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codecvt::length

Determines how many Bytes from a given sequence of external Bytes produce not more than a given number of internal CharTypes and returns that number of Bytes.

int length(
      const StateType& _State,
     const Byte* _First1, 
     const Byte* _Last1,
     size_t _Len2
) const;

Parameters

  • _State
    The conversion state that is maintained between calls to the member function.

  • _First1
    Pointer to the beginning of the external sequence.

  • _Last1
    Pointer to the end of the external sequence.

  • _Len2
    The maximum number of Bytes that can be returned by the member function.

Return Value

An integer that represents a count of the maximum number of conversions, not greater than _Len2, defined by the external source sequence at [_First1, _Last1).

Remarks

The member function returns do_length(_State, _First1, _Last1, _Len2).

Example

// codecvt_length.cpp
// compile with: /EHsc
#define _INTL
#include <locale>
#include <iostream>
using namespace std;
#define LEN 90
int main( )   
{
   char* pszExt = "This is the string whose length is to be measured!";
   mbstate_t state = {0};
   locale loc("C");//English_Britain");//German_Germany
   int res = use_facet<codecvt<wchar_t, char, mbstate_t> >
     ( loc ).length( state,
          pszExt, &pszExt[strlen(pszExt)], LEN );
   cout << "The length of the string is: ";
   wcout << res;
   cout << "." << endl;
   exit(-1);
}

The length of the string is: 50.

Requirements

Header: <locale>

Namespace: std

See Also

Concepts

codecvt Class

codecvt Members