casting from std::vector<_ty>

[vikasetrx]

any idea how we can cast from std::vector types.

e.g.. i am using the win32 API RegQueryValueEx().

the out buffer it takes should be LPBYTE.

i used the code as shown,

TCHAR * buf = new TCHAR[2];

RegQueryValueEx(................ (BYTE*)buf));

now i want to use a vector instead of TCHAR*.. so what i did is,

std::vector<TCHAR> buf(2);

now i want to use this in the RegQueryValueEx() API, how do i cast it
to LPBYTE... i tried using const_iterator.... the cast doesn't produce
warning or error, but the results are not as desired.

 

[Michael DOUBEZ]

(e-mail address removed) a écrit :

any idea how we can cast from std::vector types.

e.g.. i am using the win32 API RegQueryValueEx().

the out buffer it takes should be LPBYTE.

i used the code as shown,

TCHAR * buf = new TCHAR[2];

RegQueryValueEx(................ (BYTE*)buf));

now i want to use a vector instead of TCHAR*.. so what i did is,

std::vector<TCHAR> buf(2);

now i want to use this in the RegQueryValueEx() API, how do i cast it
to LPBYTE... i tried using const_iterator.... the cast doesn't produce
warning or error, but the results are not as desired.

I don't known about LPBYTE but perhaps it is what you want :

RegQueryValueEx(................ static_cast<LPBYTE*>(&buf.front()) );

Michael

 

[FabioAng]

any idea how we can cast from std::vector types.

e.g.. i am using the win32 API RegQueryValueEx().

the out buffer it takes should be LPBYTE.

i used the code as shown,

TCHAR * buf = new TCHAR[2];

RegQueryValueEx(................ (BYTE*)buf));

now i want to use a vector instead of TCHAR*.. so what i did is,

std::vector<TCHAR> buf(2);

now i want to use this in the RegQueryValueEx() API, how do i cast it
to LPBYTE... i tried using const_iterator.... the cast doesn't produce
warning or error, but the results are not as desired.

See Effective STL book.
Item 16: Know how to pass vector and string data to legacy APIs

std::vector<TCHAR> buf(2);
RegQueryValueEx(................ (BYTE*)&buf[0]));

Bye
Fabio