C++ 从std::string转换为LPCWSTR

LPCWSTR stringToLPCWSTR(std::string orig)
 {
	 size_t origsize = orig.length() + 1;
	     const size_t newsize = 100;
	     size_t convertedChars = 0;
	 wchar_t* wcstring = (wchar_t*)malloc(sizeof(wchar_t) * (orig.length() - 1));
	 mbstowcs_s(&convertedChars, wcstring, origsize, orig.c_str(), _TRUNCATE);
	
		 return wcstring;
}