#Html.DropDownListFor(m => m.branch, CommonMethod.getBranch("",Model.branch), "--Select--", new { #multiple = "multiple" })
#Html.DropDownListFor(m => m.division, CommonMethod.getDivision(Model.branch,Model.division), "--Select--", new { #multiple = "multiple" })
I have two instances of DropDownListFor. I want to set selected as true for those which have previously stored values for Model.branch and Model.division. These are string arrays of stored ids
class CommonMethod
{
public static List<SelectListItem> getDivision(string [] branchid , string [] selected)
{
DBEntities db = new DBEntities();
List<SelectListItem> division = new List<SelectListItem>();
foreach (var b in branchid)
{
var bid = Convert.ToByte(b);
var div = (from d in db.Divisions where d.BranchID == bid select d).ToList();
foreach (var d in div)
{
division.Add(new SelectListItem { Selected = selected.Contains(d.DivisionID.ToString()), Text = d.Description, Value = d.DivisionID.ToString() });
}
}
}
return division;
}
}
The returned value of division is selected as true for the selected item in the model, but on view side it is not selected.
Use a ListBoxFor instead of DropDownListFor:
#Html.ListBoxFor(m => m.branch, CommonMethod.getBranch("", Model.branch), "--Select--")
#Html.ListBoxFor(m => m.division, CommonMethod.getDivision(Model.branch, Model.division), "--Select--")
The branch and division properties must obviously be collections that will contain the selected values.
And a full example of the proper way to build a multiple select dropdown using a view model:
public class MyViewModel
{
public int[] SelectedValues { get; set; }
public IEnumerable<SelectListItem> Values { get; set; }
}
that would be populated in the controller:
public ActionResult Index()
{
var model = new MyViewModel();
// preselect items with values 2 and 4
model.SelectedValues = new[] { 2, 4 };
// the list of available values
model.Values = new[]
{
new SelectListItem { Value = "1", Text = "item 1" },
new SelectListItem { Value = "2", Text = "item 2" },
new SelectListItem { Value = "3", Text = "item 3" },
new SelectListItem { Value = "4", Text = "item 4" },
};
return View(model);
}
and in the view:
#model MyViewModel
...
#Html.ListBoxFor(x => x.SelectedValues, Model.Values)
It is the HTML helper that will automatically preselect the items whose values match those of the SelectedValues property.
For me it works also for #Html.DropDownListFor:
Model:
public class MyViewModel
{
public int[] SelectedValues { get; set; }
public IEnumerable<SelectListItem> Values { get; set; }
}
Controller:
public ActionResult Index()
{
var model = new MyViewModel();
// the list of available values
model.Values = new[]
{
new SelectListItem { Value = "2", Text = "2", Selected = true },
new SelectListItem { Value = "3", Text = "3", Selected = true },
new SelectListItem { Value = "6", Text = "6", Selected = true }
};
return View(model);
}
Razor:
#Html.DropDownListFor(m => m.SelectedValues, Model.Values, new { multiple = "true" })
Submitted SelectedValues in controller looks like:
Though quite old thread but posting this answer after following other answers here, which unfortunately didn't work for me. So, for those who might have stumbled here recently or in near future, Below is what has worked for me.
This is what helped me
The catch for me was MultiSelectList class and I was using SelectList.
Don't know situation in 2012 or 2015. but, now both these helper methods #Html.DropDownListFor and #Html.ListBoxFor helper methods accept IEnumerable<SelectListItem> so you can not pass any random IEnumerable object and expect these helper methods to do the job.
These helper methods now also accept the object of SelectList and MultiSelectList classes in which you can pass the selected values directly while creating there objects.
For example see below code how i created my multi select drop down list.
#Html.DropDownListFor(model => #Model.arrSelectUsers, new MultiSelectList(Model.ListofUsersDTO, "Value", "Text", #Model.arrSelectUsers),
new
{
id = "_ddlUserList",
#class = "form-control multiselect-dropdown",
multiple = "true",
data_placeholder = "Select Users"
})
Related
I have this model:
public class CampoTipoDocumentoViewModel
{
public int TipoDocumentoId { get; set; }
public string[] CamposId { get; set; }
private List<MiddleTier.Models.ICampo> _todosCampos;
public IEnumerable<SelectListItem> TodosCampos
{
get
{
foreach (var campo in _todosCampos)
yield return new SelectListItem { Text = campo.Nombre, Value = campo.Id.ToString() };
}
}
public void SetFields(List<MiddleTier.Models.ICampo> campos)
{
_todosCampos = campos;
}
}
In controller, CamposId property is assigned with elements which has to be selected in the view.
