Writing XML SAX Parsers in C#

Environment: C#

This project gives you a head start on writing XML parsers in C#. The important namespace to achieve our goal would be System.Xml. Though you might find it strange, unlike other languages/class libraries, there are no direct functions such as startElement and endElement at your disposal, or to come to your rescue. You will have to manage this on your own. So, let's look at this important block of code.

void ParseURL(string strUrl)
{
  try
  {
    XmlTextReader reader = new XmlTextReader(strUrl);
    while (reader.Read())
    {
      switch (reader.NodeType)
      {
        case XmlNodeType.Element:
           Hashtable attributes = new Hashtable();
           string strURI= reader.NamespaceURI;
           string strName= reader.Name;
           if (reader.HasAttributes)
           {
             for (int i = 0; i < reader.AttributeCount; i++)
             {
                reader.MoveToAttribute(i);
                attributes.Add(reader.Name,reader.Value);
             }
           }
           StartElement(strURI,strName,strName,attributes);
        break;
        //
        //you can handle other cases here
        //
        //case XmlNodeType.EndElement:
        // Todo
        //case XmlNodeType.Text:
        // Todo
        default:
        break;
      }
    }
  }
  catch (XmlException e)
  {
    Console.WriteLine("error occured: " + e.Message);
  }
}

As you can see, the main class here is XmlTextReader. XmlTextReader provides forward-only, read-only access to a stream of XML data. The current node refers to the node on which the reader is positioned. The reader is advanced by using any of the read methods and properties that reflect the value of the current node. Note that we cache the element name before we move to the attributes.

The NodeType property of XmlTextReader gets the type of the current node. Accordingly, we process the node and call necessary functions on it.

You can forward me your comments at lparam@hotmail.com.



Comments

Leave a Comment
  • Your email address will not be published. All fields are required.

Top White Papers and Webcasts

  • With the mobility trend in full swing, most organizations today are already vulnerable to potential security risks. The security basics of yesterday--policy, encryption, and authentication--no longer cover fundamental security needs. Businesses must act quickly to get the most from mobility while effectively protecting information and systems.  This white paper describes the challenges IT faces, from mobilizing business processes to protecting corporate data, and outlines the five must-haves for an enterprise …

  • Finance leaders have been talking about expanding the value-added role of their teams for a long time. The debate is no longer whether the finance and accounting function needs to become a more strategic partner to the rest of the business but rather how to get there. Technology innovation has caught up to this ambition, and what was once aspiration can be a reality – and the choice is now yours. Read this research report to learn how to make the most of information tools to enable innovation and growth.

Most Popular Programming Stories

More for Developers

RSS Feeds

Thanks for your registration, follow us on our social networks to keep up-to-date