DropDownList Initial Value Duplicated - MVC 5 - drop-down-menu

I have a #foreach in my View that makes a table. Each row has two items within it's td. When I click my Edit button, the visible item's in a row disappear (DislayFor's) and the hidden items in the row appear (DropDownList)
View Code
<td class="col-md-3">
<span class="item-display">
<span style="font-size: 17px">
#Html.DisplayFor(modelItem => item.Movie.Name)
</span>
</span>
<span class="item-field">
#Html.DropDownList("movieID", item.Movie.Name)
</span>
</td>
By doing this I can select a new value in the DropDownList and then Save that change to my Database (then hiding the DropDownList and unhiding the DisplayFor.
Everything works fine, however I have an issue with the initally selected value, it appears twice with the initial value having an actual value of 0 (which relates to nothing in the DB).
Picture Example
QUESTION:
Right now my dropdown add's a value upon clicking Edit, the item initially selected has the correct name but it is given the index of 0 (which is invalid for my database).
I want to have the initially selected item to NOT be added, but rather to set the selector of the dropdown to the CORRECT INDEX of the appropriate item. I am not sure why it duplicates my selected item twice.
Controller Code
public ActionResult Index(string Filter, string searchString)
{
if (String.IsNullOrEmpty(searchString) || String.IsNullOrEmpty(Filter) || (Int32.Parse(Filter) == 0))
{
ViewBag.employeeID = new SelectList(db.Employees, "ID", "Name", );
ViewBag.movieID = new SelectList(db.Movies, "ID", "Name", initiallySelectedValue);
ViewBag.roleID = new SelectList(db.Roles, "ID", "RoleType");
var movieemployees = db.MovieEmployees.Include(m => m.Employee).Include(m => m.Movie).Include(m => m.Role);
return View(movieemployees.ToList().OrderBy(x => x.Employee.Name));
}
else
{
ViewBag.employeeID = new SelectList(db.Employees, "ID", "Name");
ViewBag.movieID = new SelectList(db.Movies, "ID", "Name");
ViewBag.roleID = new SelectList(db.Roles, "ID", "RoleType");
var parameter = Int32.Parse(Filter);
return View(db.MovieEmployees.Include(m => m.Employee).Include(m => m.Movie).Include(m => m.Role).Where(x => (parameter == 1 && x.Movie.Name.Contains(searchString)) || (parameter == 2 && x.Employee.Name.Contains(searchString)) || (parameter == 3 && x.Role.RoleType.Contains(searchString))).Distinct().ToList().OrderBy(x => x.Employee.Name));
}
}

Your understanding of the parameters for DropDownList isn't quite correct, but you're close! The second parameter for DropDownList (in your case item.Movie.Name) is adding an option label. If you replaced that with a hard-coded string that would serve as a good example of what it's doing (you would see that string as the first option of every select input).
It sounds to me like you want to delete that last parameter since it will only end up serving as a duplicate. Your code would simply look like this:
#Html.DropDownList("movieID")
The important part of your code is where you're building the object that you're storing in ViewData with the key movieID. You didn't post your controller code, but I imagine it looks something like:
var movies = movieRepository.GetAllMovies();
ViewData["movieID"] = new SelectList(movies, "Name", "Id", initiallySelectedValue);
Where Name and Id are the names of properties on the movie object and initiallySelectedValue is rather self explanatory.
Edit
Here is an example of how I would go about solving your problem:
Controller
public ActionResult Index() {
//Get all the possible movies that can be selected
var movies = movieRepository.GetAllMovies();
//Get a list of employees with their related favorite movie record
var employeesWithFavoriteMovie = movieRepository.GetEmployeesWithMovie();
var employeeModels = new List<EmployeeModel>();
//Iterate through the list of employees and their favorite movie, and build the model
foreach (var employeeWithFavoriteMovie in employeesWithFavoriteMovie) {
employeeModels.Add(new EmployeeModel() {
FirstName = employeeWithFavoriteMovie.FirstName,
FavoriteMovieId = employeeWithFavoriteMovie.Movie.Id,
MovieSelectList = new SelectList(movies, "Name", "Id", employeeWithFavoriteMovie.Movie.Id)
});
}
return View(employeeModels);
}
View
#model IEnumerable<WebApplication1.Controllers.EmployeeModel>
#foreach (var employeeModel in Model) {
#Html.DropDownList("Test", employeeModel.MovieSelectList)
}
Notice how a SelectList was built for each employee and that each list is then populated with that employees current favorite movie id. This will now put you in a position to have a properly built SelectList for each employee.

