Data is empty in Post method asp.net mvc 2 - asp.net-mvc-2

Question

I`m trying to display classes that have properties of type some custom class inside it.
Model:
public class ComplexParent
{
public SimpleChild First { get; set; }
public SimpleChild Second { get; set; }
}
public class SimpleChild
{
public int Id { get; set; }
public string ChildName { get; set; }
public string ChildDescription { get; set; }
}
Controller:
public ActionResult Testify(int id)
{
ComplexParent par = new ComplexParent();
par.First = new SimpleChild() { Id = id };
par.Second = new SimpleChild()
{
Id = id + 1,
ChildName = "Bob",
ChildDescription = "Second"
};
return View("Testify", par);
}
[HttpPost]
public ActionResult Testify(ComplexParent pComplexParent)
{
return View("Testify", pComplexParent);
}
View:
<% using (Html.BeginForm())
{%>
<fieldset>
<legend>Fields</legend>
<%: Html.EditorFor(x => x.First) %>
<br />
<%: Html.EditorFor(x => x.Second.ChildName)%>
<br/>
<br/>
<br/>
<% Html.RenderPartial("SimpleChild", Model.First); %>
<p>
<input type="submit" value="Watch me :-)" />
</p>
</fieldset>
<% } %>
When it comes to Get it works just fine, I can see all the data. But on post pComplexParent parameter is empty (both properties of a complex class are nulls). Probably Im missing something here, but could not get this to work ...
Small addition: view part that only shows editor for name makes Second child not null and name is set to Bob. But I dont understand how to make it just with EditorFor or DisplayFor methods.
UPDATE: Thanks to Darin Dimitrov, who kindly went throught all my code and found what caused this problem. The exact problem was that if you are using display template, asp.net mvc 2 doesnt post any values back and if whole template is has nothing to post back object is null. I still thinking of the way how to get the data, even if you don`t want to edit it. But using editor template does the thing and I have all objects filled with proper data now.

Answer 1

Your view is a bit of a mess. You are using editor templates along with partials for the first child. It is not very clear what fields are included inside the form. I would recommend you using only editor templates:
Model:
public class ComplexParent
{
public SimpleChild First { get; set; }
public SimpleChild Second { get; set; }
}
public class SimpleChild
{
public int Id { get; set; }
public string ChildName { get; set; }
public string ChildDescription { get; set; }
}
Controller:
[HandleError]
public class HomeController : Controller
{
public ActionResult Testify(int id)
{
var par = new ComplexParent();
par.First = new SimpleChild() { Id = id };
par.Second = new SimpleChild()
{
Id = id + 1,
ChildName = "Bob",
ChildDescription = "Second"
};
return View(par);
}
[HttpPost]
public ActionResult Testify(ComplexParent pComplexParent)
{
return View(pComplexParent);
}
}
View:
<% using (Html.BeginForm()) { %>
<%: Html.EditorFor(x => x.First) %>
<%: Html.EditorFor(x => x.Second) %>
<input type="submit" value="Watch me :-)" />
<% } %>
Editor template for SimpleChild (~/Views/Home/EditorTemplates/SimpleChild.ascx):
<%# Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<SomeNs.Models.SimpleChild>" %>
<%: Html.HiddenFor(x => x.Id) %>
<%: Html.EditorFor(x => x.ChildName) %>
<%: Html.EditorFor(x => x.ChildDescription) %>
Now if you want to have different editor templates for the two child properties you could either specify the editor template name when including it:
<%: Html.EditorFor(x => x.First, "FirstChildEditor") %>
which corresponds to ~/Views/Home/EditorTemplates/FirstChildEditor.ascx or use an [UIHint] attribute at your model:
public class ComplexParent
{
[UIHint("FirstChildEditor")]
public SimpleChild First { get; set; }
public SimpleChild Second { get; set; }
}
My recommendation is not to use Html.RenderPartial for generating input fields because their names will be hardcoded and won't bind properly depending on your objects hierarchy.