String Parser Class with Field Validation and Exception Handling

Download demo project - 21.7 Kb

Sample Image - CStringParserEx.png

Introduction

In scientific programming we encounter data files, containing textual records as entry, and so we need to split and check them. A few months ago, I read Remon's article, it's a good base for my work. I derived a class from CStringParser and added two additional classes (CFieldAM and CStringParserExceptAM) to it and every thing goes well with them.

  CStringParserAM parser_engine;
  CString example_string(_T("Ali Khanlarkhani alikhus@yahoo.com 1234"));
  int         count;
  CString         first_name, last_name, e_mail;
  int         id;

  parser_engine.Reset();

  parser_engine.AddField(_T("First Name"), CFieldAM::FT_BSTR, _T(""));
  parser_engine.AddField(_T("Last Name"),  CFieldAM::FT_BSTR, _T(""));
  parser_engine.AddField(_T("E-mail"), <BR>    CFieldAM::FT_BSTR, _T(""), _T(""), _T("\\w+@\\w+\\.\\w+"));
  parser_engine.AddField(_T("ID"), CFieldAM::FT_INT,  _T(""));
        
  try{

     parser_engine.ParserEx((LPCTSTR) example_string, poCmdLine, count);

     parser_engine.Field(0).Value(&first_name);
     parser_engine.Field(1).Value(&last_name);
     parser_engine.Field(2).Value(&e_mail);
     parser_engine.Field(3).Value(&id);

  } /// try
  catch(CStringParserExceptAM& e){

     TCHAR  error_message[1024];
     e.GetErrorMessage(error_message, 1024);
     MessageBox(error_message);

  } /// catch(CStringParserExceptAM& e)

Usage

CFieldAM uses Regex++, thus you need to download and install it. (see Perlmunger's article for details.)
Add CStringParser(.cpp and .h), CStringParserAM(.cpp and .h), CFieldAM(.cpp and .h) to your project.
Declare an instance of CStringParserAM, and use AddField method to add each field to it.
Call ParserEx with source string.

Conclusion

See demo project for details. If you find it useful I will prepare a complete documentation as soon as possible. Demo project is not too hard for understanding. Enjoy.