#Html.DropDownListFor(model => model.classmasterd_HCF[i].TD_TEACHER, new SelectList(Model.Teacher, "ParamKey", "ParamValue", Model.classmasterd_HCF[i].TD_TEACHER) as SelectList, new { #class = "form-control input-sm DtlField EditableCtrl", #style = "min-width:100%;", #disabled = "disabled" })
where Teacher in Model.Teacher is a model with code in paramKey and description in paramvalue. Selected value saved in TD_TEACHER field

Related

ViewBag oddity in creating a MultiSelectList

I have spent a lot of time scouring the various forums for help on MultiSelectLists in asp.net MVC3. Finally figured out how to solve my issue now I'm trying to cut down on my code and I've come across something weird with ViewBags. First the code, than I'll explain the behavior.
My function that creates the MultiSelectList to used by the Controller
public MultiSelectList GetPermissionList(string[] selectedValues)
{
List<SelectListItem> permissions = new List<SelectListItem>()
{
new SelectListItem{ Value = "", Text = "None"},
new SelectListItem{ Value = "View", Text = "View"},
new SelectListItem{ Value = "Add", Text = "Add"},
new SelectListItem{ Value = "Edit", Text = "Edit"},
new SelectListItem{ Value = "Delete", Text = "Delete"}
};
return new MultiSelectList(permissions, "Value", "Text", selectedValues);
}
partial code from the edit action from the controller
public ActionResult Edit(int id)
{
ViewBag.Title = "Edit a Security Role";
SecurityRoles securityroles = Repository.Details(id);
ViewBag.Orders = securityroles.Orders.Split(',');
ViewBag.OrdersListBox = GetPermissionList(ViewBag.Orders);
return View(securityroles);
}
partial code from the View
<td class="rightAlign topAlign editor-label">
#Html.MyLabel(m => m.Orders, "lblOrders")
</td>
<td class="editor-field">
#Html.ListBoxFor(m => m.Orders, ViewBag.OrdersListBox as MultiSelectList, new { size = "5" })
</td>
Keep in mind I've cut out a large chunk of code from the edit Action, I have roughly 9 list boxes I'm creating for this security role manager.
My goal, in the edit action is to simply have 1 line of code, calling the GetPermissionList and having it return to the viewbag so I can just display that in the view, as opposed to the 2 lines per listbox that I currently have.
Just looking at the code, it seems obvious if I were to make the call this way:
ViewBag.OrdersListBox = GetPermissionList(securityroles.Orders.Split(','));
It should work, but the selected values do not come through. To compound the oddity, here is something else I tried and it worked fine, but it makes no sense why.
ViewBag.Orders = securityroles.Orders.Split(',');
ViewBag.OrdersListBox = GetPermissionList(securityroles.Orders.Split(','));
ViewBag.Orders plays no role in the ViewBag.OrdersListBox nor is it used in the view, but when I simply assign it a value than the 2nd line of code works.
Does this make sense to anyone? Any suggestions on how to create a way for the GetPermissionList to simply work correctly by sending it a string array instead of passing it the ViewBag object?
I think, You have to set Orders because that is what the selected values are being bound to when the selection happens. You could just pass a string[] if you didn't want to have anything preselected. Check out Darin's answer in this post. He is using a model but i think the same concept applies to view bag.
Multiselect with ViewModel

