public class Supplier
{
    [Key]
    public string Key {get; set; }
    public string Name { get; set; }
}
public class Category
{
    public int ID { get; set; }
    public string Name { get; set; }
    public virtual ICollection<Product> Products { get; set; }
}

public class Product
{
    public int ID { get; set; }
    public string Name { get; set; }
    public decimal Price { get; set; }

    [ForeignKey("Category")]
    public int CategoryId { get; set; }
    public Category Category { get; set; }

    [ForeignKey("Supplier")]
    public string SupplierId { get; set; }
    public virtual Supplier Supplier { get; set; }
}

public static void Register(HttpConfiguration config)
        {
            ODataModelBuilder odataModelBuilder = new ODataConventionModelBuilder();

            var product = odataModelBuilder.EntitySet<Product>("Products");
            var category = odataModelBuilder.EntitySet<Category>("Categories");
            var supplier = odataModelBuilder.EntitySet<Supplier>("Suppliers");

            var edmModel = odataModelBuilder.GetEdmModel();

            supplier.EntityType.Ignore(c => c.Name);

            config.Select(System.Web.OData.Query.QueryOptionSetting.Allowed);
            config.MaxTop(25);
            config.OrderBy(System.Web.OData.Query.QueryOptionSetting.Allowed);
            config.Count(System.Web.OData.Query.QueryOptionSetting.Allowed);
            config.Expand(System.Web.OData.Query.QueryOptionSetting.Allowed);
            config.Filter(System.Web.OData.Query.QueryOptionSetting.Allowed);
            config.Count(System.Web.OData.Query.QueryOptionSetting.Allowed);

            //config.MapODataServiceRoute("ODataRoute", "odata", edmModel); // کانفیگ به صورت معمولی
           config.MapODataServiceRoute("ODataRoute", "odata",
                builder =>
                {
                    builder.AddService(ServiceLifetime.Singleton, sp => edmModel);
                    builder.AddService<IEnumerable<IODataRoutingConvention>>(ServiceLifetime.Singleton, sp => ODataRoutingConventions.CreateDefault());
                });
}

[EnableQuery]
        public IQueryable<Product> Get()
        {
            return new List<Product>
            {
                new Product { Id = 1, Name = "name 1", Price = 11, Category = new Category {Id =1, Name = "Cat1" } },
                new Product { Id = 2, Name = "name 2", Price = 12, Category = new Category {Id =2, Name = "Cat2" } },
                new Product { Id = 3, Name = "name 3", Price = 13, Category = new Category {Id =3, Name = "Cat3" } },
                new Product { Id = 4, Name = "name 4", Price = 14, Category = new Category {Id =4, Name = "Cat4" } },
            }.AsQueryable(); ;
        }

/odata/Products?$select=Id,Name

/odata/Products?$top=3&$skip=2

/odata/Products?$count=true

{@odata.context: "http://localhost:4516/odata/$metadata#Products", @odata.count: 4,…}
@odata.context:"http://localhost:4516/odata/$metadata#Products"
@odata.count:4
value:[{Id: 1, Name: "name 1", Price: 11, SupplierId: 0, CategoryId: 0},…]
0:{Id: 1, Name: "name 1", Price: 11, SupplierId: 0, CategoryId: 0}
1:{Id: 2, Name: "name 2", Price: 12, SupplierId: 0, CategoryId: 0}
2:{Id: 3, Name: "name 3", Price: 13, SupplierId: 0, CategoryId: 0}
3:{Id: 4, Name: "name 4", Price: 14, SupplierId: 0, CategoryId: 0}

/odata/Products?$filter=Id eq 1

/odata/Products?$filter=Id gt 1 and Id lt 3

/odata/Products?$orderby=Id desc

[EnableQuery(PageSize = 10)]

[EnableQuery(AllowedLogicalOperators=AllowedLogicalOperators.Equal)]

var product = odataModelBuilder.EntitySet<Product>("Products");
product.EntityType.Ignore(e => e.Price);

[EnableQuery(AllowedOrderByProperties = "Id,Name")]

public System.Web.Http.IHttpActionResult GetName(int key)
        {
            Product product = Get().Single(c => c.Id == key);            
            return Ok(product.Name);
        }

HTTP/1.1 200 OK
Content-Type: text/plain; charset=utf-8
DataServiceVersion: 3.0
Content-Length: 3

Ali

public class Product
    {
        public int Id { get; set; }
        public string Name { get; set; }

        [NotFilterable, NotSortable]
        public decimal Price { get; set; }

        [ForeignKey(nameof(SupplierId))]
        [NotNavigable]
        public virtual Supplier Supplier { get; set; }
        public int SupplierId { get; set; }


        [ForeignKey(nameof(CategoryId))]
        public virtual Category Category { get; set; }
        public int CategoryId { get; set; }

        [NotExpandable]
        public virtual ICollection<TestEntity> TestEnities { get; set; }
    }

public DateTimeOffset CreatedOn { get; set; }

/odata/Products?$filter=year(CreatedOn) eq 2016

/odata/Products?$filter=CreatedOn lt cast(2017-04-01T04:11:31%2B08:00,Edm.DateTimeOffset)

/odata/Categories?$expand=Products($filter=Id gt 1 and Id lt 5)

/odata/Categories?$expand=Products($select=Id,Name)

public class MyEnableQueryAttribute : EnableQueryAttribute
{
    public override IQueryable ApplyQuery(IQueryable queryable, ODataQueryOptions queryOptions)
    {
       // Don't apply Skip and Top.
       var ignoreQueryOptions = AllowedQueryOptions.Skip | AllowedQueryOptions.Top;
       return queryOptions.ApplyTo(queryable, ignoreQueryOptions);
    }
}

 public class CaseInsensitiveResolver : ODataUriResolver
    {
        private bool _enableCaseInsensitive;

        public override bool EnableCaseInsensitive
        {
            get { return true; }
            set { _enableCaseInsensitive = value; }
        }
    }

config.MapODataServiceRoute("ODataRoute", "odata",
                builder =>
                {
                    builder.AddService(ServiceLifetime.Singleton, sp => edmModel);
                    builder.AddService<IEnumerable<IODataRoutingConvention>>(ServiceLifetime.Singleton, sp => ODataRoutingConventions.CreateDefault());
                    builder.AddService<ODataUriResolver>(ServiceLifetime.Singleton, sp => new CaseInsensitiveResolver()); // how enable case sensitive
                });