Reading number of elements of a XML using XMLReader

09-05-2008 10:45 AM |

 Hi all, I think this is a pretty easy one.

Let's say I have this XML named "datafile.xml":

<bookstore>
  <book genre="autobiography" publicationdate="1981-03-22" ISBN="1-861003-11-0">
    ![CDATA[The Autobiography of Benjamin Franklin]]>
  </book>
  <book genre="Literary" publicationdate="1995-12-01" ISBN="1-845269-25-5">
    ![CDATA["Gone with the Wind"]]>
  </book>
  <book genre="Business and Economics" publicationdate="2006-05-25" ISBN="1-452367-96-6">
    ![CDATA["Business Law Text and Cases"]]>
  </book>
</bookstore> 

  I'm using XMLReader to parse it.

StringBuilder output = new StringBuilder();
XmlReaderSettings settings = new XmlReaderSettings();
settings.XmlResolver = new XmlXapResolver();
XmlReader reader = XmlReader.Create("datafile.xml");
reader.ReadToFollowing("book");
string title = reader.ReadElementContentAsString();
string book = reader.value;
output.Append(title);
reader.Close();
OutputTextBlock.Text = output.ToString();

My question is, how can I read the number of elements in the XML, in this case "book"? it should be 3. I've tried validating it using HasValue, but it does not work.

Thanks a lot! 

 

Re: Reading number of elements of a XML using XMLReader

09-05-2008 10:57 AM |

Using LINQ To XML

 

XDocument doc = XDocument.Load("datafile.xml");

var res = (from n in doc.Descendants("book")
           select n).Count();

  

Re: Reading number of elements of a XML using XMLReader

09-05-2008 11:34 AM |

Hi,

Thanks a lot, it worked, but I definitely would like to keep using XMLReader, isn't there any other way it can be solved using it?

Re: Reading number of elements of a XML using XMLReader

09-05-2008 12:21 PM |

I concur with Skyrunner, it is better to use LINQ; it is much more powerful and elegant. If you have a learning curve to climb regarding parsing or generating XML I think its best to spend your time researching LINQ. But just for the record here is how to count your books using a reader:

            int count = 0;

            while (reader.Read())
            {
                if (reader.NodeType == XmlNodeType.Element && reader.Name.Equals("book"))
                {
                    count++;
                }
            }

 

The SDK documentation for the XmlReader class has a simple example that basically shows you all you need to know about it.