codecvt::in
Converts an external representation of a sequence of Bytes to an internal representation of a sequence of CharTypes.
result in(
StateType& _State,
const Byte* _First1,
const Byte* _Last1,
const Byte*& _Next1,
CharType* _First2,
CharType* _Last2,
CharType*& _Next2,
) const;
Parameters
_State
The conversion state that is maintained between calls to the member function._First1
Pointer to the beginning of the sequence to be converted._Last1
Pointer to the end of the sequence to be converted._Next1
Pointer beyond the end of the converted sequence to the first unconverted character._First2
Pointer to the beginning of the converted sequence._Last2
Pointer to the end of the converted sequence._Next2
Pointer to the CharType that comes after the last converted Chartype to the first unaltered character in the destination sequence.
Return Value
A return that indicates the success, partial success or failure of the operation. The function returns:
codecvt_base::error if the source sequence is ill formed.
codecvt_base::noconv if the function performs no conversion.
codecvt_base::ok if the conversion succeeds.
codecvt_base::partial if the source is insufficient or if the destination is not large enough for the conversion to succeed.
Remarks
_State must represent the initial conversion state at the beginning of a new source sequence. The function alters its stored value, as needed, to reflect the current state of a successful conversion. After a partial conversion, _State must be set so as to allow the conversion to resume when new characters arrive.
The member function returns do_in(_State, _First1, _Last1, _Next1, First2, _Llast2, _Next2).
Example
// codecvt_in.cpp
// compile with: /EHsc
#define _INTL
#include <locale>
#include <iostream>
using namespace std;
#define LEN 90
int main( )
{
char* pszExt = "This is the string to be converted!";
wchar_t pwszInt [LEN+1];
memset(&pwszInt[0], 0, (sizeof(wchar_t))*(LEN+1));
const char* pszNext;
wchar_t* pwszNext;
mbstate_t state = {0};
locale loc("C");//English_Britain");//German_Germany
int res = use_facet<codecvt<wchar_t, char, mbstate_t> >
( loc ).in( state,
pszExt, &pszExt[strlen(pszExt)], pszNext,
pwszInt, &pwszInt[strlen(pszExt)], pwszNext );
pwszInt[strlen(pszExt)] = 0;
wcout << ( (res!=codecvt_base::error) ? L"It worked! " : L"It didn't work! " )
<< L"The converted string is:\n ["
<< &pwszInt[0]
<< L"]" << endl;
exit(-1);
}
It worked! The converted string is: [This is the string to be converted!]
Requirements
Header: <locale>
Namespace: std