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How to implement pagedlist in mvc when using view models?

I am using viewmodel concept in mvc 4. I am posting data to db and as soon as post displaying in grid below also. So I have used view model concept. This is my viemodel class
public class MyViewModel
{
public document upload_document { get; set; }
public IList<document> Upload_List { get; set; }
}
I have many fields in document so I am not posting fields. I have gone through some articles and they are returning something like this: return View(students.ToList());where student is var. But I am returning model in all action methods. Also in view they have written
#model PagedList.IPagedList<ContosoUniversity.Models.Student>
#using PagedList.Mvc;
but I have this in my view
#model c3card.Dal.EDModel.MyViewModel
So, how can return model that contains pagenum,page size? How can I use this pagedlist concept when using view models?

If you need to map your entities to view models and still be able to page through them, then you need to use StaticPagedList. In order for the standard method of using PagedList to work, it needs to be passed a queryable (unevaluated), so that it can limit the query to only pull the proper number of records. If you're mapping to a view model, though, then that's going to evaluate the query.
What you need is something like:
public ActionResult Students(int? page)
{
var pageNumber = page ?? 1;
var pageSize = 10;
var totalStudents = db.Students.Count();
var students = db.Students.Skip((pageNumber - 1) * pageSize).Take(pageSize);
var model = // map `students` to your view model
var pagedList = new StaticPagedList<MyViewModel>(model, pageNumber, pageSize, totalStudents);
return View(pagedList);
}
Then, the model for your view is:
#model PagedList.IPagedList<Namespace.To.MyViewModel>

using View with layout when both require specific Model

I`m writing an ASP.Net MVC application with Razor.
Assume that I have HomeController and some views for it.
1. View1
2. View2
3. View3
All this views use common _MyLayout file, which should look like this:
When the links are clicked, the views are rendered by RenderBody() method.
Each view is strongly typed: it requires its own Model.
Everything was fine untill I decided to add special Model to _MyLayout view.
But now I get error
The model item passed into the dictionary is of type 'TestUp.Models.UserModels.PendingTestsModel', but this dictionary requires a model item of type 'TestUp.Models.UserModels.UserNavigationModel'.
Here is controllers code
public ActionResult View1()
{
ModelForView1 model = new ModelForView1();
return View(model);
}
public ActionResult View2()
{
ModelForView2 model = new ModelForView2();
return View(model);
}
public ActionResult View3()
{
ModelForView3 model = new ModelForView3();
return View(model);
}
Shortly speaking if layout view doesn`t require model, specific method for View is invoked,
model is created, passed to view and everything is ok. But now layout requires model as well so it crashes.
The question is: how do I elegantly resolve this problem?
Desired workflow is:
View1 is requested
Method in controller for this view is called, model instance created, passed to view
Some method for layout is called, model for layout created, passed to layout.
Is it possible to make things work somehow like this?
Thanks.

Create a base model type and have your specific view models extend it. This base model can have a property of type UserNavigationModel. The layout can accept the base model and use the new property as the model for the navigation menu.
public abstract class ModelBase
{
public UserNavigationModel NavigationModel { get; set; }
}
public class ModelForView1 : ModelBase { ... }
public class ModelForView2 : ModelBase { ... }
public class ModelForView3 : ModelBase { ... }
View1:
#model ModelForView1
Layout:
#model ModelBase
#* use Model.NavigationModel for nav bar *#

Passing object to view error

I am getting this error when trying to pass my object to the view. I am new to MVC so please forgive me.
The model item passed into the dictionary is of type 'System.Collections.Generic.List1[<>f__AnonymousType13[System.Int32,System.String,System.Nullable1[System.DateTime]]]', but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable1[MvcApplication1.Models.storageProperty]'
I am trying to pass a list for a table that will show objects from the storageProperty table with the last date (if there is one) from the expenses table. Most properties have had at least one expense audit, some have had many, and others have had none.
Here is the code from the controller:
var viewModel = db.storageProperties.Select(s => new
{
s.storagePropertyId,
s.BuildName,
latestExpenseSurvey = (DateTime?)s.expenses.Max(e => e.expenseDate)
}).ToList();
return View(viewModel);
}
and the #model statement in the view calls for a storageproperty object. I am using mvc3 with the entity framework. It appears obvious that I cannot pass this list object in place of the storageproperty object, but I can't figure out what to do instead, how should I do this?
Thanks in advance.

Never pass anonymous objects to views. You should always pass view models.
So as always in an ASP.NET MVC application you start by defining a view model which will reflect the requirements of your view:
public class MyViewModel
{
public int StoragePropertyId { get; set; }
public string BuildName { get; set; }
public DateTime? latestExpenseSurvey { get; set; }
}
Then in your controller return an IEnumerable<MyViewModel>:
public ActionResult Index()
{
var viewModel = db.storageProperties.Select(s => new MyViewModel
{
StoragePropertyId = s.storagePropertyId,
BuildName = s.BuildName,
LatestExpenseSurvey = (DateTime?)s.expenses.Max(e => e.expenseDate)
}).ToList();
return View(viewModel);
}
and finally strongly type your view to a collection of this view model:
#model IEnumerable<MyViewModel>
<div>
#Html.EditorForModel()
</div>

Your Linq query projects to an anonymous type. You need to create a named type for this projection in order to refer to it from the view.

