Namespace for [DataContract]

Question

I can't find the namespace to use for [DataContract] and [DataMember] elements. According to what I've found, it seems that adding the following should be enough, but in my case it is not.

using System;
using System.Runtime.Serialization;

Here is a snippet of my code:

using System;
using System.Runtime.Serialization;

namespace MyNamespace {

    [DataContract]
    public class Tuple<T1, T2> {
            // A custom implementation of a Tuple
            //...
            //...
        }
}

And the error I get:

The type or namespace name 'DataContract' could not be found (are you missing a using directive or an assembly reference?)

Am I not using the right namespaces?

Adena

Using VS 2017, compiler error, can't build, no message in errors list or any indication at all. No syntax coloring of DataContract, nothing. – Lach

@Lach Right click on your project Add/Reference. In the dialog find System.Runtime.Serialization and make checkbox cheked state. Then Press "Ok" – Cud

Answer 1

DataContractAttribute Class is in the System.Runtime.Serialization namespace.

You should add a reference to System.Runtime.Serialization.dll. That assembly isn't referenced by default though. To add the reference to your project you have to go to References -> Add Reference in the Solution Explorer and add an assembly reference manually.

Campy

....and that assembly isn't referenced by default, so you have to go to References -> Add Reference in Solution Explorer and add an assembly reference... – Coniferous

That's it, I didn't have the reference in my solution! I thought that if a reference were needed, it would get me an error on the line using System.Runtime.Serialization;. I guess I was wrong :) – Adena

Ugh. Why on Earth doesn't it error on the using statement? That seems to make sense to me. – Freyah

I guess that's because another dll is using that namespace (otherwise you would get an error) – Alluvial

Thank you! None of Microsoft's example doc mentions this. – Survive

If you are using VisualStudio you'll need to exit VS and reopen it before it will recognize newly referenced packages. – Advowson

Answer 2

http://msdn.microsoft.com/en-us/library/system.runtime.serialization.datacontractattribute.aspx

DataContractAttribute is in System.Runtime.Serialization namespace and you should reference System.Runtime.Serialization.dll. It's only available in .Net >= 3

Zurn

Answer 3

In visual studio for .Net 4.0 framework,

1. Try to add new reference to project.
2. On .Net Tab, Search System.Runtime.Serialization.
3. Now, you can use using System.Runtime.Serialization. And the error will not be shown.

Yarak

Answer 4

[DataContract] and [DataMember] attribute are found in System.ServiceModel namespace which is in System.ServiceModel.dll .

System.ServiceModel uses the System and System.Runtime.Serialization namespaces to serialize the datamembers.

Gynaeco

Answer 5

I solved this problem by adding C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.0\System.Runtime.Serialization.dll in the reference

Whit

Answer 6

First, I add the references to my Model, then I use them in my code. There are two references you should add:

using System.ServiceModel;
using System.Runtime.Serialization;

then, this problem was solved in my program. I hope this answer can help you. Thanks.

Gook