In WCF, can data contract classes inherit from one another?

Answer:

[DataContract]
public class A
{
[DataMember]
public MyCustomType AValue1{ get; set; }

[DataMember]
public MyCustomType AValue2 { get; set; }
}

[DataContract]
public class B: A
{
[DataMember]
public double BValue1{ get; set; }

[DataMember]
public double BValue2 { get; set; }
}

the metadata fails to load when testing the services.
What needs to be done to load both super and sub class.
We must add KnownType Attribute.

[DataContract]
[KnownType(typeof(B))]
public class A
{
[DataMember]
public string Value { get; set; }
}

[DataContract]
public class B : A
{
[DataMember]
public string OtherValue { get; set; }
}