对于ascii码的char事实上就是unicode码wchar的首个字节码，

如wchar[20] = "qqqq"; 在内存中排码事实上是char的'q' '\0'这类。因此我们假设自己写unicode码转换为ascii的char，仅仅须要取其首字节就可以，例如以下本人写了一个wchar到char的转换的函数。

因为代码简单，加上了内存泄露測试方式。

#include <stdio.h>

#ifdef _DEBUG

#define DEBUG_CLIENTBLOCK new( _CLIENT_BLOCK, __FILE__, __LINE__)

#else

#define DEBUG_CLIENTBLOCK

#endif

#define _CRTDBG_MAP_ALLOC

#include <stdlib.h>

#include <crtdbg.h>

#include <tchar.h>

#include <Windows.h>

#ifdef _DEBUG

#define new DEBUG_CLIENTBLOCK

#endif

char* UnicodeToMultibyte(WCHAR *wStr)

{

	if (NULL != wStr)

	{

		int nLen = wcslen(wStr);

		char *pStr = new char[nLen + 1];

		int i = 0;

		for (; i < nLen; ++i)

		{

			(pStr)[i] = (char)*(wStr + i);

		}

		(pStr)[i] = '\0';

		printf("%s\n", pStr);

		return pStr;

	}

	return NULL;

}

int main()

{

	_CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF);

	/*char *str = new char[100];*/

	WCHAR wStr[250] = L"qqqqqqqqqqqqq";

	char szTemp[250] = _T("wwwwwwwwwwwww");

	char* pTemp = UnicodeToMultibyte(wStr);

	strcpy(szTemp, pTemp);

	delete pTemp;		//注意，小心内存泄露

	printf("%s\n", szTemp);

	return 0;

}

当然也能够通过windows的转换函数，这个msdn上有具体解释就不解释啦

char* ConvertLPWSTRToLPSTR (LPWSTR lpwszStrIn)

{

	LPSTR pszOut = NULL;

	if (lpwszStrIn != NULL)

	{

		int nInputStrLen = wcslen (lpwszStrIn);  

		// Double NULL Termination

		int nOutputStrLen = WideCharToMultiByte (CP_ACP, 0, lpwszStrIn, nInputStrLen, NULL, 0, 0, 0) + 2;

		pszOut = new char [nOutputStrLen];  

		if (pszOut)

		{

			memset (pszOut, 0x00, nOutputStrLen);

			WideCharToMultiByte(CP_ACP, 0, lpwszStrIn, nInputStrLen, pszOut, nOutputStrLen, 0, 0);

		}

	}

	return pszOut;

}