CODEWITHSUNDEEP
javascriptasp.netasp.net-mvcasp.net-mvc-4
nielsv
nielsv

Reputation: 6820

Use return values only in javascript

I have an action Map in my Controller Address. In the Action Method I get all the addresses like this:

public ActionResult Map()
{
    var model = this.UnitOfWork.AddressRepository.Get();
    return View(model);
}

My Address Model looks like this:

public class Address
{
    public Int32 Id { get; set; }
    public string Street { get; set; }
    public string City { get; set; }
    public Decimal Latitude { get; set; }
    public Decimal Longitude { get; set; }
    public Int32 StreetNumber { get; set; }

    public Int32 RegionId { get; set; }

    public virtual Region Region { get; set; }

    public virtual ICollection<Person> Persons { get; set; }
}

Now I would like to use the latitude and the longitude in the javascript part of the page. How can I do this?

I've tried to the following:

<script>
    var model = @Html.Raw(Json.Encode(Model));
    // at this stage the model javascript variable represents the JSON encoded
    // value of your server side model so that you can access all it's properties:
    alert(model.length);
</script>

But I got this error:

A circular reference was detected while serializing an object of type 'System.Data.Entity.DynamicProxies.Address_F9A550E3CE9AB1122FFC2E0A154FBDCAF8648B6FBCF91A81E35459DCA2E075AA'.

Upvotes: 1

Views: 303

Answers (1)

Roger Far
Roger Far

Reputation: 2384

Like it says you have a circular reference somewhere in your mode, but you can set the json parser with options to avoid circular references.

Better would be to parse your mode into a separate viewmodel:

var model = this.UnitOfWork.AddressRepository.Get().Select(m => new ViewModel{
    Latitude  = m.Latitude,
    Longitude  = m.Longitude,
});
return View(model);

This way you only expose the information to the client that is needed.

If you need only a few parameters you might be better of with something like this:

<script>
    var lat = @Model.Latitude;
    var lon = @Model.Longitude;
    // at this stage the model javascript variable represents the JSON encoded
    // value of your server side model so that you can access all it's properties:
    alert(lat);
</script>

Upvotes: 2

Related Questions