Comparing two XML files & generating a third with XMLDiff in C#

Question

I am trying to write a simple algorithm to read two XML files with the exact same nodes and structure but not necessarily the same data inside the child nodes and not the sa

Answer 1

Okay... I finally opted with a pure C# solution to compare the two XML files, without using the XML Diff/Patch .dll and without even needing to use XSL transforms. I will be needing XSL transforms in the next step though, to convert the Xml into HTML for viewing purposes, but I have figured an algorithm using nothing but System.Xml and System.Xml.XPath.

Here is my algorithm:

private void CompareXml(string file1, string file2)
{
    // Load the documents
    XmlDocument docXml1 = new XmlDocument();
    docXml1.Load(file1);
    XmlDocument docXml2 = new XmlDocument();
    docXml2.Load(file2);


    // Get a list of all player nodes
    XmlNodeList nodes1 = docXml1.SelectNodes("/Stats/Player");
    XmlNodeList nodes2 = docXml2.SelectNodes("/Stats/Player");

    // Define a single node
    XmlNode node1;
    XmlNode node2;

    // Get the root Xml element
    XmlElement root1 = docXml1.DocumentElement;
    XmlElement root2 = docXml2.DocumentElement;

    // Get a list of all player names
    XmlNodeList nameList1 = root1.GetElementsByTagName("Name");
    XmlNodeList nameList2 = root2.GetElementsByTagName("Name");

    // Get a list of all teams
    XmlNodeList teamList1 = root1.GetElementsByTagName("Team");
    XmlNodeList teamList2 = root2.GetElementsByTagName("Team");

    // Create an XmlWriterSettings object with the correct options. 
    XmlWriter writer = null;
    XmlWriterSettings settings = new XmlWriterSettings();
    settings.Indent = true;
    settings.IndentChars = ("  ");
    settings.OmitXmlDeclaration = false;

    // Create the XmlWriter object and write some content.
    writer = XmlWriter.Create(StatsFile.XmlDiffFilename, settings);
    writer.WriteStartElement("StatsDiff");


    // The compare algorithm
    bool match = false;
    int j = 0;

    try 
    {
        // the list has 500 players
        for (int i = 0; i < 500; i++)
        {
            while (j < 500 && match == false)
            {
                // There is a match if the player name and team are the same in both lists
                if (nameList1.Item(i).InnerText == nameList2.Item(j).InnerText)
                {
                    if (teamList1.Item(i).InnerText == teamList2.Item(j).InnerText)
                    {
                        match = true;
                        node1 = nodes1.Item(i);
                        node2 = nodes2.Item(j);
                        // Call to the calculator and Xml writer
                        this.CalculateDifferential(node1, node2, writer);
                        j = 0;
                    }
                }
                else
                {
                    j++;
                }
            }
            match = false;

        }
        // end Xml document
        writer.WriteEndElement();
        writer.Flush();
    }
    finally
    {
        if (writer != null)
            writer.Close();
    }
}

XML Results:

    
  
    Sidney Crosby
    PIT
    C
    0
    0
    0
    0
    0
    0
    0
    0
    0
    0
    0
    0
    0
    0
  

  
    Steven Stamkos
    TBL
    C
    1
    0
    0
    0
    0
    2
    0
    0
    0
    0
    4
    -0,6000004
    -0,09999847
    0,09999847
  
[...]

I have spared to show the implementation for the CalculateDifferential() method, it is rather cryptic but it is fast and efficient. This way I could obtain the results wanted without using any other reference but the strict minimum, without having to use XSL...