Question

I’m using XmlSerializer to deserialize Xml achives. But I found the class xsd.exe generated only offers capability to read the xml, but no validation. For example, if one node is missing in a document, the attribute field of the generated class will be null, rather than throws a validation exception as I expected. How can I achieve that? Thanks!

Answer 1

The following code should validate against a schema while deserializing. Similar code can be used to validate against a schema while serializing.

private static Response DeserializeAndValidate(string tempFileName)
{
    XmlSchemaSet schemas = new XmlSchemaSet();
    schemas.Add(LoadSchema());

    Exception firstException = null;

    var settings = new XmlReaderSettings
                   {
                       Schemas = schemas,
                       ValidationType = ValidationType.Schema,
                       ValidationFlags =
                           XmlSchemaValidationFlags.ProcessIdentityConstraints |
                           XmlSchemaValidationFlags.ReportValidationWarnings
                   };
    settings.ValidationEventHandler +=
        delegate(object sender, ValidationEventArgs args)
        {
            if (args.Severity == XmlSeverityType.Warning)
            {
                Console.WriteLine(args.Message);
            }
            else
            {
                if (firstException == null)
                {
                    firstException = args.Exception;
                }

                Console.WriteLine(args.Exception.ToString());
            }
        };

    Response result;
    using (var input = new StreamReader(tempFileName))
    {
        using (XmlReader reader = XmlReader.Create(input, settings))
        {
            XmlSerializer ser = new XmlSerializer(typeof (Response));
            result = (Response) ser.Deserialize(reader);
        }
    }

    if (firstException != null)
    {
        throw firstException;
    }

    return result;
}