ASP.NET Web API: Advanced Guid Parameters

Question

I have an ApiController with a Get action as follows:

public IEnumerable<Note> Get(Guid userId, Guid tagId)
{
    var userNotes = _repository.Get(x => x.UserId == userId);
    var tagedNotes = _repository.Get(x => x.TagId == tagId);    

    return userNotes.Union(tagedNotes).Distinct();
}

I want the following actions to be directed to this action:

• HTTP: // {somedomain} / API / notes user id = {} Guid & TagID = {GUID}
• Http: // {somedomain} / API / notes user id = {GUID}?
• HTTP: // {somedomain} / API / notes TagID = {GUID}

In what order should I do this?

UPDATE . Be careful, the api controller should not have another GET method without parameters, or you should use the action with one optional parameter.

Answer 1

Nullable (IIRC, (Guid.Empty)

public IEnumerable<Note> Get(Guid? userId = null, Guid? tagId = null)
{
    var userNotes = userId.HasValue ? _repository.Get(x => x.UserId == userId.Value) : new List<Note>();
    var tagNotes = tagId.HasValue ? _repository.Get(x => x.TagId == tagId.Value) : new List<Note>();
    return userNotes.Union(tagNotes).Distinct();
}