How to Save a DataRow to XML

• Download demo project - 14.5 KB
• Download source - 18.7 KB

Introduction

Just recently, I had the need to save the contents of a DataRow as XML data for further processing. I looked at all the properties and methods that could be used, but nothing worked.

I couldn't find any really good solution for my problem in the different coding forums either, so I came up with my own solution.

Hopefully, it can help someone else.

Note: When running the demo, make sure to select a row in the Parent table by clicking on the row header.

Background

In this case, I have created a DataSet with DataTables named Parent, Child and GrandChild. The parent table is presented in three DataGridViews where a user can select one table and then convert that DataTable to XML.

Using the Code

I have an example DataSet that looks like this:

Fill the dataset with some sample data.

DataSetExample.ParentRow parent = null;
DataSetExample.ChildRow child = null;

parent = dataSetExample.Parent.AddParentRow("Object");
child = dataSetExample.Child.AddChildRow(parent, "XmlNode");
dataSetExample.GrandChild.AddGrandChildRow(child, "XmlLinkedNode");
dataSetExample.GrandChild.AddGrandChildRow(child, "XmlDocument");

child = dataSetExample.Child.AddChildRow(parent, "Encoding");
dataSetExample.GrandChild.AddGrandChildRow(child, "ASCIIEncoding");
dataSetExample.GrandChild.AddGrandChildRow(child, "UnicodeEncoding");
dataSetExample.GrandChild.AddGrandChildRow(child, "UTF32Encoding");

parent = dataSetExample.Parent.AddParentRow("XmlLinkedNode");
child = dataSetExample.Child.AddChildRow(parent, "XmlCharacterData");
dataSetExample.GrandChild.AddGrandChildRow(child, "XmlComment");

parent = dataSetExample.Parent.AddParentRow("LocalFileSettingsProvider");
child = dataSetExample.Child.AddChildRow(parent, "ClientSettingsProvider");
dataSetExample.GrandChild.AddGrandChildRow(child, "ProfileProvider");

The code below is inside a user triggered event.

In here, I want to get all XML data for a DataTable with a specific name. In this case, I want it as a string.

private void buttonGetXML_Click(object sender, EventArgs e)
{
  // Only one row can be selected
  if (dgParents.SelectedRows.Count == 1)
  {
    DataGridViewRow dgv = dgParents.SelectedRows[0];
    DataRowView drv = (dgv.DataBoundItem as DataRowView);
    if (drv != null)
    {
      DataSetExample.ParentRow parentRow = (drv.Row as DataSetExample.ParentRow);
      if (parentRow != null)
      {
        string xmlData = "";
        // Write all data in the dataset to a string
        using (MemoryStream ms = new MemoryStream())
        {
          parentRow.Table.WriteXml(ms);
          byte[] data = ms.ToArray();
          xmlData = ASCIIEncoding.ASCII.GetString(data);
        }
        
        // Load the XML string into an XDocument
        XDocument xdoc = XDocument.Parse(xmlData);

        // Get the top node
        XName xnDataSet = XName.Get(parentRow.Table.DataSet.DataSetName, parentRow.Table.DataSet.Namespace);
        XElement xeDataSet = xdoc.Element(xnDataSet);

        // Find the Parent in the complete XML data that matches the attribute name.
        // E.g. ParentName = Object;
        XName xnParent = XName.Get("Parent", parentRow.Table.DataSet.Namespace);
        XName xnParentName = XName.Get("ParentName", parentRow.Table.DataSet.Namespace);
        XElement xeParent = xeDataSet.Elements(xnParent).
            Where(x => x.Element(xnParentName).Value == parentRow.ParentName).
            FirstOrDefault();

        // Now show the XML in a RichTextBox
        richTextBox.Text = xeParent.ToString();
      }
    }
  }
}

Points of Interest

I am not entirely happy with my solution. There should be an easier way.

Maybe someone else out there has done something in this area worth posting.

History

1. First release
2. Simplified the code and updated with a complete demo