#include <stdafx.h>
#include <Windows.h>


bool AsciiToUnicodeChar(const char * str, wchar_t * buffer, int lenOfBuffer)
{
	if (lenOfBuffer < 4)
		return false;
	int len = lenOfBuffer - 2;
	DWORD  num = MultiByteToWideChar(CP_ACP, 0, str, -1, NULL, 0); //num为宽字符的个数
	if ((DWORD)len < num)
		num = len;

	buffer[num] = L'\0';
	//memset(buffer, 0, sizeof(wchar_t)*(num + 1));
	MultiByteToWideChar(CP_ACP, 0, str, (int)strlen(str), buffer, num);
	return true;
}

//调用者释放返回字符串的内存
 wchar_t * AsciiToUnicodeChar(const char * str)
{
	DWORD  num = MultiByteToWideChar(CP_ACP, 0, str, -1, NULL, 0); //num为宽字符的个数

	wchar_t * buffer = new wchar_t[num + 1];
	memset(buffer, 0, sizeof(wchar_t)*(num + 1));
	MultiByteToWideChar(CP_ACP, 0, str, (int)strlen(str), buffer, num);
	return buffer;
}

 //TODO:改成返回bool
 char* UnicodeToAscii(const wchar_t * str, char * buffer, int lenOfBuffer)
 {
	 if (lenOfBuffer <= 0 || buffer == 0 || str == 0)
		 return 0;

	 memset(buffer, 0, lenOfBuffer);
	 lenOfBuffer--;
	 DWORD  num = WideCharToMultiByte(CP_ACP, 0, str, -1, NULL, 0, NULL, 0);
	 if (num >= (DWORD)lenOfBuffer)
		 return NULL;

	 WideCharToMultiByte(CP_ACP, 0, str, -1, buffer, num, NULL, NULL);
	 return buffer;
 }

//调用者负责释放返回的内存
char* UnicodeToAscii(const wchar_t * str)
{
	DWORD  num = WideCharToMultiByte(CP_ACP, 0, str, -1, NULL, 0, NULL, 0);
	char * buffer = new char[num + 1];
	memset(buffer, 0, sizeof(char)*(num + 1));

	WideCharToMultiByte(CP_ACP, 0, str, -1, buffer, num, NULL, NULL);
	return buffer;
}