Editing form with dropdownlist, showing value in dropdownlist

I have editing form with dropdownlist. It's work properly but when I'm on a editin page, in dropdownlist I see first value from a list. I want make, I can see value which I have in database. ex. I have company: 1, 2, 3, 4, 5, and when I editing I have default company 1. But in databese for this product is company 4. Do if I will editin form in dropdownlist I would like have defoult showing company 4 instead 1.
I hope you understand what I have on the mind.
Controller:
[HttpGet]
public ActionResult edytuj_prod(int ID_Produkt)
{
var prod = (from d in baza.Produkts
join s in baza.Firmas on d.ID_firma equals s.ID_firma where ID_Produkt == d.ID_Produkt
select new { d.ID_firma, d.nazwa_prod, d.ilosc, d.jednostka, d.cena, d.ID_Produkt, s.nazwa }).First();
var firma = baza.Firmas;
produktModel pr = new produktModel()
{
firmaList = firma.AsEnumerable().Select(x => new SelectListItem
{
Value = x.ID_firma.ToString(),
Text = x.nazwa
})
};
pr.nazwa_prod = prod.nazwa_prod;
pr.ilosc = prod.ilosc;
pr.jednostka = prod.jednostka;
pr.cena = prod.cena;
return View(pr);
View:
<div class="editor-field">
#Html.DropDownListFor(x => x.ID_firma, Model.firmaList)
</div>
If I understood correctly, you want the dropdown list to have the saved item selected instead of having the first item on the list. If so, see this answer
Also you could check these constructors:
public SelectList(IEnumerable items, Object selectedValue)
public SelectList(IEnumerable items, string dataValueField, string dataTextField, Object selectedValue)

