conversion to _bstr_t - newbie

[Sarath C]

ThatsAlok wrote:

TCHAR szStr[100]; wsprintf(szStr,"%d",100);

I think type defined by TCHAR has dependency to the current build environement(unicode/ MBCS). The compiler will define char array instead of unicode character array (wchar_t)in an MBCS environment. so there is a chance for error. I think, when it is better to declare wchar_t array instead of declaring TCHAR array since we are using wsprintf for formatting. what do u think? SaRath.
"Don't Do Different things... Do Things Differently..."

[antonaras]

Thanks ThatsAlok I'm getting there is almost working how about doubles? Appreciate the help

[ThatsAlok]

SaRath C wrote:

I think type defined by TCHAR has dependency to the current build environement(unicode/ MBCS). The compiler will define char array instead of unicode character array (wchar_t)in an MBCS environment. so there is a chance for error.

Actually TCHAR is defined as :-

#ifdef UNICODE
 #define TCHAR wchar_t
 #else
 #define TCHAR char
 #endif

so you can use in both Character set. plus little mistake from my side too, wsprintf should be written something like this to make it character set independent

wsprintf(szChar,_T("%d"),100);

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers, Alok Gupta VC Forum Q&A :- I/ IV Support CRY- Child Relief and You

[ThatsAlok]

SaRath C wrote:

_bstr_t is a type which can hold unicode string.

you getting very fast :)

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers, Alok Gupta VC Forum Q&A :- I/ IV Support CRY- Child Relief and You

[Sarath C]

You will get the expected string depends on the format specifier you are specifying http://msdn2.microsoft.com/en-us/library/75w45ekt.aspx[^] SaRath.
"Don't Do Different things... Do Things Differently..."

[ThatsAlok]

antonaras wrote:

how about doubles?

use %e format

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers, Alok Gupta VC Forum Q&A :- I/ IV Support CRY- Child Re

[ThatsAlok]

SaRath C wrote:

call strText.AllocSysString(); to convert

there can Memory Leak problem here!

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers, Alok Gupta VC Forum Q&A :- I/ IV Support CRY- Child Relief and You

[antonaras]

Hey ThatsAlok i tried your code and it works fine with integers but i have double valField4; TCHAR szStr2[100]; wsprintf(szStr2,"%e",valField4); _bstr_t bstText2(szStr2); printf("%s\n",(LPCSTR)bstText2); the otput for bstText2 that i get is e why does that happen thanks again

[Viorel]

If you are familiar with STL, you can use one more method:

int i = 1234567;
double d = 123.4567;
_bstr_t s1, s2;

// convert integer
{
    std::ostrstream os;
    os << i << std::ends;
    s1 = os.str();
}
// convert double
{
    std::ostrstream os;
    os << d << std::ends;
    s2 = os.str();
}

[antonaras]

Thanks Viorel i tried your code but i get lots of compilation errors 'ostrstream' : undeclared identifier syntax error : missing ';' before identifier 'os' 'os' : undeclared identifier and so on what i'm doing wrong i have included string is there anything else i need to include thanks

[Viorel]

In order to use these STL features, you have to include a header file:

#include <strstream>

Next, you may receive an "unresolved external symbol" error displayed by the linker. In this case, you have to make one more addition: specify "comsuppwd.lib" in the "Linker --> Input --> Additional Dependencies" configuration option of your project. (In release compilation mode, specify "comsuppw.lib"). You can always see which header file or library is required by analyzing the descriptions in MSDN.

[antonaras]

thanks Viorel is working fine now thanks for all the help

[David Crow]

antonaras wrote:

can i convert integers and doubles to _bstr_t;

Just assign them:

double d;
int x;
_bstr_t str;
str = d;
str = (long) x;

---

"The largest fire starts but with the smallest spark." - David Crow

"Judge not by the eye but by the heart." - Native American Proverb