– renderpartial with null model gets passed the wrong type

I have a page:

<%@ Page Inherits="System.Web.Mvc.View<DTOSearchResults>" %>

And on it, the following:

<% Html.RenderPartial("TaskList", Model.Tasks); %>

Here is the DTO object:

public class DTOSearchResults
    public string SearchTerm { get; set; }
    public IEnumerable<Task> Tasks { get; set; }

and here is the partial:

<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<IEnumerable<Task>>" %>

When Model.Tasks is not null, everything works fine. However when its null I get:

The model item passed into the dictionary is of type
'DTOSearchResults' but this dictionary requires a model item of type

I figured it must not know which overload to use, so I did this (see below) to be explicit, but I still get the same issue!

<% Html.RenderPartial("TaskList", (object)Model.Tasks, null); %>

I know I can work around this by checking for null, or not even passing null, but that's not the point. Why is this happening?

Best Solution

Andrew I think the problem you are getting is a result of the RenderPartial method using the calling (view)'s model to the partial view when the model you pass is null.. you can get around this odd behavior by doing:

<% Html.RenderPartial("TaskList", Model.Tasks, new ViewDataDictionary()); %>

Does that help?

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