Question

I am using the .NET XmlSerializer class to deserialize GPX files.

There are two versions of the GPX standard:

• <gpx xmlns=”http://www.topografix.com/GPX/1/0″&gt; … </gpx>
• <gpx xmlns=”http://www.topografix.com/GPX/1/1″&gt; … </gpx>

Also, some GPX files do not specify a default namespace:

• <gpx> … </gpx>

My code needs to handle all three cases, but I can’t work out how to get XmlSerializer to do it.

I am sure there must be a simple solution because this a common scenario, for example KML has the same issue.

Answer 1

Here’s the solution I came up with before the other suggestions came through:

  var settings = new XmlReaderSettings();
  settings.IgnoreComments = true;
  settings.IgnoreProcessingInstructions = true;
  settings.IgnoreWhitespace = true;
  using (var reader = XmlReader.Create(filePath, settings))
  {
    if (reader.IsStartElement("gpx"))
    {
      string defaultNamespace = reader["xmlns"];
      XmlSerializer serializer = new XmlSerializer(typeof(Gpx), defaultNamespace);
      gpx = (Gpx)serializer.Deserialize(reader);
    }
  }

This example accepts any namespace, but you could easily make it filter for a specific list of known namespaces.