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MVC - Populate Two Dropdowns From Database in Partial View with ViewModel

Here's the visual of what I'm trying to do.
So basically what happens here is that you choose a name from the select on the left and a team from the select on the right, then click Submit Assignment and it adds a record. (This information is for reference so you can understand the context. I don't need help with the database inserts or updates.)
This is going to be a PartialView with a ViewModel.
I need to know how to populate those two dropdowns with separate lists. I'm assuming those would be coming over in the ViewModel.
So in my main view, I have a call to the PartialView with RenderAction.
//The action //The controller
#{Html.RenderAction("TeamAssignment", "TeamAssignment");}
The controller that gets called
public class TeamAssignmentController : Controller
{
MyDatabaseEntities db = new MyDatabaseEntities();
[ChildActionOnly]
public ActionResult TeamAssignment()
{
//NEED A VIEW MODEL HERE TO PASS INTO THE PARTIALVIEW
return PartialView();
}
}
In the ViewModel I will need lists that populate the two drop downs.
The linq query on the left for Name would be this.
var nameList = (from p in db.Participant
where p.ParticipantType == "I"
select new {
p.ParticipantID,
p.IndividualName
}).ToList();
The linq query on the right for Team would be this.
var teamList = (from p in db.Participant
where p.ParticipantType == "T"
select new {
p.ParticipantID,
p.TeamName
}).ToList();
How can I pass that information into the PartialView and how do I populate the dropdowns with the ID for value and name for display text?
UPDATE
I belive this may be the ViewModel I need. Is this correct?
public class TeamAssignmentViewModel
{
//Need these ints for the updating and deleting
public int IndividualParticipantID { get; set; }
public int TeamParticipantID { get; set; }
public List<Participant> NameList { get; set; }
public List<Participant> TeamList { get; set; }
}

You need to create an instance of a viewmodel, populate it and pass it to your PartialView:
[ChildActionOnly]
public ActionResult TeamAssignment()
{
// Instantiate A VIEW MODEL HERE TO PASS INTO THE PARTIALVIEW
MyCustomModel model = new MyCustomModel();
model.nameList = (from p in db.Participant
where p.ParticipantType == "I"
select p).ToList();
model.teamList = (from p in db.Participant
where p.ParticipantType == "T"
select p).ToList();
return PartialView("TeamAssignment", model);
}
EDITED: removed use of dynamic class in linq statements
The markup for the Dropdowns might look something like:
#Html.DropDownListFor(model => model.IndividualParticipantID,
new SelectList(Model.NameList, "ParticipantID", "FirstName")
#Html.DropDownListFor(model => model.IndividualParticipantID,
new SelectList(Model.TeamList, "ParticipantID", "Team")

I'll start by admitting that I haven't read everything posted, but I can help with passing data to the PartialView to be used as a model.
In your View, you can build the partial like this:
#Html.Partial("_PartialViewName", currentItem,
new ViewDataDictionary {
{ "ExtraValue", Model.Count },
{ "SecondExtraValue", #ViewBag.ValueToPass });
Then in the PartialView, you can do this:
#model [Type of currentItem from above]
#{
// I'm using var here for shorthand, whereas I do strong typing and cast in my codebase.
var dataValue = ViewData["ExtraValue"];
var secondDataValue = ViewData["SecondExtraValue"];
}
Using this method you can pass in a model, as well as other values that may be needed for rendering.
Hope this helps. :)

Transitioning from classic asp to asp.net MVC

I am in the habit of using nested loops in classic. Data from the first record set is passed to the second record set. How would I accomplish the same thing in MVC? As far as I can tell, I can only have one model passed to my view.
<%
rs.open "{Call usp_SalesOrder}",oConn
Do While (NOT rs.EOF)
%>
<div><% = rs("SalesOrderNumber")%></div>
<%
rs2.open "{Call usp_SalesOrderLines(" & rs("SOKey") & ")}",oConn
Do While (NOT rs.EOF)
%>
<div><% = rs2("SalesOrderLineNumber")%></div>
<%
rs2.MoveNext
Loop
rs2.close
%>
<%
rs.MoveNext
Loop
rs.close
%>

My suggestion would be to build a more robust model. It is true that you can only pass one model to your view, but your model can contain the results of multiple data sets, provided you have gathered those data sets in your controller and assigned them to the model.
I also suggest staying away from the ViewBag. It's an easy trap to fall into. Trust me when I say you'll regret it later.
For your example, maybe a model defined like this:
public class MyModel
{
public List<SalesOrder> SalesOrders = new List<SalesOrder>();
}
public class SalesOrder
{
public string SOKey = string.Empty;
public List<SalesOrderLine> SalesOrderLines = new List<SalesOrderLine>();
}
And the code to populate the sales orders in the controller:
public Action Index()
{
MyModel model = new MyModel();
model.SalesOrders.AddRange(CallUspSalesOrder());
foreach (SalesOrder salesOrder in model.SalesOrders)
{
salesOrder.SalesOrderLines.AddRange(CallUspSalesOrderLines(salesOrder.SOKey));
}
return View(model);
}
That way, you have access to all sales orders (and their sales order lines) within the view.

