Question

Trying to implement a domain service in a SL app and getting the following error:

Parameter ‘spFolderCreate’ of domain method ‘CreateSharePointFolder’ must be an entity type exposed by the DomainService.

 [EnableClientAccess()]
public class FileUploadService : DomainService
{
    public void CreateSharePointFolder(SharePointFolderCreate spFolderCreate)
    {
        SharePointFolder spf = new SharePointFolder();
            spf.CreateFolder_ClientOM(spFolderCreate.listName, spFolderCreate.fileName);
    }

 [OperationContract]
    void CreateSharePointFolder(SharePointFolderCreate spFolderCreate);

[DataContract]
public class SharePointFolderCreate
{
    private string m_listName;
    private string m_fileName;

    [DataMember]
    public string listName
    {
        get { return m_listName; }
        set { m_listName = value; }
    }

    [DataMember]
    public string fileName
    {
        get { return m_fileName; }
        set { m_fileName = value; }
    }
}

So am I missing something simple here to make this all work?

Answer 1

It may be that the framework is inferring the intended operation because you have the word “Create” prefixing the function name (CreateSharePointFolder). Details of this behaviour can be found here

Although that is all fine for DomainServices and EntityFramework, following the information in that article, it can be inferred that methods beginning “Delete” will be performing a delete of an entity, so must accept an entity as a parameter. The same is true for “Create” or “Insert” prefixed methods. Only “Get” or “Select” methods can take non-entity parameters, making it possible to pass a numeric id (for example) to a “Get” method.

Try changing your method name temporarily to “BlahSharePointFolder” to see if it is this convention of inferrance that’s causing your problem.

Also, as there is no metadata defined for your SharePointFolderCreate DC, you might need to decorate the class (in addition to the [DataContract] attribute) with the [MetadataType] attribute. You will see how to implement this if you used the DomainServiceClass wizard and point to an EF model. There is a checkbox at the bottom for generating metadata. Somewhere in your solution.Web project you should find a domainservice.metadata.cs file. In this file, you will find examples of how to use the [MetadataType] attribute.

For the RIA WCF service to work correctly with your own methods, you need to ensure that all entities existing on the parameter list have at least one member with a [Key] attribute defined in their metadata class, and that the entity is returned somewhere on your DomainService in a “Get” method.

HTH

Lee