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──Microsoft Foundation Classes──────────────────────────────────────────────
 
  Argument-Passing Conventions
 
  When you define a class interface, you must determine the
  argument-passing convention for your member functions. There are some
  standard rules for passing and returning CString objects. If you follow
  these rules, you will have efficient, correct code.
 
  Strings as Function Inputs
 
  If a string is an input to a function, in most cases it is best to
  declare the string function parameter as const char*. Convert to CString
  object as necessary within the function, using constructors and
  assignment operators. If the string contents are to be changed by a
  function, declare the parameter as a nonconstant CString reference
  (CString&).
 
  Strings as Function Outputs
 
  Normally you can return CString objects from functions since CStrings
  follow value semantics like primitive types. To return a read-only
  string, use a constant CString reference (const CString&).
 
  Example
 
  class CName : public CObject
  {
  private:
      CString m_firstName;
      char m_middleInit;
      CString m_lastName;
  public:
      CName() {}
      void SetData( const char* fn, const char mi, const char* ln )
      {
          m_firstName = fn;
          m_middleInit = mi;
          m_lastName = ln;
      }
      void GetData( CString& cfn, char mi, CString& cln )
      {
          cfn = m_firstName;
          mi = m_middleInit;
          cln = m_lastName;
      }
      CString GetLastName()
      {
          return m_lastName;
      }
  };
 
      CName name;
      CString last, first;
      char middle;
 
      name.SetData( "John", 'Q', "Public" );
      ASSERT( name.GetLastName() == "Public" );
      name.GetData( first, middle, last );
      ASSERT( ( first == "John" ) && ( last == "Public" ) );
  }
  return 0;
  }
 
 
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