FXCop / Code Analysis on WCF DataContract Classes with Array - Creates CA1819 Error

Question

I have the following WCF data contract class:

[DataContract]
public class BinaryResponse : ResponseBase
{
    [DataMember]
    public byte[] Payload { get; set; }
}

Nice and simple, works exactly as I need it to. However I am now running this through the full code analysis ruleset. This generates the following warning:

CA1819 : Microsoft.Performance : Change 'BinaryResponse.Payload' to return a collection or make it a method.

Having looked at the help page for this error the solution is a simple one. However the solution doesn't really fit with WCF datamembers.

So the question is, how can I refactor this class to still be useable as a WCF datacontract and also pass the code analysis?

Cheers

Answer 1

You can do change the byte array to an enumerable or collection, like tehe following:

[DataContract]
public class BinaryResponse : ResponseBase
{
    [DataMember] public ICollection<byte> Payload { get; set; }
}

or you can keep the byte[] attribute in a private array and wrap it in an ICollection property (if you need the internal array):

[DataContract]
public class BinaryResponse : ResponseBase
{
    // this is NOT a member of the DataContract
    private byte[] payload;

    [DataMember] public ICollection<byte> Payload {
        get { return this.payload; }
        set { this.payload = value.toArray(); }
    }
}