c# - Access parent model data from child in ASP.NET MVC -

i building small web application asp.net mvc c#. have 2 models:

public class parent {     public guid id { get; set; }      public virtual icollection<child> children { get; set; } } public class child {     public guid id { get; set; }      public guid parentid{ get; set; }     public virtual parent parent { get; set; } } 

and have parentview send parent id child controller actionlink, this:

@html.actionlink("something", "childindexmethod", "childcontroller", new { parentid=item.id}, null) 

when clicked, go childindexview , list of children under parent model. there, want able create new child under same parent. create new child need provide parentid new child object. how can retrieve parentid , pass child?

i did this:

if (model.firstordefault() != null)      {          @html.actionlink("new child", "newchild", new { parentid = model.firstordefault().parentid})     }     else     {         //what if model null?     } 

first check if model not null. if not null, take firstordefault object model , pass parentid child. works if there children under parent. if there no children under parent, cannot read parentid , error occurs. how can send parentid child element position?

i know wrong method achieve goal. still learning. also, not able find answer on so. appreciated.

thank you

it seems model in children view ienumerable<child>. have 2 options:

define new viewmodel contains list of child , parentid:

public childlistviewmodel {     public guid parentid {...}     public ienumerable <child> children {...} } 

use view bag

viewbag.parentid = parentid; 

both make parentid available in view if don't have child