Controller also calls SetFields method populating _todosCampos to the whole list of records in the system.
The idea is to create a View with a SELECT that has initially some records selected.
This is my view:
#Html.DropDownListFor(m => m.CamposId, Model.TodosCampos, new { #class = "form-control", multiple = "multiple", width = "100%" })
The fact is that the HTML SELECT element is created with the list, but no option is selected.
For example, if _todosCampos contains:
Text = "One", Value = "1"
Text = "Two", Value = "2"
Text = "Three", Value = "3"
Text = "Four", Value = "4"
and CamposId contains:
Array of "2", "4"
I need the view to create a SELECT with those 4 options, and option 2 and 4 to be initially selected.
How can I achieve this?
Thanks
Jaime
In order to use <select> element with multiple="multiple" attribute, you need to declare List<string> property:
public List<string> CamposId { get; set; }
And then use ListBoxFor helper instead of DropDownListFor:
#Html.ListBoxFor(m => m.CamposId, Model.TodosCampos, new { #class = "form-control", multiple = "multiple", width = "100%" })
If you want to set some option values are selected by default, then set Selected property into SelectListItem:
public IEnumerable<SelectListItem> TodosCampos
{
get
{
foreach (var campo in _todosCampos)
{
// assumed you have 'campo.IsDefault' which is boolean property
yield return new SelectListItem
{
Text = campo.Nombre,
Value = campo.Id.ToString(),
Selected = campo.IsDefault // set default selected values
};
}
}
}
Note: Usually ID property contain integer values, you can try for List<int> CamposId depending on actual ID data type in database.
I am trying to implement a DropDownList Multi Select using Bootstrap Selectpicker for selecting Schools in my application.
I am not very familiar with MVC and JQuery since i have been using webforms for a long time, so i am learning from internet to accomplish.
Here is the scenario:
on my layout, there is a DropDownList:
#*DropDownList Select School*#
#Html.DropDownList("Schools", null, null, new { id = "MultiSelect", #class = "selectpicker form-control", multiple = "", title = "School" })
The code to fill the DropDownList:
public ActionResult Class()
{
IEnumerable<SelectListItem> ListClasses = db.scasy_class
.OrderBy(a => a.class_name)
.Select(c => new SelectListItem
{
Value = c.id.ToString(),
Text = c.class_name,
Selected = false
});
ViewBag.Class = ListClasses.ToList();
ClassViewModel classViewModel = new ClassViewModel()
{
SelectOptions = ListClasses
};
return View(classViewModel);
}
On layout, when the user selects some schools, using the dropdownlist,
$('#MultiSelect').on('change', function () {
$.each($("#MultiSelect option"), function () {
$.post("/Setup/Student/SetSchool/", { school: $(this).val(), selected: $(this).prop('selected') });
});
});
and the controller;
public ActionResult SetSchool(int school, bool selected)
{
ArrayList school_nos = Session["Schools"] as ArrayList;
if (selected)
{
if (!school_nos.Contains(school))
{
school_nos.Add(school);
}
}
else
{
if (school_nos.Contains(school))
{
school_nos.Remove(school);
}
}
Session["Schools"] = school_nos;
return new HttpStatusCodeResult(HttpStatusCode.OK);
}
it is working as it is expected until here.
For the next reload, i am trying to fill the dropdownlist with the same data but show previously selected schools with tick, using Session values, since i will need this information on many other pages.
$(document).ready(function () {
$.getJSON("/Setup/Student/GetSchool/",
function (data) {
var myData = [];
$.each(data, function (index, item) {
if (item.Selected == true) {
myData.push(item.Value);
}
});
//alert(myData);
$('#MultiSelect').selectpicker('val', myData);
});
});
and the controller;
public JsonResult GetSchool()
{
IEnumerable<SelectListItem> ListSchools = db.scasy_school
.OrderBy(a => a.name)
.Select(a => new SelectListItem { Value = a.id.ToString(), Text = a.name});
ArrayList school_nos = Session["Schools"] as ArrayList;
List<SelectListItem> ListSchoolsUpdated = new List<SelectListItem>();
foreach (var item in ListSchools)
{
SelectListItem selListItem;
if (school_nos.Contains(item.Value.ToString()))
{
selListItem = new SelectListItem() { Value = item.Value.ToString(), Text = item.Text, Selected = true };
}
else
{
selListItem = new SelectListItem() { Value = item.Value.ToString(), Text = item.Text, Selected = false };
}
ListSchoolsUpdated.Add(selListItem);
}
return Json(ListSchoolsUpdated, JsonRequestBehavior.AllowGet);
}
Code throws no error, but i cannot have the dropdownlist with selected items shown.
