Question

I have a main view and the URL for this view has a Action/Controller/Area and id value, something like:

http://localhost:56513/Incident/IncidentHome/Index/8c02a647-a883-4d69-91be-7ac5f7b28ab7

I have a partialview in this main view, one that calls methods in the controller via Ajax. This partial view needs to know the ID value of the url for the parent page. I found how to do this is through ‘ParentActionViewContent’. Something like:

        using (Ajax.BeginForm("UpdatePersonalStatusPanel", "Status", new { area = "Tools" , id = ViewContext.ParentActionViewContext.RouteData.Values["id"].ToString() }, new AjaxOptions { UpdateTargetId = "divPersStatus" }))
        {
            <p style="text-align: center;">
                <span class="editor-label">@Html.LabelFor(m => m.StatusText)</span> <span class="editor-field">@Html.EditorFor(m => m.StatusText)</span>
                <input type="submit" value="Change Current Status" />
            </p>
        }

Now, this works fantastic for calling the controller method. The ID is passed correctly so that the controller can then see it in the routedata. I use the id to perform a database call, and then return the partialview again. The problem is on the return. I get a ‘Object reference not set to an instance of an object’ on the ViewContext.ParentActionViewContext.RouteData.Values[“id”].ToString() bit in the ajax.beginform , and my targetid doesn’t refresh.

Clearly I must be doing something wrong. Does someone else have a better way to see the parent view’s routedata through Ajax?

Answer 1

If I’m understanding you correctly, this partial view calls itself. So ParentActionViewContext works the first time because the first time your main view calls an action using this partial view. However, later an ajax call directly returns this partial view. When the partial view is invoked directly there is no Parent View action hence the null reference on ParentActionViewContext.

Rather than deal with with route data I recommend including the id in the model of your partial view.

new { area = "Tools" , id = Model.Id }