MVC dynamic routeValues for ActionLinks

Question

I have a need to use ActionLink to link to ann edit screen for my ViewModel A.

A has a composite key, so to link to it, the route values will have to have 3 pramaters, like this:

<%: Html.ActionLink("EDIT", "Action", "Controller", 
    new { area = "Admin", Id1= 1, Id2= 2, Id3= 3 })%>

As you can see, the route values contain the ids that the controller Action will accept.

I want to be able to generate the route values from a helper function, like this:

public static Object GetRouteValuesForA(A objectA)
    {
        return new
        {
            long Id1= objectA.Id1,
            long Id2= objectA.Id2,
            long Id3= objectA.Id3
        };
    }

And then use it in the ActionLink helper, but I don't know how to pass that result to the ActionHelper

objectA = new A(){Id1= objectA.Id1,Id2= objectA.Id2,Id3= objectA.Id3};
....
<%: Html.ActionLink("EDIT", "Action", "Controller", 
    new { area = "Admin", GetRouteValuesForA(objectA) })%>

But that would need the controller action to accept that anonymous type instead of a list of 3 properties

I saw the below link that merges anonymous type, but is there any other way to do this? Merging anonymous types

Koblas

Can't you just add the values as properties of your viewmodel? – Seyler

They are, but I just want to use the function to generate the route values in case the definition of A changes, like if I need to add or remove Ids that make up the composite key. That way, I would only have to change the params in one place – Koblas

Answer 1

How about something like this?

Model:

public class AViewModel
{

    public string Id1 { get; set; }
    public string Id2 { get; set; }
    public string Id3 { get; set; }

    public RouteValueDictionary GetRouteValues()
    {
        return new RouteValueDictionary( new { 
            Id1 = !String.IsNullOrEmpty(Id1) ? Id1 : String.Empty,
            Id2 = !String.IsNullOrEmpty(Id2) ? Id2 : String.Empty,
            Id3 = !String.IsNullOrEmpty(Id3) ? Id3 : String.Empty
        });
    }
}

View:

<%: Html.ActionLink("EDIT", "Action", "Controller", Model.GetRouteValues())%>

You can now reuse them as much as you like and only ever have to change them in one place.

Seyler