> I have to a project which I am converting it to Unicode. I am
> getting following error. I am not sure How to fix it.
>
> error C2664: 'LogFile::LogToFile' : cannot convert parameter 1 from
> 'const unsigned short [65]' to 'std::string'
>
> The code is
> #define MAIN_LOG_FILE ".\\ABC.log"
>
> Defination LogToFile(std::string message, std::string fileName);
>
> I am calling this LogToFile("My Name", MAIN_LOG_FILE)
>
> I have tried using "L" and "_T" It is not working.
>
> Can you please help?

You can use something like this:

#include <tchar.h> // MS-specific

typedef std::basic_string< TCHAR > tstring;

LogToFile(tstring const& message, tstring const& fileName);

Then, add _T() around string literals where appropriate, e.g:

#define MAIN_LOG_FILE _T(".\\ABC.log")

LogToFile(_T("My Name"), MAIN_LOG_FILE)

This way you can compile both Unicode and non-Unicode versions of your
program from a single set of source files. Just define _UNICODE when
compiling w/ Unicode support.

--
Cheers,
Alex


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