dropdownlist set selected value in MVC3 Razor

Here is my model:
public class NewsCategoriesModel {
public int NewsCategoriesID { get; set; }
public string NewsCategoriesName { get; set; }
}
My controller:
public ActionResult NewsEdit(int ID, dms_New dsn) {
dsn = (from a in dc.dms_News where a.NewsID == ID select a).FirstOrDefault();
var categories = (from b in dc.dms_NewsCategories select b).ToList();
var selectedValue = dsn.NewsCategoriesID;
SelectList ListCategories = new SelectList(categories, "NewsCategoriesID", "NewsCategoriesName",selectedValue);
// ViewBag.NewsCategoriesID = new SelectList(categories as IEnumerable<dms_NewsCategory>, "NewsCategoriesID", "NewsCategoriesName", dsn.NewsCategoriesID);
ViewBag.NewsCategoriesID = ListCategories;
return View(dsn);
}
And then my view:
#Html.DropDownList("NewsCategoriesID", (SelectList)ViewBag.NewsCategoriesID)
When i run, the DropDownList does not select the value I set.. It is always selecting the first option.
You should use view models and forget about ViewBag Think of it as if it didn't exist. You will see how easier things will become. So define a view model:
public class MyViewModel
{
public int SelectedCategoryId { get; set; }
public IEnumerable<SelectListItem> Categories { get; set; }
}
and then populate this view model from the controller:
public ActionResult NewsEdit(int ID, dms_New dsn)
{
var dsn = (from a in dc.dms_News where a.NewsID == ID select a).FirstOrDefault();
var categories = (from b in dc.dms_NewsCategories select b).ToList();
var model = new MyViewModel
{
SelectedCategoryId = dsn.NewsCategoriesID,
Categories = categories.Select(x => new SelectListItem
{
Value = x.NewsCategoriesID.ToString(),
Text = x.NewsCategoriesName
})
};
return View(model);
}
and finally in your view use the strongly typed DropDownListFor helper:
#model MyViewModel
#Html.DropDownListFor(
x => x.SelectedCategoryId,
Model.Categories
)
just in case someone comes with this question, this is how I do it, please forget about the repository object, I'm using the Repository Pattern, you can use your object context to retrieve the entities. And also don't pay attention to my entity names, my entity type Action has nothing to do with an MVC Action.
Controller:
ViewBag.ActionStatusId = new SelectList(repository.GetAll<ActionStatus>(), "ActionStatusId", "Name", myAction.ActionStatusId);
Pay attention that the last variable of the SelectList constructor is the selected value (object selectedValue)
Then this is my view to render it:
<div class="editor-label">
#Html.LabelFor(model => model.ActionStatusId, "ActionStatus")
</div>
<div class="editor-field">
#Html.DropDownList("ActionStatusId")
#Html.ValidationMessageFor(model => model.ActionStatusId)
</div>
I think it is pretty simple, I hope this helps! :)
I drilled down the formation of the drop down list instead of using #Html.DropDownList(). This is useful if you have to set the value of the dropdown list at runtime in razor instead of controller:
<select id="NewsCategoriesID" name="NewsCategoriesID">
#foreach (SelectListItem option in ViewBag.NewsCategoriesID)
{
<option value="#option.Value" #(option.Value == ViewBag.ValueToSet ? "selected='selected'" : "")>#option.Text</option>
}
</select>
Well its very simple in controller you have somthing like this:
-- Controller
ViewBag.Profile_Id = new SelectList(db.Profiles, "Id", "Name", model.Profile_Id);
--View (Option A)
#Html.DropDownList("Profile_Id")
--View (Option B) --> Send a null value to the list
#Html.DropDownList("Profile_Id", null, "-- Choose --", new { #class = "input-large" })
Replace below line with new updated working code:
#Html.DropDownList("NewsCategoriesID", (SelectList)ViewBag.NewsCategoriesID)
Now Implement new updated working code:
#Html.DropDownListFor(model => model.NewsCategoriesID, ViewBag.NewsCategoriesID as List<SelectListItem>, new {name = "NewsCategoriesID", id = "NewsCategoriesID" })
I want to put the correct answer in here, just in case others are having this problem like I was. If you hate the ViewBag, fine don't use it, but the real problem with the code in the question is that the same name is being used for both the model property and the selectlist as was pointed out by #RickAndMSFT
Simply changing the name of the DropDownList control should resolve the issue, like so:
#Html.DropDownList("NewsCategoriesSelection", (SelectList)ViewBag.NewsCategoriesID)
It doesn't really have anything to do with using the ViewBag or not using the ViewBag as you can have a name collision with the control regardless.
I prefer the lambda form of the DropDownList helper - see MVC 3 Layout Page, Razor Template, and DropdownList
If you want to use the SelectList, then I think this bug report might assist - http://aspnet.codeplex.com/workitem/4932
code bellow, get from, goes
Controller:
int DefaultId = 1;
ViewBag.Person = db.XXXX
.ToList()
.Select(x => new SelectListItem {
Value = x.Id.ToString(),
Text = x.Name,
Selected = (x.Id == DefaultId)
});
View:
#Html.DropDownList("Person")
Note:
ViewBag.Person and #Html.DropDownList("Person") name should be as in view model
To have the IT department selected, when the departments are loaded from tblDepartment table, use the following overloaded constructor of SelectList class. Notice that we are passing a value of 1 for selectedValue parameter.
ViewBag.Departments = new SelectList(db.Departments, "Id", "Name", "1");
For anyone that dont want to or dont make sense to use dropdownlistfor, here is how I did it in jQuery with .NET MVC set up.
Front end Javascript -> getting data from model:
var settings = #Html.Raw(Json.Encode(Model.GlobalSetting.NotificationFrequencySettings));
SelectNotificationSettings(settings);
function SelectNotificationSettings(settings) {
$.each(settings, function (i, value) {
$("#" + value.NotificationItemTypeId + " option[value=" + value.NotificationFrequencyTypeId + "]").prop("selected", true);
});
}
In razor html, you going to have few dropdownlist
#Html.DropDownList(NotificationItemTypeEnum.GenerateSubscriptionNotification.ToString,
notificationFrequencyOptions, optionLabel:=DbRes.T("Default", "CommonLabels"),
htmlAttributes:=New With {.class = "form-control notification-item-type", .id = Convert.ToInt32(NotificationItemTypeEnum.GenerateSubscriptionNotification)})
And when page load, you js function is going to set the selected option based on value that's stored in #model.
Cheers.

