Sorting and Paging on repository - asp.net-mvc

Question

I have a simple ASP.NET MVC application which has possibility to search, filter and page a list of vehicle makes. I implemented sorting, filtering and paging on controller (on "Index" action) following the tutorials from kudvenkat on youtube https://www.youtube.com/watch?v=srN56uxw76s
So, this is my "VehicleMakeController" and "Index" action:
public class VehicleMakeController : Controller
{
private readonly IVehicleRepository _vehicleRepository;
public VehicleMakeController()
{
_vehicleRepository = new VehicleRepository(new VehicleDbContext());
}
// GET: VehicleMake
public ActionResult Index(string search, int? page, string sort)
{
ViewBag.SortNameParameter = string.IsNullOrEmpty(sort) ? "Name desc" : "";
var makes = _vehicleRepository.AllMakes;
switch (sort)
{
case "Name desc":
makes = makes.OrderByDescending(x => x.Name);
break;
default:
makes = makes.OrderBy(x => x.Name);
break;
}
if (search == null)
{
return View(makes.ToList().ToPagedList(page ?? 1, 5));
}
return View(makes.Where(x => x.Name.ToLower().StartsWith(search)).ToList().ToPagedList(page ?? 1, 5));
}
and this is my "Index" view:
#using PagedList;
#using PagedList.Mvc;
#model IPagedList<Project.Service.Entities.VehicleMake>
#{
ViewBag.Title = "Vehicle Makes";
}
<h2>#ViewBag.Title</h2>
#Html.ActionLink("Create", "CreateVehicleMake")
<br/>
<br/>
#using (#Html.BeginForm("Index", "VehicleMake", FormMethod.Get))
{
<p>
#Html.TextBox("search") <input type="submit" value="Search"/>
</p>
}
<table class="table">
<thead>
<tr>
<th>#Html.ActionLink("Name", "Index", new { sort = ViewBag.SortNameParameter, search = Request.QueryString["search"] })</th>
<th></th>
</tr>
</thead>
<tbody>
#foreach (var vehicleMake in Model)
{
<tr>
<td>#vehicleMake.Name</td>
<td>#Html.ActionLink("Edit", "EditVehicleMake", new {id = vehicleMake.Id})</td>
<td>#Html.ActionLink("Delete", "DeleteVehicleMake", new {id = vehicleMake.Id})</td>
</tr>
}
</tbody>
</table>
#Html.PagedListPager(Model, page => Url.Action("Index", new { page, search = Request.QueryString["search"], sort = Request["sort"]}),
new PagedListRenderOptions() { Display = PagedListDisplayMode.IfNeeded, DisplayPageCountAndCurrentLocation = true})
#if (!Model.Any())
{
<b>No rows match search criteria!</b>
}
In application I'm using repository pattern and I have "AllMakes" method to retrieve all vehicle makes from database. So, this is my "VehicleRepository":
public class VehicleRepository : IVehicleRepository
{
private readonly VehicleDbContext _context;
public VehicleRepository(VehicleDbContext context)
{
_context = context;
}
public IEnumerable<VehicleMake> AllMakes => _context.VehicleMakes;
}
and this is my "IVehicleRepository" interface:
public interface IVehicleRepository
{
IEnumerable<VehicleMake> AllMakes { get; }
}
My DbContext class is following:
public class VehicleDbContext : DbContext
{
public VehicleDbContext() : base("VehicleDbContext")
{
}
public DbSet<VehicleMake> VehicleMakes { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
}
}
This everything works OK, but now I want to implement sorting and paging in repository and remove it from controller. The parameters should be passed trough get/query method. I'm not sure how to do this and I would appreciate any help.

Answer 1

You can declare a function in IVehicleRepository and implement it.
public interface IVehicleRepository
{
IEnumerable<VehicleMake> AllMakes { get; }
List<VehicleMake> GetVehicleWithPagination(string search, int? page, string sort);
}
public class VehicleRepository : IVehicleRepository
{
// your old code
public List<VehicleMake> GetVehicleWithPagination(string search, int? page, string sort)
{
// this is your code from controller
switch (sort)
{
case "Name desc":
makes = AllMakes.OrderByDescending(x => x.Name);
break;
default:
makes = AllMakes.OrderBy(x => x.Name);
break;
}
if (search == null)
{
return AllMakes.ToList().ToPagedList(page ?? 1, 5);
}
}
}
And your controller:
public ActionResult Index(string search, int? page, string sort)
{
ViewBag.SortNameParameter = string.IsNullOrEmpty(sort) ? "Name desc" : "";
return View(_vehicleRepository.GetVehicleWithPagination(search, page, sort));
}