Encoding转UTF8,该怎么处理

using namespace System;using namespace System::Text;using namespace System::Collections;int main(){   // Create a UTF-8 encoding.   UTF8Encoding^ utf8 = gcnew UTF8Encoding;   // A Unicode string with two characters outside an 8-bit code range.   String^ unicodeString = L"This unicode string contains two characters with codes outside an 8-bit code range, Pi (\u03a0) and Sigma (\u03a3).";   Console::WriteLine( "Original string:" );   Console::WriteLine( unicodeString );   // Encode the string.   array<Byte>^encodedBytes = utf8->GetBytes( unicodeString );   Console::WriteLine();   Console::WriteLine( "Encoded bytes:" );   IEnumerator^ myEnum = encodedBytes->GetEnumerator();   while ( myEnum->MoveNext() )   {      Byte b = safe_cast<Byte>(myEnum->Current);      Console::Write( "[{0}]", b );   }   Console::WriteLine();   // Decode bytes back to string.   // Notice Pi and Sigma characters are still present.   String^ decodedString = utf8->GetString( encodedBytes );   Console::WriteLine();   Console::WriteLine( "Decoded bytes:" );   Console::WriteLine( decodedString );}
------解决方案--------------------------------------------------------

// 文本编码转换
bool Ansi2Unicode(const std::string& ansi, std::wstring& uni)
{
 if(ansi.size() == 0)
 {
   uni.resize(0);
   return true;
 }

   // 预转换，得到所需空间的大小
 int wcsLen = MultiByteToWideChar(CP_ACP, NULL, ansi.c_str(), ansi.size(), NULL, 0);

 wchar_t* uni_Buff = new wchar_t[wcsLen + 1];
 memset(uni_Buff, 0x00, sizeof(wchar_t) * (wcsLen + 1));

   // 转换
 MultiByteToWideChar(CP_ACP, NULL, ansi.c_str(), ansi.size(), uni_Buff, wcsLen);

 uni = uni_Buff;
 delete[] uni_Buff;
 uni_Buff = NULL;
 return true;
}

bool Unicode2Ansi(const std::wstring& unicode, int size, std::string& ansi)
{
 if(unicode.size() == 0)
 {
   ansi.resize(0);
   return true;
 }

   // 预转换，得到所需空间的大小，这次用的函数和上面名字相反
   int ansiLen = WideCharToMultiByte(CP_ACP, NULL, unicode.c_str(), size, NULL, 0, NULL, NULL);

 char* ansiBuff = new char[ansiLen + 1];
 memset(ansiBuff, 0x00, (ansiLen + 1));

   //unicode版对应的strlen是wcslen
   WideCharToMultiByte(CP_ACP, NULL, unicode.c_str(), size, ansiBuff, ansiLen, NULL, NULL);

 ansi = ansiBuff;
 delete[] ansiBuff;
 ansiBuff = NULL;
 return true;
}

bool Utf8ToUnicode(const std::string& utf8, std::wstring& unicode)
{
 if (utf8.size() == 0)
 {
   unicode.resize(0);
   return true;
 }

   //预转换，得到所需空间的大小
   int wcsLen = MultiByteToWideChar(CP_UTF8, NULL, utf8.c_str(), utf8.size(), NULL, 0);

 wchar_t* unicode_buf = new wchar_t[wcsLen + 1];

 memset(unicode_buf, 0x00, sizeof(wchar_t) * (wcsLen + 1));

   //转换
   MultiByteToWideChar(CP_UTF8, NULL, utf8.c_str(), utf8.size(), unicode_buf, wcsLen);

 unicode = unicode_buf;

 delete[] unicode_buf;
 unicode_buf = NULL;
 return true;
}

bool Unicode2Utf8(const std::wstring& unicode, int size, std::string& utf8)
{
 if (unicode.size() == 0)
 {
   utf8.resize(0);
   return true;
 }

   //预转换，得到所需空间的大小，这次用的函数和上面名字相反
   int u8Len = WideCharToMultiByte(CP_UTF8, NULL, unicode.c_str(), size, NULL, 0, NULL, NULL);

 char* utf8_buff = new char[u8Len + 1];
 memset(utf8_buff, 0x00, u8Len + 1);
   //转换
   //unicode版对应的strlen是wcslen
   WideCharToMultiByte(CP_UTF8, NULL, unicode.c_str(), size, utf8_buff, u8Len, NULL, NULL);