Method QueryStringValue

samples/Windows/WTL/atlapp.h:1911–1947

	}

	LONG QueryStringValue(LPCTSTR pszValueName, LPTSTR pszValue, ULONG* pnChars)
	{
		ATLASSERT(m_hKey != NULL);
		ATLASSERT(pnChars != NULL);

		ULONG nBytes = (*pnChars) * sizeof(TCHAR);
		DWORD dwType = 0;
		*pnChars = 0;
		LONG lRes = ::RegQueryValueEx(m_hKey, pszValueName, NULL, &dwType, reinterpret_cast<LPBYTE>(pszValue), &nBytes);
	
		if (lRes != ERROR_SUCCESS)
		{
			return lRes;
		}

		if(dwType != REG_SZ && dwType != REG_EXPAND_SZ)
		{
			return ERROR_INVALID_DATA;
		}

		if (pszValue != NULL)
		{
			if(nBytes != 0)
			{
				if ((nBytes % sizeof(TCHAR) != 0) || (pszValue[nBytes / sizeof(TCHAR) -1] != 0))
					return ERROR_INVALID_DATA;
			}
			else
			{
				pszValue[0] = _T('\0');
			}
		}

		*pnChars = nBytes / sizeof(TCHAR);

		return ERROR_SUCCESS;
	}

	LONG QueryMultiStringValue(LPCTSTR pszValueName, LPTSTR pszValue, ULONG* pnChars)
	{