Resolving EntitySetName and predicate/project automatically for WCF Data Service.

gistfile1.cs

using System;
using System.Collections.Generic;
using System.Data.Services.Client;
using System.Data.Services.Common;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using System.Threading.Tasks;

namespace ODataSampleClient
{
    public class DynamicLookup<T>
    {
        DataServiceContext context;
        string repositoryName;

        public DynamicLookup()
        {
            this.context = new DataServiceContext(new Uri("http://localhost:52160/SampleDataService.svc/"));
            repositoryName = this.ResolveEntitySetName(typeof(T));
        }

        public List<K> Lookup<T, K>(Expression<Func<T, bool>> predicate, Expression<Func<T, K>> projection)
        {
            return this.context.CreateQuery<T>(this.repositoryName).Where<T>(predicate).Select<T, K>(projection).ToList<K>();
        }

        public List<T> Lookup<T>(Expression<Func<T, bool>> predicate)
        {
            return this.context.CreateQuery<T>(this.repositoryName).Where<T>(predicate).ToList<T>();
        }

        public List<T> Lookup<T>()
        {
            return this.context.CreateQuery<T>(this.repositoryName).ToList<T>();
        }

        public List<K> Lookup<T, K>(Expression<Func<T, K>> projection)
        {
            return this.context.CreateQuery<T>(this.repositoryName).Select<T, K>(projection).ToList<K>();
        }

        private string ResolveEntitySetName(Type type)
        {
            var entitySetAttribute = 
                (EntitySetAttribute)type.GetCustomAttributes(typeof(EntitySetAttribute), true).FirstOrDefault();

            if (entitySetAttribute != null)
            {
                return entitySetAttribute.EntitySet; 
            }

            return null;
        }
    }
}