Hi,
I think this is slightly OT, (I am not certain that Macros are part of the
standard), but I am hopping that someone could help.
I am trying to use a language file in my system.
the format of the file would be something like
[option]
open=Open
close=Close
....
and so on.
Now I want to create some macros that I could use all over the place in all
the functions that would output text to the screen.
something like
SetMenuText( LANG_CLOSE ); or DisplayMessage( LANG_HELLOWORLD ); and so one
....
where the macro would represent...
#define LANG_CLOSE GetLanguagefile ( "option", "close",
"Close" );
#define LANG_HELLOWORLD GetLanguagefile ( "option", "hellow", "Hello
world..." );
but my problem is the return value, I would like to return a const char* or
even a char* but I don't think it is possible to return them directly.
I could have a global char *, char * g_szReturn = NULL; but is it really
safe to use it that way?
I need to return the function otherwise the macro are not very useful really
because I would have to add 2 or three lines of code every time.
Like
char szText[1024];
if( GetLanguagefile ( "option", "close", "Close", szText, 1024 ) ){
SetMenuText( szText );
}
Any ideas how I could safely return a const char* or char *?
Many thanks.
Simon 8 4580
"Simon" <sp********@sch oolsofafrica.co m> wrote in message
news:2h******** ****@uni-berlin.de... Hi,
I think this is slightly OT, (I am not certain that Macros are part of the standard), but I am hopping that someone could help.
Macros are part of the standard. I am trying to use a language file in my system. the format of the file would be something like
[option] open=Open close=Close ... and so on.
Now I want to create some macros that I could use all over the place in
all the functions that would output text to the screen.
something like
SetMenuText( LANG_CLOSE ); or DisplayMessage( LANG_HELLOWORLD ); and so
one ...
where the macro would represent...
#define LANG_CLOSE GetLanguagefile ( "option", "close", "Close" ); #define LANG_HELLOWORLD GetLanguagefile ( "option", "hellow", "Hello world..." );
No reason for macros, inline functions would be better. but my problem is the return value, I would like to return a const char*
or even a char* but I don't think it is possible to return them directly. I could have a global char *, char * g_szReturn = NULL; but is it really safe to use it that way?
Not really, its obscure and therefore dangerous. I need to return the function otherwise the macro are not very useful
really because I would have to add 2 or three lines of code every time. Like
char szText[1024]; if( GetLanguagefile ( "option", "close", "Close", szText, 1024 ) ){ SetMenuText( szText ); }
Any ideas how I could safely return a const char* or char *?
Don't, return a string instead.
#include <string>
inline std::string LANG_CLOSE()
{
return GetLanguagefile ( "option", "close", "Close" );
}
SetMenuText(LAN G_CLOSE().c_str ());
john
Thanks for your reply, Macros are part of the standard.
ah, thanks.
Don't, return a string instead.
#include <string>
inline std::string LANG_CLOSE() { return GetLanguagefile ( "option", "close", "Close" ); }
SetMenuText(LAN G_CLOSE().c_str ());
But could i not go a step further and still use my Macro?
#define LANG_CLOSE GetLanguagefile ( "option", "close", "Close" ).c_str() john
Simon.
"Simon" <sp********@sch oolsofafrica.co m> wrote in message
news:2h******** ****@uni-berlin.de... Thanks for your reply,
Macros are part of the standard.
ah, thanks.
Don't, return a string instead.
#include <string>
inline std::string LANG_CLOSE() { return GetLanguagefile ( "option", "close", "Close" ); }
SetMenuText(LAN G_CLOSE().c_str ());
But could i not go a step further and still use my Macro?
#define LANG_CLOSE GetLanguagefile ( "option", "close", "Close" ).c_str()
Only if GetLanguageFile returns a std::string. My inline function would work
whether GetLanguageFile returns char*, const char* or std::string.
But why use a macro? They have no advantage in this case.
john But could i not go a step further and still use my Macro?
#define LANG_CLOSE GetLanguagefile ( "option", "close", "Close" ).c_str()
Only if GetLanguageFile returns a std::string. My inline function would
work whether GetLanguageFile returns char*, const char* or std::string.
I am not sure I follow, GetLanguagefile (...) will return a string in both
cases. But why use a macro? They have no advantage in this case.
Just curious really. If I could cut out the '.c_str()' it would be a bonus. john
Simon
"Sims" <si*********@ho tmail.com> wrote in message
news:2h******** ****@uni-berlin.de... But could i not go a step further and still use my Macro?
#define LANG_CLOSE GetLanguagefile ( "option", "close",
"Close" ).c_str() Only if GetLanguageFile returns a std::string. My inline function would
work whether GetLanguageFile returns char*, const char* or std::string.
I am not sure I follow, GetLanguagefile (...) will return a string in both cases.
A std::string can be implicitly created from a char* or const char*. This
would happen with my inline function if GetLanguageFile happened to return a
char* or const char*. I just mentioned this because I wasn't sure if
GetLanguageFile was a function you are writing or not. If you are writing it
then you should make it return a std::string. But why use a macro? They have no advantage in this case.
Just curious really. If I could cut out the '.c_str()' it would be a
bonus.
Fair enough.
john
> > A std::string can be implicitly created from a char* or const char*. This would happen with my inline function if GetLanguageFile happened to return
a char* or const char*. I just mentioned this because I wasn't sure if GetLanguageFile was a function you are writing or not. If you are writing
it then you should make it return a std::string.
Yes it is my function. So i guess i will make it return std:string But why use a macro? They have no advantage in this case.
Just curious really. If I could cut out the '.c_str()' it would be a
bonus.
Fair enough.
john
Thanks for your help.
Simon
My Suggestion:
struct Language
{
char* pOpen;
char* pClose;
char* pRead;
char* pWrite;
};
const Language English = {
"Open",
"Close",
"Read",
"Write" };
const Language Irish = {
"Oscail",
"Dún",
"Léigh",
"Scríobh" };
const Language* pCurrentLanguag e = &English; //Default to English
void SetLanguage(con st Language* const NewLanguage)
{
pCurrentLanguag e = NewLanguage;
}
int main(void)
{
SetLanguage(&En glish);
cout << pCurrentLanguag e.pOpen;
SetLanguage(&Ir ish);
cout << pCurrentLanguag e.pOpen;
}
You may consider setting "SetLanguag e" to take an enum instead of a pointer,
whatever tickles your fancy. I myself like this way!
Hope that helps.
-JKop
And once again I have missed the point!!
You can have language file like this:
char* pLoadedLanguage = "Open\0Close\0R ead\0Write";
Language MakeLanguageStr uct(const char* pLoadedLanguage )
{
Language NewLanguage;
NewLanguage.pOp en = pLoadedLanguage ;
while (pLoadLanguage +=1) {}
pLoadLanguage +=1;
NewLanguage.pCl ose = pLoadedLanguage ;
while (pLoadLanguage +=1) {}
pLoadLanguage +=1;
NewLanguage.pRe ad = pLoadedLanguage ;
while (pLoadLanguage +=1) {}
pLoadLanguage +=1;
Language.pWrite = pLoadedLanguage ;
return NewLanguage;
}
Or something to that effect!!
-JKop This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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