Declare a model class for your page
public class ClassViewModel {
public List<int> SelectedSchools {get; set;}
public List<SelectListItem> Schools {get; set;}
}
Set Selected Schools in your controller action.
Set Your View Model
#model ClassViewModel
Then in your view use this code to show dropdownlist
#Html.ListBoxFor(m=> m.SelectedSchools , Model.Schools, new {id = "MultiSelect", #class = "selectpicker form-control", title = "School" })
I got two ways to bind my list of values to a dropdown in MVC3. But not sure which is the difference and the best/simpler way to bind.
//Code
public List<SelectListItem> CountryList
{
get
{
return new List<SelectListItem>
{
new SelectListItem { Value = "1", Text = "Bangladesh" },
new SelectListItem { Value = "2", Text = "India" },
new SelectListItem { Value = "3", Text = "Nepal" },
new SelectListItem { Value = "4", Text = "SriLanka" },
};
}
}
(Or)
public SelectList StatusList()
{
List<SelectListItem> lstStatus = new List<SelectListItem>
{
new SelectListItem { Value = "1", Text = "Yes" },
new SelectListItem { Value = "2", Text = "No" },
};
return new SelectList(lstStatus, "Value", "Text", Status);
}
Do i have any advantages/disadvantages in one over another. I have to bind these values and get/set the selected value. Which method will be best one go with?
Kindly suggest.
I tend to use a generic enumeration of SelectListItem in MVC applications. The main reason is that makes more sense when you use ViewModels with your views.
Let's say I have movies stored in a database. I represent a movie with a POCO class.
public class Movie
{
public string Genre { get; set; }
}
The page to edit the movie receive a ViewModel.
public class MovieViewModel
{
public string Genre { get; set; }
public IEnumerable<SelectListItem> GenreList
{
get
{
yield return new SelectListItem { Text = "Comedy", Value = "1" };
yield return new SelectListItem { Text = "Drama", Value = "2" };
yield return new SelectListItem { Text = "Documentary", Value = "3" };
}
}
}
The ViewModel is my model but with additional properties to personalize my view, like the list of the available genres.
Finally in my view, I populate my dropdownlist using the ASP.NET wrapper Html.DropDownListFor().
#model MvcApplication1.Models.MovieViewModel
<!DOCTYPE html>
<html>
<head>
<title>Index</title>
</head>
<body>
<div>
#Html.DropDownListFor(m => m.Genre, Model.GenreList)
</div>
</body>
</html>
The selected value is then automatically chosen using the ViewModel.
I am trying to create a drop down list but it gives me an error saying 'Cannot implicitly convert type 'string' to 'System.Web.Mvc.SelectList'. My code is below:
Application Database Model:
public string dropdown{ get; set; }
Application View Model:
public SelectList dropdown{ get; set; }
ApplicationService.cs:
public static SelectList GetDropdownList(string currSelection)
{
List<SelectListItem> list = new List<SelectListItem>();
list.Add(new SelectListItem { Value = "1", Text = "firstvalue" });
list.Add(new SelectListItem { Value = "2", Text = "secondvalure" });
list.Add(new SelectListItem { Value = "3", Text = "All of the Above" });
return new SelectList(list, "Value", "Text", currSelection);
}
in my controller i am calling:
applicationviewmodel.dropdown= ApplicationService.GetDropdownList(null);
and then trying to save it in database as:
ApplicationDatabaseModel.dropdown= applicationviewmodel.dropdown;
This is where i get this error.
In my view i have:
#Html.DropDownListFor(x => x.dropdown, applicationviewmodel.dropdown)
I am not sure how to make this work.
