Dropdown list filled from repository - asp.net-mvc-3

I have an MVC3 drop down list that come from this code on the controller.
private SelectList progCodesList = new SelectList(new[] { "Description", "Requirements", "Development", "Testing", "Documentation" });
How can I fill the fields from a repository, to build the drop down dynamically?
Thanks.

Assuming you have the progCodes in a database table, with progCode having the text, and progCodeId with a unique id, then you can read the table into a list of SelectListItem as follows:
private DbContext _db = new DbContext();
var progCodesList = _db.progCodes.Select(x => new SelectListIem()
{
Text = x.progCode,
value = x.progCodeId
}).ToList();
You can then pass this List<SelectListItem> to your view either in a strongly-typed model, or using the ViewBag.

You need to pass the progCodesList to the ViewBag in your controller method using something like:
ViewBag.ProgCodeId = progCodesList;
Then in your view, you need to fill the drop down like this:
<div class="editor-label">
#Html.LabelFor(model => model.ProgCodeId, "ProgCode")
</div>
<div class="editor-field">
#Html.DropDownList("ProgCodeId", String.Empty)
#Html.ValidationMessageFor(model => model.ProgCodeId)
</div>

Related

Validation of DropDownListFor is not working in MVC3?

Validation is Working on Other Input type text element but not working on DropDownListFor
Class Purchase Input Property Code
[Required]
public string LedgerId { get; set; }
Class View Model Code
PurchaseViewModel purchaseVM = new PurchaseViewModel
{
// PurchaseInput=purchaseInput,
Ledger = uw.LedgerRepository.Get().Select(x => new SelectListItem { Value = x.Id.ToString(), Text = x.LedgerName }),
};
View
<div class="column">
<div class="labelField">
#Html.LabelFor(model => model.PurchaseInput.LedgerId, "Party")
</div>
<div class="ItemField">
#Html.DropDownListFor(model => model.PurchaseInput.LedgerId, new SelectList(Model.Ledger, "Value", "Text"))
#Html.ValidationMessageFor(model => model.PurchaseInput.LedgerId)
</div>
</div>
On the face of it, it seems that you do not have an empty item in your select list. The validation will only trigger if the user selects a dropdown item with string length of zero. If you examine the Html source can you see the validation attributes on the dropdown ( depending on whether you are using unobtrusive validation or not)?
Yes, there are problems with validation of DropDownListFor. look at this link. They get validation data manually from metadata - http://forums.asp.net/t/1649193.aspx
Although this is a workaround, at least it fires some sort of validation. Try:
#Html.DropDownListFor(model => model.PurchaseInput.LedgerId, new SelectList(Model.Ledger, "Value", "Text"), new { #class = "required" })

How are you meant to use Prompt, Description, Ordering when applying data-annotations in ASP.NET MVC 3

I have a view model with a property on it that looks like this:
[Display(Name = "Some Property", Description = "This is description", Prompt = "This is prompt")]
[Required(ErrorMessage = RequiredFieldMessage)]
public string SomeProperty { get; set; }
But this does not seem to render anything extra in the view. Do you need to do some additional work?
<div class="editor-label">
#Html.LabelFor(model => model.SomeProperty )
</div>
<div class="editor-field">
#Html.TextAreaFor(model => model.SomeProperty , 5, 80, null)
#Html.ValidationMessageFor(model => model.SomeProperty )
</div>
Not all of the built in EditorTemplates take advantage of all of the DataAnnotations, but they are there for when you write your own EditorTemplates you can leverage them.
Ordering doesn't really apply unless you are doing DisplayForModel or EditorForModel where its showing multiple editors for all the properties on the model, it can then order the Editor's appropriately.
If you wanted to take advantage of the Description and Prompt metadata you could write your own String EditorTemplate:
#model string
#Html.TextBox("", ViewData.TemplateInfo.FormattedModelValue, new {
#title = ViewData.ModelMetadata.Description,
#placeholder = ViewData.ModelMetadata.Watermark})