I would say that Nathan's post is a good start. Here is what I would do from beginning to end.
This is how I would do my model:
public class SalesOrderModel
{
public List<SalesOrderLines> SOLines = new List<SalesOrderLines>();
public List<SalesOrder> SOHeader = new List<SalesOrder>();
}
My Controller would then do this:
public ActionResult Index()
{
List<SalesOrder> SalesOrder = callSalesOrderUSP.ToList();
List<SalesOrderLines> SalesOrderLines = new List<SalesOrderLines>();
foreach (var thing in SalesOrder)
{
SalesOrderLines.AddRange(callSalesOrderLinesUSP(thing.SOKey).ToList());
}
SalesOrderModel salesOrderModel = new SalesOrderModel
{
SOHeader = SalesOrder,
SOLines = SalesOrderLines
};
return View(salesOrderModel);
}
Then in your view you can do this:
#foreach(var something in Model.SOHeader)
{
foreach (var thing in Model.SOLines.Where(i => i.SOKey == something.SOKey))
{
//display info here
}
}

You can use ViewBag to pass elements not relevant to your model. Also do not be afraid of creating your own ModelView objects that can work between your View and Controller. Your views should not be restricted to what your model has to offer.
Take a look at this for how you can implement a ViewModel in MVC.
And perhaps look at this to see how you can use ViewBag to pass values to your view, not relevant to your model.

C# MVC pass certain rows to the view

I am new to mvc and cannot figure out how to pass a single column of data to the view.
I have connected my db with ado.net entity model to models.
Then in my controller I have :
public class HomeController : Controller
{
shdesignEntities2 _db;
public ActionResult Index()
{
_db = new shdesignEntities2();
ViewData.Model = _db.tblKategoris.ToList();
return View();
}
}
In the view :
#foreach(var m in ViewData.Model)
{
<p>Kategori Ad :</p><p> #m.kategori_ad </p>
}
When I do like this , I pass the whole table data to the view where I only need a single column of information.
How can I only pass data from the column kategori_ad ?

Use Select:
ViewData.Model = _db.tblKategoris.Select(x => x.kategori_ad).ToList();

You can use LINQ to find the object that you want and then pass it to the view, do something like this:
public ActionResult Index()
{
_db = new shdesignEntities2();
ViewData.Model = _db.tblKategoris.Select(x => x.kategori_ad).ToList();
return View();
}
That way ViewData.Model only has the object that matches the linq query.
Here you can find more about Linq to retrieve data from a collection in C#: http://code.msdn.microsoft.com/101-LINQ-Samples-3fb9811b

In Controller
ViewData["Rows"] = (from c in _db.tblKategoris
select c.kategori_ad).ToList();
View
#foreach(var m in (List<string>)ViewData["Rows"])
{
<p>Kategori Ad :</p><p> #m </p>
}

You may look at ViewModels. Also by this way you can use smaller part of data exposed.
For example
public class KategoriViewModel
{
public IEnumerable<Kategori> Kategoriler { get; set; }
}
Then you should add a controller action like
public ActionResult Something()
{
var model = new KategoriViewModel;
model.Kategoriler = your query..;
return View(model);
}
In view
#model KategoriViewModel
#foreach(var m in ViewData.Model)
{
<p>Kategori Ad :</p><p> #m.kategori_ad </p>
}

Passing a parameter back to a view after performing a form action?

I have a view that loads a record with a certain record number. Once the page is loaded, it gives the user an opportunity to login for additional information. Once the login logic is performed, I need to return to that same view with the same record number intact. I am passing the record number to the action using a hidden input in the form. What I can't seem to figure out is how to return to that same view and provide it with that record #. The code I am trying below is not working. I know this is MVC 101 stuff but a hint in the right direction would be appreciated, or feel free to scrap my method and suggest something better!
Form in view:
<form action="/MyView/Authenticate/#item.ID" method="post" enctype="multipart/form-data">
<input name="form_id" type="hidden" value="#item.ID">
.....
Form action:
[HttpPost]
public ActionResult Authenticate()
{
int myid = Convert.ToInt16(Request["form_id"]);
.....
return View("Index", new { id = myid } );
}
EDIT:
It turns out that the correct view is being returned, but it is expecting a model item type of "JobSummaryModel" per the Index action result below. So the question I actually need answered is, how do I pass both the record id and this view model to it?
public ActionResult Index(int id = 0)
{
List<JobSummaryModel> jdata;
ViewBag.IsResults = false;
if (id != 0)
{
ViewBag.IsResults = true;
}
jdata = db.Jobs.Where(c => c.ID == id).Select(c => new JobSummaryModel() { ID = c.ID, Name = c.Name, City = c.City, PostalCode = c.PostalCode, JobDescription = c.PositionDescription }).ToList();
return View(jdata);
}
EDIT:
Thanks Reddy, your suggestions worked! My only remaining issue is that when I return to my Index view from the Authenticate action, I do not seem to have my "jdata". Is my Index action result not being rerun when I return the Index view via my Authenticate action? I am coming from a web forms background where, in an instance like this, the Load/Init events would automatically run when a form is loaded. Do I need to bind my "jdata" in the Authenticate action and include it in the viewmodel?
EDIT: Resolved. Changed my "return View" to a "return RedirectToAction" to resolve my final issue. Thanks everyone!

