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Janice Hobden

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XMLReader ReadSubTree always returns None

My XML looks like this:
<WHOLE_PAGE>
<CONSULTATION_PAGE SCREEN_NAME="Which Version">
<MESSAGE/>
<LEGEND/>
<QUESTION_ANSWER_GROUP QA_GROUP_ID="1">
<PROMPT/>
<QUESTION_ANSWER FIELD_NAME="which_version" OBJECT_NAME="Which_Version">
<QUESTION/>
<ANSWER STRING_LENGTH="" DISPLAY_LENGTH="5" DATA_TYPE="" ENTRY_MODE="Edit">1.00</ANSWER>
</QUESTION_ANSWER>
</QUESTION_ANSWER_GROUP>
</CONSULTATION_PAGE>

<CONSULTATION_PAGE SCREEN_NAME="Customer Info">
<MESSAGE/>
<LEGEND/>
<QUESTION_ANSWER_GROUP QA_GROUP_ID="1">
<PROMPT/>
<QUESTION_ANSWER FIELD_NAME="name" OBJECT_NAME="name">
<QUESTION/>
<ANSWER STRING_LENGTH="" DISPLAY_LENGTH="30" DATA_TYPE="" ENTRY_MODE="Edit">Fred</ANSWER>
</QUESTION_ANSWER>
</QUESTION_ANSWER_GROUP>

<QUESTION_ANSWER_GROUP QA_GROUP_ID="2">
<PROMPT/>
<QUESTION_ANSWER FIELD_NAME="surname" OBJECT_NAME="surname">
<QUESTION/>
<ANSWER STRING_LENGTH="" DISPLAY_LENGTH="30" DATA_TYPE="" ENTRY_MODE="Edit">Flintstone</ANSWER>
</QUESTION_ANSWER>
</QUESTION_ANSWER_GROUP>
</CONSULTATION_PAGE>

</WHOLE_PAGE>


What I'm trying to do is on reaching <CONSULTATION_PAGE> I want to create a new reader to read all the children of this element but it always returns NONE.  

This is my first time using XMLReader so its new to me... Can anyone point out the error in my code. Thanks

 static void Main(string[] args)
        {
            XmlReaderSettings settings = new XmlReaderSettings();
            settings.IgnoreWhitespace = true;
            XmlReader xmlReader = XmlReader.Create("C:/temp/Migration/XMLTEST_001.xml");
            while (xmlReader.Read())
            {              
                if (xmlReader.IsStartElement("CONSULTATION_PAGE"))                        
                {                                            
                    XmlReader pageNodes = xmlReader.ReadSubtree();                                                                        
                }
          }
     }

Thanks
Avatar of it_saige
it_saige
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Here is one way you could read the data.  Note this is definately not the best way but it should give you a general idea:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;

namespace EE_Q29009171
{
    class Program
    {
        static void Main(string[] args)
        {
            var document = XElement.Load("XMLFile1.xml");
            var pages = (from page in document.Descendants("CONSULTATION_PAGE")
                         select new
                         {
                             ScreenName = page.Attribute("SCREEN_NAME").Value,
                             Message = page.Element("MESSAGE").Value,
                             Legend = page.Element("LEGEND").Value,
                             QAGroup = new List<dynamic>(from qaGroup in page.Descendants("QUESTION_ANSWER_GROUP")
                                                         select new
                                                         {
                                                             ID = qaGroup.Attribute("QA_GROUP_ID").Value,
                                                             Prompt = qaGroup.Element("PROMPT").Value,
                                                             QA = new List<dynamic>(from qa in qaGroup.Descendants("QUESTION_ANSWER")
                                                                                    select new
                                                                                    {
                                                                                        FieldName = qa.Attribute("FIELD_NAME").Value,
                                                                                        ObjectName = qa.Attribute("OBJECT_NAME").Value,
                                                                                        Question = qa.Element("QUESTION").Value,
                                                                                        Answer = new
                                                                                        {
                                                                                            StringLength = qa.Element("ANSWER").Attribute("STRING_LENGTH").Value,
                                                                                            DisplayLength = qa.Element("ANSWER").Attribute("DISPLAY_LENGTH").Value,
                                                                                            DateType = qa.Element("ANSWER").Attribute("DATA_TYPE").Value,
                                                                                            EntryMode = qa.Element("ANSWER").Attribute("ENTRY_MODE").Value,
                                                                                            Value = qa.Element("ANSWER").Value
                                                                                        }
                                                                                    })
                                                         })
                         });

            foreach (var page in pages)
            {
                Console.WriteLine(page);
                foreach (var qaGroup in page.QAGroup)
                {
                    Console.WriteLine(qaGroup);
                    foreach (var qa in qaGroup.QA)
                    {
                        Console.WriteLine(qa);
                    }
                }
                Console.WriteLine();
            }
            Console.ReadLine();
        }
    }
}

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Produces the following output -User generated image
-saige-
Avatar of Janice Hobden
Janice Hobden

ASKER

Hi, thanks for your feedback.  I actually already have another solution that uses xml document and does read all the elements that I need and processes them (I am migrating xml into a sql table so need very specific parts of the xml), but it's just too slow using standard xml parsing.  I read that XMLReader is much quicker which is why I am now trying this route.  At present it looks like my current method will run for 12 hours as I have so many thousands of xml files to migrate, so performance is the key issue. I'm hoping if I resolve this to cut this down to maybe just an hour or two. But I appreciate your time and speedy response.
ASKER CERTIFIED SOLUTION
Avatar of it_saige
it_saige
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Thank you so much, I am going to try that in my code.  I really do appreciate your assistance.
No comment has been added to this question in more than 21 days, so it is now classified as abandoned.

I have recommended this question be closed as follows:

Accept: it_saige (https:#a42049257)

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