Conversion of Char and WCHAR in STL

Learning Record:

In STL, the string str naturally corresponds to a string

The wide string wchar corresponds to the wstring

A wide string occupies two bytes

There are three ways to convert the two

1 Windows API conversion function WideCharToMultiByte () with MultiByteToWideChar (). Not suitable for cross-platform use.

2 ATL in ca2w class and CW2A class. Or use the A2W macro with the W2A macro. A little cumbersome and troublesome

3 Use the CRT library functions and methods of use see the following code

#include <string>#include<iostream>#include<locale.h>using namespacestd;stringWs2s (ConstWstring &ws) {    Constwchar_t* Wpchar =Ws.c_str (); size_t ReturnVal=0; size_t wsize=2*ws.size () +1; Char* Pchar =New Char[wsize]; memset (Pchar,0, wsize); wcstombs_s (&returnval,pchar,wsize,wpchar,wsize); stringresult =Pchar;    Delete[] Pchar; returnresult;}int_tmain (intARGC, _tchar*argv[]) {setlocale (Lc_all,"CHS"); wstring ws= L"China Hello, SF*&%*&^%^&SD, this is a test"; stringSS =ws2s (WS); Wcout<< ws <<Endl; cout<< SS <<Endl; return 0;}

Conversion of Char and WCHAR in STL