XML deserialization of different classes in file

Question

I get a file with different content (currently 4 different classes), either

<ClassA><!-- content --></ClassA>

or

<ClassB><!-- content --></ClassB>

or ...

At time of parsing I have no further information which class is in the file.

So, currently, I try to parse by trial and error:

try
{
  ClassA result = (ClassA)new XmlSerializer(typeof(ClassA)).Deserialize(reader);
  if(!(result is null)) { \\do something }
}
catch (Exception) {}

And the same for ClassB and so on ...

Is there a more elegant way to parse the classes?

I can give all classes the same base class, although the are quite different in their form.

Brute force? Read the first line and look for the appropriate name? It's kludge and horribly inelegant, but it might solve your problem — Flydog57, May 18 '21 at 18:03
Inherit your classes from a common ancestor. Use the XmlIncludeAttribute. — Alexander Petrov, May 18 '21 at 18:44
You could use `XmlSerializer.CanDeserialize(XmlReader)` to check to see whether a given serializer is able to deserialize a given root element. See [How to deserialize XML if the return type could be an Error or Success object](https://stackoverflow.com/q/44234061/3744182). — dbc, May 19 '21 at 04:29
And additional options to be found at [How to do a polymorphic deserialization in C# given a XSD?](https://stackoverflow.com/q/28086893/3744182). — dbc, May 19 '21 at 14:39

score 0 · Answer 1 · answered Jun 15 '21 at 13:13

I solved this issue with XmlSerializer.CanDeserialize(XmlReader)

            using (var reader = XmlReader.Create(stream))
            {
                foreach (var type in types)
                {
                    var serializer = new XmlSerializer(type);
                    if (serializer.CanDeserialize(reader))
                    {
                        return serializer.Deserialize(reader);
                    }
                }
                throw new XmlException("Invalid xml type");
            }

XML deserialization of different classes in file

1 Answers1