Custom serialization using DataContractSerializer

Question

I am having a look into using the DataContractSerializer and I'm having trouble getting the right output format. The DataContractSerializer serializes the following class

[DataContract(Name = "response")]
public class MyCollection<T> 
{
    [DataMember]
    public List<T> entry { get; set; }
    [DataMember]
    public int index { get; set; }
}

Into

<response><entry><T1>object1</T1><T2>object2</T2></entry><index></index></response>

But what I want is

<response><entry><T1>object1</T1></entry><entry><T2>object2</T2></entry><index></index></response>

How do I do this with the DataContractSerializer? But also maintain the first output for DataContractJsonSerializer?

Answer 1

If you are writing xml, I wonder whether xml serializer wouldn't be a better choice (it has more granular control over the names, etc).

The problem, though, is that XmlSerializer isn't always the biggest fan of generics...

Additionally - having tried a few options involving [XmlArray] / [XmlArrayItem] etc... it looks very hard to get it to the format you want... plus it isn't easy to guess what you mean by the T1 / T2 - but the following may come close:

[XmlRoot("response")]
public class MyResponse : MyCollection<int> { }

[DataContract(Name = "response")]
public class MyCollection<T>
{
    [DataMember]
    [XmlElement("entry")]
    public List<T> entry { get; set; }
    [DataMember]
    public int index { get; set; }
}

This has both XmlSerializer and DataContractSerializer attributes, but I had to lose the generics in the type we use for the response (hence the "closed" MyResponse type)

Answer 2

Hi,

Based on this article, it seems that DataContractSerializer does not have support for customizing the resultant xml.

http://www.danrigsby.com/blog/index.php/2008/03/07/xmlserializer-vs-datacontractserializer-serialization-in-wcf/

From the MS site there is an important note: 'The DataContractAttribute attribute should not be applied to classes that already implement the ISerializable interface or that are marked with the SerializableAttribute. An exception is thrown if you try to serialize an instance of such a type.'

PS: Sorry I couldn't post the second link, but the engine does not allow post more than one link to new users.

Regards, Herberth