FormCollection modify keys

How can I override keys in FormCollection (I need this because I have a property bound to multiple CheckBoxes in a View)? I did try this when a post back is in Action:
formCollection["DecisionReasons"] = formCollection["DecisionReasons"].Replace(",false", "").Replace("false,", "").Replace(",","|");
...but when I UpdateModel only the first value is updated in the model (in my model I have a DecisionReason string).
Do I need a ModelBinder (how can I do that?) or is there another way to do this?

Part of View
<div style="width:300px;height:250px;overflow:auto;">
#foreach (var a in (IEnumerable<SelectListItem>)ViewBag.AllDecisionReasons)
{
#Html.CheckBox("DecisionReasons", a.Selected, new { value = a.Value })
<label>#a.Text</label><br />
}
#Html.ValidationMessage("DecisionReasons", (string)Model.DecisionReasons)
if i check more than one checkbox in my View my Model property wich is string is updated with only one value example (if in View i check 2 checkboxes my Model will be updated with first value, so i need that Model property have value "valu1,valu2" and so on.)
sorry for my bad english.

I commented, above, asking for more details, but I get the impression that you're using checkboxes to represent the individual values in a Flags enumeration.
The default model binder doesn't handle mapping flags in this way, but I found a custom model binder that does in this article.
Edit:
OK, I see from your update (which would be better if you added it to your question, rather than posting it as an answer), your model has a comma-delimited string property containing each of the selected DecisionReasons.
I suggest that you consider the use of a ViewModel. The ViewModel is an abstraction of your model that is tailored for the way in which you present it in your view.
You can derive your ViewModel from your Model class, to reduce the amount of work. Consider this (untested) code:
public class MyModel
{
public virtual string DecisionReasons { get; set; }
}
public class MyViewModel : MyModel
{
public string[] DecisionReasonValues { get; set; }
public override string DecisionReasons
{
get
{
return string.Join(",", DecisionReasonValues);
}
set
{
DecisionReasonValues = value.Split(',');
}
}
}
Use MyViewModel as the model for your View and use DecisionReasonValues to render the checkboxes, not DecisionReasons. ASP.NET MVC will populate DecisionReasonValues from your checkboxes but you can access them as a comma-delimeted string through the overridden DecisionReasons property.

How to Post Form from View strongly Typed to ViewModel?

I have a view model as such:
public class MyViewModel
{
public MyObject myObject{ get; set; }
public List<MyList> myList{ get; set; }
}
I have a view with a form strongly typed to MyViewModel
This view allows you to enter values for the properties of MyObject, as well as create a list of MyList objects. The List part works fine although I thought that would be the more difficult of the two.
Assuming MyObject has a property Description I create a textbox to enter the value as such:
#Html.EditorFor(x => x.myObject.Description);
The text box renders with an id of MyObject_Description...The problem is when I post this to my controller action, MyObject does not get bound at all(althought the list items do as they recieve the appropriate IDs of "MyViewModel_MyList[guid].myListValue")
What am I doing wrong here??
EDIT: more info
The first line of the view is:
#model MyApp.ViewModels.MyViewModel
And the Action method:
[HttpPost]
public ActionResult Create(MyViewModel myViewModel)
{
}
I am passing a new MyViewModel into the partial view to begin...
public ActionResult Create()
{
MyViewModel model = new MyViewModel();
return PartialView(model);
}
EDIT 2
Ok When I render my partial view that contains the forms I call :
#{Html.RenderAction("Create", "MyController");}
this is called from within a View of type #model IEnumerable<MyApp.Models.MyObject>
(this view displays a list of currently existing MyOjects, and at the bottom the partial is rendered to allow the user to add another MyObject to the DB)

If you are not already doing so, try creating a editor template (e.g., Views->Shared->EditorTemplates) called MyObject.cshtml. Move your partial view content to this view and then call
#Html.Editor("myObject").
from your parent partial view.

Change your ViewModel to have the Description directly
public class MyViewModel
{
public string Description { get; set; }
public List<MyList> myList{ get; set; }
}
then bind accordingly
#Html.EditorFor(x => x.Description);

I would expect the top line of your view to look something like this:
<%# Page Title="" Language="C#" Inherits="System.Web.Mvc.ViewPage<MyViewModel>" %>
This tells the view that the model it is supplied is of type MyViewModel (a la <T> style).

I don't think the out of the box model binding knows how to bind to complex objects. You're probably going to have to write up some sort of custom model binder.
I'm afraid it's not something I've done since MVC1 so I'm a bit hesitant to give you any sample code because the mechanism may well have changed completely since then. A quick google did turn up this article http://www.learnxpress.com/asp-net-mvc-hosting-6-tips-for-asp-net-mvc-model-binding-2.html and this article http://bradwilson.typepad.com/blog/2010/10/service-location-pt9-model-binders.html.
Edit: I've just seen this answer which might help Retrieving data from view, should I use model binder?