Passing a selected value from a partial view to the main view's viewmodel

As ASP.Net MVC3 newbies we have an issue that would like assistance with. (Questions at the bottom of this thread too.)
First of all I am not sure if the following is the best way to go about this so please let me know if we are heading in the wrong direction. We would like to use partial views to do lookups for dropdown lists. In some cases the lookups will be done in multiple places and also, the data is not part of our viewmodel. The data may be coming from a Database or Web Service in our application. Some of the data is loaded at startup and some is based upon other values selected in the form.
We are calling a child action from our main view and returning a partial view with the data we obtained. Once the user selects their choice we are not sure how to store the selected item code in our main view model.
In our main form we call to an action:
#model Apps.Model.ViewModels.AVMApplicationInfo
...
<div class="editor-label">
#Html.LabelFor(m => m.VMResidencyWTCS.DisplayState)
</div>
<div class="editor-field">
#Html.TextBoxFor(m => m.VMResidencyWTCS.DisplayState)
#Html.DropDownListFor(m => m.VMResidencyWTCS.DisplayState, Apps.Model.Helpers.ResidencyStates.StateList)
#Html.ValidationMessageFor(m => m.VMResidencyWTCS.DisplayState)
</div>
#Html.Action("DisplayCounties", "PersonalInfo")
...
In the PersonalInfo controller:
[ChildActionOnly]
public ActionResult DisplayCounties()
{
IList<County> countiesDB = _db.Counties
.OrderBy(r => r.CountyDescr)
.Where(r => r.State == "WI"
&& r.Country == "USA")
.ToList();
//Create an instance of the county partial view model
VMCounty countyView = new VMCounty();
//Assign the available counties to the view model
countyView.AvailableCounties = new SelectList(countiesDB, "CountyCd", "CountyDescr");
return PartialView("_DisplayCounties", countyView);
}
In the _DisplayCounties partial view:
#model Apps.Model.ViewModels.VMCounty
<div class="editor-label">
#Html.LabelFor(m => m.CountyDescr)
</div>
<div class="editor-field">
#Html.DropDownListFor(x => x.SelectedCountyCd, Model.AvailableCounties)
</div>
How do I assign the SelectedCountyCd to a field in the main form view model (Apps.Model.ViewModels.AVMApplicationInfo )? Are there any issues of when the child action/partial view is called; i.e., is it loaded at start up and can this method be used to include a user choice as a filter for the lookup? If so, how could the value be passed to the child controller; viewbag?
You could pass it as parameter to the child action:
#model Apps.Model.ViewModels.AVMApplicationInfo
...
#Html.Action("DisplayCounties", "PersonalInfo", new {
selectedCountyCd = Model.CountyCd // or whatever the property is called
})
and then have the child action take this value as parameter:
[ChildActionOnly]
public ActionResult DisplayCounties(string selectedCountyCd)
{
IList<County> countiesDB = _db.Counties
.OrderBy(r => r.CountyDescr)
.Where(r => r.State == "WI"
&& r.Country == "USA")
.ToList();
//Create an instance of the county partial view model
VMCounty countyView = new VMCounty();
//Assign the available counties to the view model
countyView.AvailableCounties = new SelectList(countiesDB, "CountyCd", "CountyDescr");
// assign the selected value to the one passed as parameter from the main view
countyView.SelectedCountyCd = selectedCountyCd;
return PartialView("_DisplayCounties", countyView);
}

ASP.NET MVC 3 #Html.DropDownListFor ignoring selectedValue

In my asp.net MVC 3 project I would like to create a contact that's related to a company.
You can either directly create a contact OR go via the company details view and add a new contact passing the companyId to set that company already in the dropdown on the contact create form.
The problem is that I can 't get the passed company as default in my dropdown.
Global.asax
routes.MapRoute("contactCreate", "contact/toevoegen/{companyid}", new { action = "ContactCreate", controller = "Backend", companyid = UrlParameter.Optional });
Controller method
public ActionResult ContactCreate(int? companyid)
{
Contact contact = new Contact();
ViewBag.StatusList = srep.getContactStatusses();
ViewBag.CompanyId = companyid;
return View(contact);
}
View
#model xxx.Models.Contact
...
<div class="editor-label">
#Html.LabelFor(model => model.bedrijf_id)
</div>
<div class="editor-field">
#Html.DropDownListFor(model => model.bedrijf_id, new SelectList(ViewBag.Bedrijven, "bedrijf_id", "bedrijf_naam",ViewBag.CompanyId), "--Kies bedrijf--")
#ViewBag.CompanyId
#Html.ValidationMessageFor(model => model.bedrijf_id)
</div>
...
#ViewBag.CompanyId has a value.
Any idea why it's not setting the selected value?
When doing a "DropDownListFor" it will try to match up the value passed in from the model for the selected value. So in your example it will use "bedrijf_id" as the selected value. It looks like you want the selected value to be from something outside of your model.
From the comments I think what you want is just a DropDownList as follows:
#Html.DropDownList("DropDownList", new SelectList((ViewBag.Bedrijven, "bedrijf_id", "bedrijf_naam", ViewBag.CompanyId), "--Kies bedrijf--")
Hope this helps.

