Data Contract Serialization Not Working For All Elements

Question

I have an XML file that I'm trying to serialize into an object. Some elements are being ignored.

My XML File:

<?xml version="1.0" encoding="utf-8" ?> 
<License xmlns="http://schemas.datacontract.org/2004/07/MyApp.Domain"&gt;
<Guid>7FF07F74-CD5F-4369-8FC7-9BF50274A8E8</Guid> 
<Url>http://www.gmail.com&lt;/Url&gt; 
<ValidKey>true</ValidKey> 
<CurrentDate>3/1/2010 9:39:28 PM</CurrentDate> 
<RegistrationDate>3/8/2010 9:39:28 PM</RegistrationDate> 
<ExpirationDate>3/8/2099 9:39:28 PM</ExpirationDate> 
</License>

My class definition:

[DataContract]
public class License
{
    [DataMember]
    public virtual int Id { get; set; }
    [DataMember]
    public virtual string Guid { get; set; }
    [DataMember]
    public virtual string ValidKey { get; set; }
    [DataMember]
    public virtual string Url { get; set; }
    [DataMember]
    public virtual string CurrentDate { get; set; }
    [DataMember]
    public virtual string RegistrationDate { get; set; }
    [DataMember]
    public virtual string ExpirationDate { get; set; }
}

And my Serialization attempt:

XmlDocument Xmldoc = new XmlDocument();
Xmldoc.Load(string.Format(url));

string xml = Xmldoc.InnerXml;
var serializer = new DataContractSerializer(typeof(License));
var memoryStream = new MemoryStream(Encoding.UTF8.GetBytes(xml));
License license = (License)serializer.ReadObject(memoryStream);
memoryStream.Close();

The following elements are serialized:

• Guid
• ValidKey

The following elements are not serialized:

• Url
• CurrentDate
• RegistrationDate
• ExpirationDate

Replacing the string dates in the xml file with "blah" doesn't work either. What gives?

Answer 1

DataContractSerializer requires the XML elements representing properties to be in alphabetical order. So, your XML should be:

<?xml version="1.0" encoding="utf-8" ?> 
<License xmlns="http://schemas.datacontract.org/2004/07/MyApp.Domain"&gt;
    <CurrentDate>3/1/2010 9:39:28 PM</CurrentDate> 
    <ExpirationDate>3/8/2099 9:39:28 PM</ExpirationDate> 
    <Guid>7FF07F74-CD5F-4369-8FC7-9BF50274A8E8</Guid> 
    <RegistrationDate>3/8/2010 9:39:28 PM</RegistrationDate> 
    <Url>http://www.gmail.com&lt;/Url&gt; 
    <ValidKey>true</ValidKey> 
</License>

The exception, as John pointed out, is if you are using the Order property on your DataMember attributes. In that case, the XML elements must be in the specified order.