c# - ASP.NET MVC5 Model Binder - Null when binding collection of collections -

i have researched on net here can me.

i have following viewmodel classes:

public class personeditviewmodel {     public person person { get; set; }     public list<dictionaryrootviewmodel> interests { get; set; } }  public class dictionaryrootviewmodel {     public long id { get; set; }     public string name { get; set; }     public icollection<dictionaryitemviewmodel> items;      public dictionaryrootviewmodel()     {         items = new list<dictionaryitemviewmodel>();     } }  public class dictionaryitemviewmodel {     public long id { get; set; }     public string name { get; set; }     public bool selected { get; set; } } 

in edit view use custom editortemplate layout collection of interests using @html.editorfor(m => m.interests). there 2 editortemplates rendering:

1. dictionaryrootviewmodel.cshtml:

   @model platforma.models.dictionaryrootviewmodel @html.hiddenfor(model => model.id) @html.hiddenfor(model => model.name) @html.editorfor(model => model.items) 

2. dictionaryitemviewmodel.cshtml:

   @model platforma.models.dictionaryitemviewmodel @html.hiddenfor(model => model.id) @html.checkboxfor(model => model.selected) @html.editorfor(model => model.name) 

the problem:

when submitting form using post, interests collection gets populated , interest.items collection empty. request contains (among others) following field names, present when inspecting request.forms data in controller action method.

• interests[0].id
• interests[0].name
• interests[0].items[0].id
• interests[0].items[0].selected

all contain proper values - on controller side, object pvm in method:

[httppost] [validateantiforgerytoken] public actionresult edit(personeditviewmodel pvm) { } 

contains data in interests collection (items correct id , name), each element of collection its' subcollection of items empty.

how make correctly pick model?

as usual - answer in front of me whole time. defaultmodelbinder didn't pick items values passed in request, because "forgot" mark items collection property - field! correct form taking account helpful remark @pjobs:

public list<dictionaryitemviewmodel> items{get;set;}