UpdateModel not updating the model via ViewModel and property from DropDownListFor

I am trying to set up an Edit view on which I have a text box and DropDownListFor. I have figured out a way to populate the DDLF, and the rendered and posted values are correct, but i cant seem to get the model to update properly.
The object i am trying to update is generated from LINQtoSQL, and in database it has foreign key column. In LINQtoSQL class that resulted in "Contains" relationship. I can get to ID property that represents the column in DB, and also the object that it represents.
zupanija = new Zupanija(); //object that needs to be updated
zupanija.Drzava; //object that i want to change to make the update
zupanija.DrzavaID; //Property linked to object that should change
Only way i have figured out to do the update is to get the value from DDLF and use it to get the object that i want to change like this:
[HttpPost]
public ActionResult Edit(int id, FormCollection collection)
{
var zupanija = repo.ZupanijaById(id);
var drzava = new repoDrzava().DrzavaById(Convert.ToInt32(collection["Zupanija.DrzavaID"]));
zupanija.Drzava = drzava;
}
Also when i try to update the ID field like this, then i get the folowing error:
zupanija.DrzavaID = Convert.ToInt32(collection["Zupanija.DrzavaID"]);
Error: throw new System.Data.Linq.ForeignKeyReferenceAlreadyHasValueException();
This seems to me that it is very lousy way to do this, and i am trying to get UpdateModel to work.
I have found the solution while looking for something else, in blog by Joe Stevens:
Using Controller UpdateModel when using ViewModel
The catch is in following: When view model is used then to correctly bind the properties it is necessary to "instruct" the UpdateModel helper how to find the actual class we wish to update.
My solution required to modify
UpdateModel(zupanija); to UpdateModel(zupanija,"Zupanija");
Because i was using a ViewModel class that contained couple properties along with the main data class i wanted to update.
Here is the code, i hope it helps to understand:
public class ZupanijaFVM
{
public IEnumerable<SelectListItem> Drzave { get; private set; }
public Zupanija Zupanija { get; private set; }
...
}
// From Controller
//
// GET: /Admin/Zupanije/Edit/5
public ActionResult Edit(int id)
{
var zupanija = repo.ZupanijaById(id);
return zupanija == null ? View("Error") : View(new ZupanijaFVM(repo.ZupanijaById(id)));
}
//
// POST: /Admin/Zupanije/Edit/5
[HttpPost]
public ActionResult Edit(int id, FormCollection collection)
{
var zupanija = repo.ZupanijaById(id);
if (TryUpdateModel(zupanija, "Zupanija"))
{
repo.Save();
return RedirectToAction("Details", new { id = zupanija.ZupanijaID });
}
return View(new ZupanijaFVM(zupanija));
}
//From View:
#model VozniRed.Areas.Admin.Models.ZupanijeFVM
<script src="#Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
<script src="#Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>
#using (Html.BeginForm())
{
#Html.ValidationSummary(true)
<fieldset>
<legend>Zupanija</legend>
#Html.HiddenFor(model => model.Zupanija.ZupanijaID)
<div class="editor-label">
#Html.LabelFor(model => model.Zupanija.Naziv)
</div>
<div class="editor-field">
#Html.EditorFor(model => model.Zupanija.Naziv)
#Html.ValidationMessageFor(model => model.Zupanija.Naziv)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.Zupanija.Drzava)
</div>
<div class="editor-field">
#Html.DropDownListFor(model => model.Zupanija.DrzavaID, Model.Drzave)
#Html.ValidationMessageFor(model => model.Zupanija.DrzavaID)
</div>
<p>
<input type="submit" value="Save" />
</p>
</fieldset>
}
<div>
#Html.ActionLink("Back to List", "Index")
</div>
A dropdown list is represented by a <select> tag in an HTML form. A <select> contains a list of <option> tags each containing an ID and a text. When the user selects an option and submits the form the corresponding ID of this options is POSTed to the server. And only the ID. So all you can expect to get in your Edit POST action is the ID of the selected option. And all that UpdateModel does is use the request parameters that are sent and convert them to a strongly typed object. But because all that is a POSTed is a simple ID that's all you can get. From there on you have to query the datastore using this ID if you want to obtain the corresponding model. So you cannot get something that is not existing.

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