Deserializing XML returns null for collection property

Question

I'm trying to deserialize the following XML:

<?xml version="1.0" encoding="utf-8" ?> 
<mf:somedata xmlns:mf="urn:somedata">
    <CurrentAccount>
        <AccountType>test</AccountType>
        <Charge>
            <ChargeType>test</ChargeType>
        </Charge>
    </CurrentAccount>
    <CurrentAccount>
        <AccountType>test 2</AccountType>
        <Charge>
            <ChargeType>test 2</ChargeType>
        </Charge>
    </CurrentAccount>
</mf:somedata>

Using the following classes:

[XmlRoot("somedata", Namespace = "urn:somedata")]
public class MfCurrentAccounts
{
    [XmlElement("CurrentAccount")]
    public CurrentAccount[] CurrentAccounts { get; set; }
}

public class CurrentAccount
{
    public string AccountType { get; set; }

    [XmlElement("Charge")]
    public Charge[] Charges { get; set; }
}

public class Charge
{
    public string ChargeType { get; set; }
}

var c = new XmlSerializer(typeof(MfCurrentAccounts)).Deserialize(new StringReader(xml)) as MfCurrentAccounts;

c.CurrentAccounts // <-- is always null

But no matter what I try, the CurrentAccounts array is null when I deserialize it. I've tried every combination I can think of with the attributes (I've tried XmlArray and XmlArrayItem too).

What am I doing wrong? :S

Answer 1

The issue is with Namespaces.

When I created that entire class setup in a test situation, i got a very different looking output. here is what I think you should be trying to read in:

    <?xml version="1.0"?>
    <mf:somedata xmlns:mf="urn:somedata">
        <mf:CurrentAccount>
            <mf:AccountType>something 1</mf:AccountType>
            <mf:Charge>
                <mf:ChargeType>Charge Type 1</mf:ChargeType>
            </mf:Charge>
        </mf:CurrentAccount>
        <mf:CurrentAccount>
            <mf:AccountType>something 2</mf:AccountType>
            <mf:Charge>
                <mf:ChargeType>Charge Type 2</mf:ChargeType>
            </mf:Charge>
        </mf:CurrentAccount>
    </mf:somedata>

Notice all the extra mf:. When you declare the namespace, the serializer will work with that and only de-serialize nodes that properly belong to that namespace. You either need to get rid of it entirely or fix your input appropriately. Here is the code that I used to generate that output note: the class definitions are completely unchanged

XmlSerializer ser = new XmlSerializer(typeof(MfCurrentAccounts));
XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
ns.Add("mf", "urn:somedata");

MemoryStream ms = new MemoryStream();
ser.Serialize(ms, a, ns);

and when reading it back in:

ms.Position = 0;
b = ser.Deserialize(ms) as MfCurrentAccounts;

after running both sections, b is now a perfect clone of a, and the xml I showed above is the generated xml.