Question

After writing webforms for many years, I am trying to make the transition to MVC. I’m having trouble getting away from Datatables and understanding how to create a model class properly. The big hiccup is my datasource is a restful webservice which returns XML.

Currently I am strongly typing the view’s model as a datatable. Am I giving anything up by not using a model class? Am I including to much information in the controller?

The following is just a simple application which takes a querystring value, performs a search using a restful webservice, and spits out the results on the page. It works, but I don’t feel like I’ve created an actual MVC application.

My Controller:

using System.Web.Mvc;
using System.Data;
using System.Configuration;

namespace mvc1.Controllers
{
    public class HomeController : Controller
    {
        dhRestful _datahandler = new dhRestful(ConfigurationManager.ConnectionStrings["service"].ConnectionString);

        //
        // GET: /Home/
        public ActionResult Index(string search = "")
        {
            ViewBag.Title = "You searched for: " + search;

            using (DataTable dt = _datahandler.get("tv_show?name=" + search))
            {
                return View(dt);
            }
        }

    }
}

dhRestful is a helper class I ported from a previous project. It makes restful webservice calls and serializes the response XML into a DataTable. If I should continue using this class, where should I be putting it in the project files?

using System.Data;
using System.Xml;

namespace mvc1
{
    public class dhRestful
    {
        string _hostPath = "";

        public dhRestful(string hostPath)
        {
            _hostPath = hostPath;
        }

        public DataTable get(string partialUrl)
        {
            using (XmlTextReader xr = new XmlTextReader(_hostPath + partialUrl))
            {
                using (DataSet ds = new DataSet())
                {
                    ds.ReadXml(xr);

                    if (ds.Tables.Count > 0)
                    {
                        return ds.Tables[0];
                    }
                    else
                    {
                        return new DataTable();
                    }
                }
            }
        }
    }
}

The View using razor:

@model System.Data.DataTable

<h2>@ViewBag.Title</h2>

<table border="1">
    <thead>
        <tr>
            <th>ID</th>
            <th>Show Name</th>
        </tr>
    </thead>
    <tbody>
        @foreach (System.Data.DataRow row in Model.Rows)
        {
            <tr>
                <td>@row["id"].ToString()</td>
                <td>@row["name"].ToString()</td>
            </tr>
        }       
    </tbody>
</table>

Sample XML where the search was on the name “Stargate”:

<myService>
  <tv_show>
    <id>72449</id>
    <name>Stargate SG-1 </name>
  </tv_show>
  <tv_show>
    <id>83237</id>
    <name>Stargate Universe </name>
  </tv_show>
  <tv_show>
    <id>70852</id>
    <name>Stargate: Infinity </name>
  </tv_show>
  <tv_show>
    <id>70851</id>
    <name>Stargate Atlantis </name>
  </tv_show>
</myService>

Answer 1

I would recommend you to write this data access layer via dependency injection, at Composition root. So later on instead of a rest client you can inject a different client that satisfies a contract.

Another note, is to create view models. If you are VO’s or DTO’s that you are using directly within you application it is a good practice to wrap them. I guess this is your answer. You can have your view Models in Model folder or you can create subfolder etc.

Something like this:

   // you need to adjust your dependency accordingly
   Interface IRepository<T> : where t has a value
   {
     void Set(T item);
     T Get(some value that you indicate in T);
   }

    namespace mvc1.Controllers
    {
        public class HomeController : Controller
        {
            IRepository<SomeObject> _repo;

            public HomeController(IRepository<SomeObject> repository)
            {
               _repo = repository;
            }             


            //
            // GET: /Home/
            public ActionResult Index(string search = "")
            {
                ViewBag.Title = "You searched for: " + search;

                using (SomeObject obj = _repo.get("tv_show?name=" + search))
                {
                    // here you can use automapper to map a DTO or VO to View model.
                    FooViewModel model = someobject;
                    return View(model);
                }
            }

        }
    }

At composition root: global.asax you can bootstrap the container. Many ways to this, look at structure map and how to use container.