Answer For your after Edit:
All you want to pass to view is a int Id and your List<JobSummaryModel> jdata right?
So create a ViewModel JObSummaryModelHelper
Public class JObSummaryModelHelper
{
public int Id {get;set;}
public List<JobSummaryModel> jdata {get;set;}
}
Now in your controller
public ActionResult Index(int id = 0)
{
JObSummaryModelHelper jobDetails = new JObSummaryModelHelper();
jobDetails.Id = id;
ViewBag.IsResults = false;
if (id != 0)
{
ViewBag.IsResults = true;
}
jobDetails .jdata = db.Jobs.Where(c => c.ID == id).Select(c => new JobSummaryModel() { ID = c.ID, Name = c.Name, City = c.City, PostalCode = c.PostalCode, JobDescription = c.PositionDescription }).ToList();
return View(jobDetails );
}
Now make sure your view is set to expect this new viewmodel
#model JObSummaryModelHelper
carry on with your manipulation......

You are better off creating a ViewModel for this like so:
Create a View Model class i.e.
public class AuthViewModel
{
public int MyId { get; set; }
}
In your View put the following directive at the top:
#model AuthViewModel
In your initial [HttpGet] method return the view model:
[HttpGet]
public ActionResult Authenticate()
{
var model = new AuthViewModel { MyId = 123 };
return View("Index", model );
}
It's best to use Html helpers in your view, so you can change it to this:
#using(Html.BeginForm()
{
#Html.HiddenFor(m => m.MyId)
...
}
The above uses naming conventions to post back to the action that you are on.
Then return it to your view like this:
[HttpPost]
public ActionResult Authenticate(AuthViewModel model)
{
int myid = model.MyId;
return View("Index", model );
}
Then you can output using this razor syntax #Model.MyId
It's really worth doing some tutorials to learn the conventions, a small amount of time invested in this will save you a lot of time in the future.

Instead of
return View("Index", new { id = myid } );
could you do
return Index(myid);

pass two models to view [duplicate]

This question already has answers here:
ASP.NET MVC - View with multiple models
(4 answers)
Closed 9 years ago.
I am new to mvc and try to learn it by doing a small project with it. I have a page which is supposed to display that specific date's currencies and weather. so I should pass currencies model and weather model. I have done to pass currencies model and works fine but I dont know how to pass the second model. And most of the tutorials on the shows how to pass only one model.
can you guys give an idea how to do it.
this is my current controller action which sends currency model
public ActionResult Index(int year,int month,int day)
{
var model = from r in _db.Currencies
where r.date == new DateTime(year,month,day)
select r;
return View(model);
}

You can create special viewmodel that contains both models:
public class CurrencyAndWeatherViewModel
{
public IEnumerable<Currency> Currencies{get;set;}
public Weather CurrentWeather {get;set;}
}
and pass it to view.
public ActionResult Index(int year,int month,int day)
{
var currencies = from r in _db.Currencies
where r.date == new DateTime(year,month,day)
select r;
var weather = ...
var model = new CurrencyAndWeatherViewModel {Currencies = currencies.ToArray(), CurrentWeather = weather};
return View(model);
}

You have to create a new model which has to contain the whole objects that you want to pass it to view. You should create a model (class, object) which inherits the base model (class, object).
And other suggestion you may send objects (models) via View["model1"] and View["model2"] or just an array that contains objects to pass it and cast them inside the view which I don't advise .

It sounds like you could use a model that is specific to this view.
public class MyViewModel{
public List<Currencies> CurrencyList {get;set;}
}
and then from your controller you could pass this new View Model into the view instead:
public ActionResult Index(int year,int month,int day)
{
var model = from r in _db.Currencies
where r.date == new DateTime(year,month,day)
select r;
return View(new MyViewModel { CurrencyList = model.ToList() });
}
You can than just add more properties to your view model which contain any other models (Weather model) and set them appropriately.