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Is that normal that I got an error like that :
error C2679: binary '=' : no operator defined which takes a right-hand operand of type
'class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > (__cdecl *)(void)'
(or there is no acceptable conversion)
The code look like :
std::string a;
a = (*returnMyString);
First answer: NO not normal
If it is an external (usually MS) dll - you are dealing with null-terminated char *.
If it's OLE , then you've likely got BSTR *.
Not <string> :D
as in std::string
If you're calling between C++ DLLs from the same compiler, you can return strings quite happily...the best thing if you're making a C DLL is to get them to supply a buffer and a length, then fill it up a la strncpy().
Watch for the buffer overruns, though!
Well you are both too good in C for me because I think you have answer my question with too much hard word because I do not understand what to change to have no error...
And can we put whole class in a DLL ?
I call the dll to the string like that :
Code:std::string sPass;
sPass =(*PasswordMaker);
and I got :
Code:error C2679: binary '=' : no operator defined which takes a right-hand operand of type 'class std::basic_string<char,st
ruct std::char_traits<char>,class std::allocator<char> > (__cdecl *)(void)' (or there is no acceptable conversion)
warning C4550: expression evaluates to a function which is missing an argument list
Maybe try this:
PHP Code:std::string sPass;
sPass =(*PasswordMaker)();
THX but that produce that error now :
THX but that produce that error now :
THX but that produce that error now :
http://www.vbforums.com/attachment.p...postid=1101347
I have that when the exe close.
How is your DLL written? What's the code for PasswordMaker()?
Oh, are you freeing the DLL when you have used it? Use FreeLibrary() to unload the DLL before quitting the program.
PHP Code://Use the DLL
//...........
//Free the DLL
FreeLibrary(hDLL);
C++ doesn't have something like in vb unload() or a function who is exectuted when the program close ?
C++ doesn't have something like in vb unload() or a function who is exectuted when the program close ?
Here is in the dll the code of the password function, the freelibrary didn't solve the problem.
PHP Code:std::string __declspec( dllexport )PasswordMaker()
{
char cChar; //Contain the character that the user have pressed
std::string sPass; //Contain all character
int iNombreChar = 0; //Number of character that the user have pressed
//Loop until the user press enter
while(true)
{
//Get character one by one
cChar = getch();
//Only if the number that the user put is bigger than 1 you can erase
if (iNombreChar > 0)
{
if( cChar == 8)
{
//Erase the character in the String
sPass = sPass.substr(0,sPass.length() -1);
//Erase the character at the screen
std::cout << (char)(8) << char(32) << char(8);
iNombreChar--;
}//End if
}//End if
//Put stars and not the character
if (cChar != 13 && cChar != 8)
{
sPass += cChar;
std::cout << "*";
iNombreChar ++;
}//End if
//If the user press ENTER than we have done with the password creation
else if (cChar == 13)
break;
}//End for while(true)
return sPass;
}//End PasswordMaker
C++ doesn't have something like in vb unload() or a function who is exectuted when the program close ?
Here is in the dll the code of the password function, the freelibrary didn't solve the problem.
PHP Code:std::string __declspec( dllexport )PasswordMaker()
{
char cChar; //Contain the character that the user have pressed
std::string sPass; //Contain all character
int iNombreChar = 0; //Number of character that the user have pressed
//Loop until the user press enter
while(true)
{
//Get character one by one
cChar = getch();
//Only if the number that the user put is bigger than 1 you can erase
if (iNombreChar > 0)
{
if( cChar == 8)
{
//Erase the character in the String
sPass = sPass.substr(0,sPass.length() -1);
//Erase the character at the screen
std::cout << (char)(8) << char(32) << char(8);
iNombreChar--;
}//End if
}//End if
//Put stars and not the character
if (cChar != 13 && cChar != 8)
{
sPass += cChar;
std::cout << "*";
iNombreChar ++;
}//End if
//If the user press ENTER than we have done with the password creation
else if (cChar == 13)
break;
}//End for while(true)
return sPass;
}//End PasswordMaker