How to set exist value as selected in dropdown list without hardcoding items in dropdownlist using asp.net mvc?

i have form in asp.net mvc that retrieves records from database.this form have dropdowns. in Edit action of controller it is must to have selected the already inserted items. suppose if i am taking the User information for edit, then its City,State and country must be selected as they inserted before.Can any one tell me how to set values from database as selected in drop down list when page loads???
Assuming you have a user model with State as property you need to do the following for your view
<div class="editor-field">
#Html.DropDownListFor(model => model.State, (SelectList)ViewBag.StateDDL)
#Html.ValidationMessageFor(model => model.State)
</div>
here is the code for the controller
public ActionResult Edit(string id)
{
UserModel myuser = new UserModel();
Get the user data from database here
myuser.State = "AZ";
List<SelectListItem> mystate= new List<SelectListItem>();
SelectListItem item = new SelectListItem();
item.Text = " - SELECT - ";
item.Value = "";
mystate.Add(item);
item = new SelectListItem();
item.Text = "CA";
item.Value = "CA";
mystate.Add(item);
item = new SelectListItem();
item.Text = "AZ";
item.Value = "Az";
mystate.Add(item);
ViewBag.StateDDL = new SelectList(mystate.AsEnumerable(), "Value", "Text", myuser .State);
return View(myuser);
}

MVC DropDownListFor() Selected Item is not Selected / Required Validation not run

I am having trouble getting my DropDownList to set the selected item to the value from the model.
The field in the model is just a string for the Title of the users name (Mr, Miss etc..) Below is my code so far.
<td>
#{ var list = new List<SelectListItem>(new[] {
new SelectListItem{ Selected = string.IsNullOrEmpty(Model.Title), Text="",Value=""},
new SelectListItem{ Selected = Model.Title.Equals("Mr"), Text="Mr",Value="Mr"},
new SelectListItem{ Selected = Model.Title.Equals("Mrs"), Text="Mrs",Value="Mrs"},
new SelectListItem{ Selected = Model.Title.Equals("Miss"), Text="Miss",Value="Miss"},
new SelectListItem{Selected = Model.Title.Equals("Ms"), Text="Ms",Value="Ms"}
});
}
#Html.DropDownListFor(m=>m.Title, list)
</td>
I had this problem with MVC 3 and it turned out that I had set ViewBag.Title on my View (using it for the page title). As soon as I changed it to ViewBag.PageTitle, the dropdownlist code started working : #Html.DropDownListFor(model => model.Title, Model.MySelectList)
The reason for this is that in MVC 2/3, any ViewBag / ViewData properties with the same name as those in the Model object get used in preference in DropDownListFor(), so you need to rename them to make sure they don't conflict. Because that seems really flaky, I just stopped using ViewBag entirely and now rely only on the View Model for passing stuff into the View.
The reason this problem is so prevalent is that ViewBag.Title is used in many introductory tutorials and demo code to set the HTML title element, and so inevitably gets adopted as a "best-practice" approach. However, Title is a natural Model property name for use in dropdowns on a "User Details" view.
So it turns out that the only reason it doesn't work is because my field name is Title, I changed it to Prefix and my exact code works. Way too much time spent finding that out...
Here is working code.
<td>
#{ var list = new List<SelectListItem>(new[] {
new SelectListItem {
Selected = string.IsNullOrEmpty(Model.Prefix),
Text="",
Value=""
},
new SelectListItem {
Selected = Model.Prefix.Equals("Mr"),
Text="Mr",
Value="Mr"
},
new SelectListItem {
Selected = Model.Prefix.Equals("Mrs"),
Text="Mrs",
Value="Mrs"
},
new SelectListItem {
Selected = Model.Prefix.Equals("Miss"),
Text="Miss",
Value="Miss"
},
new SelectListItem {
Selected = Model.Prefix.Equals("Ms"),
Text="Ms",
Value="Ms"
}
});
}
#Html.DropDownListFor(m => m.Prefix, list)
</td>

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