Trouble with XML Deserialization into XSD generated classes

Question

I have a rather detailed xml file. Below is the top level nodes (I have included the ellipse as the lower level nodes are all well formed and properly filled with data):

<?xml version="1.0" encoding="UTF-8"?>
<config>
    <Models>...</Models>
    <Data>...</Data>
</config>

I have created an xsd file from using the Visual Studio 2008 command prompt:

xsd sample.xml

This generates the xsd file just fine. I then auto generate classes from the xsd with the command:

xsd sample.xsd /classes

For the deserialization of the xml file into a class object, I'm using the read function in the helper class:

public class XmlSerializerHelper<T>
{
    public Type _type;

    public XmlSerializerHelper()
    {
        _type = typeof(T);
    }

    public void Save(string path, object obj)
    {
        using (TextWriter textWriter = new StreamWriter(path))
        {
            XmlSerializer serializer = new XmlSerializer(_type);
            serializer.Serialize(textWriter, obj);
        }
    }

    public T Read(string path)
    {
        T result;
        using (TextReader textReader = new StreamReader(path))
        {
            XmlSerializer deserializer = new XmlSerializer(_type);
            result = (T)deserializer.Deserialize(textReader);
        }
        return result;
    }
}

When attempting the deserialization with:

var helper = new XmlSerializerHelper<configModels>();
var obj = new configModels();
obj = helper.Read(filepath);

I receive an error that I have deduced is because the deserializer is looking for the 'Models' node but the corresponding class name was generated as a combination of the root node and the 'Model' node (configModels). Why are the class names generated like this?

I tried to deserialize from the top node using:

var helper = new XmlSerializerHelper<config>();
var obj = new config();
obj = helper.Read(filepath);

Unfortunately, this the results in a slew of errors like the following:

System.InvalidOperationException was unhandled by user code
Message="Unable to generate a temporary class (result=1).
error CS0030: Cannot convert type 'Application.Lease[]' to 'Application.Lease'
error CS0030: Cannot convert type 'Application.CashFlow[]' to 'Application.CashFlow'
...ect.

Can somebody steer me towards what I might be doing wrong with my xsd auto-generating?

Answer 1

XSD.EXE is a good start - but it's far from perfect. Also, based on the XML you provided, XSD.EXE can't always decide for sure whether something is a single instance of an object, or an open-ended array of objects.

This seems to be the case for your two elements - Application.Lease and Application.CashFlow. How are they defined in the generated XSD file? Does that make sense to you? Quite possibly, you'd have to add a little hints, such as:

<xs:element name="Lease" minOccurs="0" maxOccurs="1" />

for an optional property, that's zero or one occurences only. Things like that are really hard for the xsd.exe tool to figure out based on just a single XML sample file.

Marc