Does not contain a definition or extension method- WHEN IT DOES

Question

I've added services into my MVC/EF project to act as a layer between my controller and repositories.

I'm having trouble copying a method from the repo to the service. I'm trying to use Count() in the service but keep receiving error does not contain a definition for 'Count' and no extension method 'Count' accepting a first argument of type .. could be found

I've implemented it exactly the same way as the repository has so I don't know why it's failing

Repositories:

public abstract class Repository<CEntity, TEntity> : IRepository<TEntity> where TEntity : class 
                                                                    where CEntity : DbContext, new()
{
    private CEntity entities = new CEntity();
    protected CEntity context
    {
        get { return entities; }
        set { entities = value; }
    }

    public virtual int Count 
    {
        get { return entities.Set<TEntity>().Count(); }
    }

    public virtual IQueryable<TEntity> All()
    {
        return entities.Set<TEntity>().AsQueryable();
    }
}

public interface IRepository<TEntity> : IDisposable where TEntity : class
{
    int Count { get; }
    IQueryable<TEntity> All();
}

Service:

public class CampaignService : ICampaignService 
{
    private readonly IRepository<Campaign> _campaignRepository;

    public CampaignService(IRepository<Campaign> campaignRepository)
    {
        _campaignRepository = campaignRepository;
    }

    public int Count
    {
        get { return _campaignRepository.Count()**; }
    }

    public IQueryable GetAll()
    {
        return _campaignRepository.All();
    }
}

public interface ICampaignService
{
    int Count{ get; }
    IQueryable GetAll();
}

** it fails on this line.

`Error 4 'MarketingSystem.Repositories.Common.IRepository' does not contain a definition for 'Count' and no extension method 'Count' accepting a first argument of type 'MarketingSystem.Repositories.Common.IRepository' could be found (are you missing a using directive or an assembly reference?)

The GetAll()/All() methods work fine, but Count() doesn't.

Can anyone spot and explain where I'm going wrong?

Answer 1

You are trying to call Count() on repository. Your repository is neither IQueryable<T> nor IEnumerable<T>, so extension method Count() is not available to you. Actually your repository implements only IRepository<TEntity> Which has only three members available - Dispose(), Count and All(). I think you need to call Count property from this interface.

get { return _campaignRepository.Count; }

NOTE - Count is not a method - its a property.