I find it's easier to just have a List as part of your model and use a simple linq statement. Simple example below for a countries drop down:
assuming you have a model like
public class MyModel()
{
public int CountryId { get; set; }
public List<Country> Countries { get; set; }
}
and a Country class of
public class Country()
{
public int Id { get; set; }
public string Name { get; set; }
}
in your view you can then do the following:
#Html.DropDownListFor(m => m.CountryId,
Model.Countries.Select(x =>
new SelectListItem { Text = x.Name, Value = x.Id.ToString(), Selected = Model.CountryId == x.Id }, "Please Select...", null)
This:
#Html.DropDownListFor(x => x.dropdown, applicationviewmodel.dropdown)
..is incorrect. It is trying to store the selected item into the SelectList instance.
What you want is a string variable on the view model that this value is selected into:
public class ApplicationViewModel {
public SelectList DropDown { get; set; }
public string SelectedDropDownValue { get; set; }
// .. the rest of the properties here
}
Then your view becomes this:
#Html.DropDownListFor(x => x.SelectedDropDownValue, Model.DropDown)
This says "store the selected value into SelectedDropDownValue".
Then, you need to change how you build your SelectList. Value is what gets posted to your property.. Text is what is displayed in the browser.
So this:
list.Add(new SelectListItem { Value = "1", Text = "firstvalue" });
list.Add(new SelectListItem { Value = "2", Text = "secondvalure" });
list.Add(new SelectListItem { Value = "3", Text = "All of the Above" });
..has to be this:
list.Add(new SelectListItem { Value = "firstvalue", Text = "firstvalue" });
list.Add(new SelectListItem { Value = "secondvalue", Text = "secondvalure" });
list.Add(new SelectListItem { Value = "all of the above", Text = "All of the Above" });
..because they are strings (unless of course, you want the numbers to be posted back).
Then, finally, your controller code becomes this:
// assign the string value to the string property
ApplicationDatabaseModel.dropdown = applicationviewmodel.SelectedDropDownValue;
I have a View Model that looks like this:
public class SomeViewModel
{
public SomeViewModel(IEnumerable<SelectListItem> orderTemplatesListItems)
{
OrderTemplateListItems = orderTemplatesListItems;
}
public IEnumerable<SelectListItem> OrderTemplateListItems { get; set; }
}
I then have an Action in my Controller that does this:
public ActionResult Index()
{
var items = _repository.GetTemplates();
var selectList = items.Select(i => new SelectListItem { Text = i.Name, Value = i.Id.ToString() }).ToList();
var viewModel = new SomeViewModel
{
OrderTemplateListItems = selectList
};
return View(viewModel);
}
Lastly my view:
#Html.DropDownListFor(n => n.OrderTemplateListItems, new SelectList(Model.OrderTemplateListItems, "value", "text"), "Please select an order template")
The code works fine and my select list populates wonderfully. Next thing I need to do is set the selected value that will come from a Session["orderTemplateId"] which is set when the user selects a particular option from the list.
Now after looking online the fourth parameter should allow me to set a selected value, so if I do this:
#Html.DropDownListFor(n => n.OrderTemplateListItems, new SelectList(Model.OrderTemplateListItems, "value", "text", 56), "Please select an order template")
56 is the Id of the item that I want selected, but to no avail. I then thought why not do it in the Controller?
As a final attempt I tried building up my select list items in my Controller and then passing the items into the View:
public ActionResult Index()
{
var items = _repository.GetTemplates();
var orderTemplatesList = new List<SelectListItem>();
foreach (var item in items)
{
if (Session["orderTemplateId"] != null)
{
if (item.Id.ToString() == Session["orderTemplateId"].ToString())
{
orderTemplatesList.Add(new SelectListItem { Text = item.Name, Value = item.Id.ToString(), Selected = true });
}
else
{
orderTemplatesList.Add(new SelectListItem { Text = item.Name, Value = item.Id.ToString() });
}
}
else
{
orderTemplatesList.Add(new SelectListItem { Text = item.Name, Value = item.Id.ToString() });
}
}
var viewModel = new SomeViewModel
{
OrderTemplateListItems = orderTemplatesList
};
return View(viewModel);
}
Leaving my View like so:
#Html.DropDownListFor(n => n.OrderTemplateListItems, new SelectList(Model.OrderTemplateListItems, "value", "text"), "Please select an order template")
Nothing!
Why isn't this working for me?
You say "56 is the Id of the item that I want selected, but to no avail"
Should the fourth parameter you refer to be a string, not an integer, like so:
#Html.DropDownListFor(n => n.OrderTemplateListItems, new SelectList(Model.OrderTemplateListItems, "value", "text", "56"), "Please select an order template")