Question

I don’t know if I’ve understanding MVC correctly if my question makes no sense, but I’m trying to understand the following:

I have some code on a controller that returns JSON data.
The JSON data is populated based on a choice from a dropdown box on an Asp.Net page.
I thought (incorrectly) that Session variables would be shared between the Asp.Net project and the MVC Project.
What I’d like to do therefore (if this is possible), is to call a Sub on the MVC that sets a variable before the JSON query is run.

I have the following:

Sub SetCountryID(ByVal CountryID As Integer)
    Me.pCountrySelectedID = CountryID
End Sub

Which I can call by the following:

Response.Write("http://localhost:7970/Home/SetCountryID/?CountryID=44")

But this then results in a blank page – again obviouslly totally incorrect!

Am I going about MVC the wrong way or do I still have a hell of a lot more learning to do?

Is this even possible to do?

Answer 1

The default route will handle an id argument so your action looks like this:

Code Converted from C# by hand please excuse any mistakes

Function Lookup(ByVal id as Integer) as JsonResult
     Dim db as New DbDataContext()
     Return Json(GetMyDataAndReturnObject(), JsonRequestBehavior.AllowGet)
End Function

Call it thusly (jQuery)

$.getJSON('/Controller/Lookup/' + $('#SelectId')[0].options[id].value, function(json) {
      processResult(json);
});