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MBCS/Unicode enabled C++ string class.

TCHAR, the generic text mapping data type. This is Microsoft specific extension and is not ANSI-compatible. I have used this extension to create my small prototype MBCS/Unicode compatible class. This class consists of all the basic functionality required to represent a minimal string class. I have given the name for this class as "CStringUNI". 
// Header File
#pragma once

const int INIT_ALLOC_SIZE = 10;

class CStringUNI
{
private:
 TCHAR *m_szBuffer;
 TCHAR *AllocateMemory(size_t size);

public:
 CStringUNI();
 CStringUNI(const CStringUNI&);
 CStringUNI(const TCHAR*);
 CStringUNI& operator=(const TCHAR*);
 CStringUNI& operator=(const CStringUNI&);
 CStringUNI& operator+=(const CStringUNI&);
 
 // Access Operator
 TCHAR operator[](const size_t n)const;

 TCHAR *GetBuffer() const;

 bool operator==(const TCHAR*) const;
 bool operator==(const CStringUNI&) const;
 virtual ~CStringUNI();

 friend CStringUNI operator+(const CStringUNI& lhs, const CStringUNI& rhs);
};

// CPP file, the actual implemenation file.

#include "StdAfx.h"
#include "StringUNI.h"
#include &ltstring.h&gt

TCHAR *CStringUNI::AllocateMemory(size_t size)
{
 m_szBuffer = new TCHAR[size];

 return m_szBuffer;
}

CStringUNI::CStringUNI()
{
 m_szBuffer = NULL;
}

CStringUNI::CStringUNI(const CStringUNI& source)
{
 const size_t nSizeSource = _tcslen(source.m_szBuffer);
 AllocateMemory(nSizeSource + 1);
 memset(m_szBuffer, 0, nSizeSource);
 _tcscpy(m_szBuffer, source.m_szBuffer);
}

CStringUNI::CStringUNI(const TCHAR* source)
{
 AllocateMemory(_tcslen(source)+ 1);
 memset(m_szBuffer, 0, _tcslen(source)+ 1);
 _tcscpy(m_szBuffer, source);
}

CStringUNI& CStringUNI::operator=(const TCHAR* source)
{
 size_t nSourcelen = _tcslen(source);
 
 if(m_szBuffer != NULL)
 {
  delete[] m_szBuffer;
  m_szBuffer = NULL;
 }

 AllocateMemory(nSourcelen + 1);
 memset(m_szBuffer, 0, (nSourcelen + 1));
 _tcscpy(m_szBuffer, source);

 return *this;
}

CStringUNI& CStringUNI::operator=(const CStringUNI& source)
{
 return operator=(source.m_szBuffer);
}

CStringUNI& CStringUNI::operator+=(const CStringUNI& source)
{
 size_t nSourceLen = _tcslen(source.m_szBuffer);
 size_t nBufferLen = _tcslen(m_szBuffer);

 TCHAR *pTempChar = new TCHAR[nSourceLen + nBufferLen + 1];
 _tcscpy(pTempChar, m_szBuffer);
 _tcscat(pTempChar, source.m_szBuffer);

 if(m_szBuffer != NULL)
 {
  delete []m_szBuffer;
  m_szBuffer = NULL;
 }

 m_szBuffer = pTempChar;
 
 return *this;
}

CStringUNI operator+(const CStringUNI& lhs, const CStringUNI& rhs)
{
 return CStringUNI(lhs) += rhs;
}

bool CStringUNI::operator ==(const TCHAR* source)const
{
 return (!_tcscmp(m_szBuffer, source));
}

bool CStringUNI::operator==(const CStringUNI& source) const
{
 return (!_tcscmp(source.m_szBuffer, m_szBuffer));
}

TCHAR CStringUNI::operator[](const size_t n)const
{
 return m_szBuffer[n];
}

TCHAR * CStringUNI::GetBuffer()const
{
 return m_szBuffer;
}

CStringUNI::~CStringUNI(void)
{
 if(m_szBuffer != NULL)
 {
  delete [] m_szBuffer;
  m_szBuffer = NULL;
 }
}
The following lines demonstrates the usage of this class.
// effString.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include "StringUNI.h"
#include &ltlocale.h&gt
#include &ltwindows.h&gt

int _tmain(int argc, _TCHAR* argv[])
{
 
 TCHAR *locale = _tsetlocale(LC_ALL, L"Japanese");
 CStringUNI objString(L"日本語がわかりません");

 CStringUNI objString1(L"日本語でなんと言いますか");

 objString += objString1;
 
 wprintf(L"%s\n", objString.GetBuffer());
 return 0;
}

In the above mentioned lines, I tried to create two different objects of type CStringUNI and then concatenated two objects and displayed the cancatenated string on the output window.
Once we run this program, after setting locale for the system to Japanese, we will get following output: -

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