ModelState.IsValid contains errors when using MongoDB

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I'm trying to create a basic movie database using ASP.NET MVC 4 and MongoDB. My problem is in the POST Update method of my MovieController.                                                                                                                               

[HttpPost]
    public ActionResult Update(Movie movie)
    {
        if (ModelState.IsValid)
        {
            _movies.Edit(movie);
            return RedirectToAction("Index");
        }
        return View();
    }

The ModelState contains an error for the movie's Id field (which is an ObjectId object) and throws the following exception:

 {System.InvalidOperationException: The parameter conversion from type 'System.String' to type 'MongoDB.Bson.ObjectId' failed because no type converter can convert between these types

This is the Update view:

@model MVCMovie.Models.Movie
@{
    ViewBag.Title = "Update";
}
<h2>Update</h2>
@using (Html.BeginForm())
{
    @Html.HiddenFor(m => m.Id);
    @Html.EditorForModel()
    <p>
        <input type="submit" value="Update" />
    </p>
}

And the Movie class in Models:

namespace MVCMovie.Models
{
    public class Movie
    {
        [BsonId]
        public ObjectId Id { get; set; }
        public string Title { get; set; }
        public DateTime ReleaseDate { get; set; }
        public string Genre { get; set; }
        public decimal Price { get; set; }
        [ScaffoldColumn(false)]
        public DateTime TimeAdded { get; set; }
    }
}

I'm assuming that the problem is being caused in the view because it tries to send a string instead of an ObjectId object. But I cannot figure out how to fix this, any ideas?

  1. Post:412

    Points:2888
    Re: ModelState.IsValid contains errors when using MongoDB

    Hi Samuel,

    Have a look at this

    public class MovieModelBinder : IModelBinder
    {
        public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
        {
            var modelBinder = new DefaultModelBinder();
            var movie = modelBinder.BindModel(controllerContext, bindingContext) as Movie;
            var id = controllerContext.HttpContext.Request.Form["Id"];
            if (movie != null)
            {
                movie.Id = new ObjectId(id);
                return movie ;
            }
            return null;
        }
    }

    And change your Update method as so

    public ActionResult Update([ModelBinder(typeof(MovieModelBinder))] Movie movie)

      Modified On Apr-04-2018 04:51:55 AM

Answer