what should be the data format to feed to kendo tree? - asp.net-mvc-3

I'm trying to build a kendo tree menu. I can't figure out what format the data should be feed to the widget. I have tried this so far:
Model:
public class TreeModel
{
public int ID { get; set; }
public string Name { get; set; }
public string URL { get; set; }
public int? ParentsID { get; set; }
public bool HasChild { get; set; }
}
Controller:
public ActionResult LoadMenu()
{
List<TreeModel> list = new List<TreeModel> {
new TreeModel() { ID=1, Name="Setup", URL="m.facebook.com", HasChild=true},
new TreeModel() { ID=10, Name="Leave", URL="google.com", ParentsID=1, HasChild=false},
new TreeModel() { ID=2, Name="EmployeeInfo", URL="m.facebook.com", HasChild=true},
new TreeModel() { ID=11, Name="Basic Employee", URL="m.facebook.com", HasChild=false, ParentsID=2},
};
var nodes = (from n in list
where n.HasChild == true
select n).ToList();
return Json(nodes, JsonRequestBehavior.AllowGet);
}
Script on my view:
<script type="text/javascript">
homogeneous = new kendo.data.HierarchicalDataSource({
transport: {
read: {
url: "/Home/LoadMenu",
//dataType: "json",
type: "GET"
}
},
schema: {
model: {
id: "ID",
hasChildren: "HasChild"
}
}
});
$(document).ready(function () {
$("#treeMenu").kendoTreeView({
dataSource: homogeneous,
dataTextField: "Name",
dataUrlField: "URL",
hasChildren:"ParentsID"
});
});
</script>
The current output & problems are marked on the screen shot.
please help. Thanks.

Please try with the below code snippet.
public ActionResult LoadMenu(int? id)
{
List<TreeModel> list = new List<TreeModel> {
new TreeModel() { ID=1, Name="Setup", URL="m.facebook.com", HasChild=true},
new TreeModel() { ID=10, Name="Leave", URL="google.com", ParentsID=1, HasChild=false},
new TreeModel() { ID=2, Name="EmployeeInfo", URL="m.facebook.com", HasChild=true},
new TreeModel() { ID=11, Name="Basic Employee", URL="m.facebook.com", HasChild=false, ParentsID=2},
};
var nodes = (from n in list
where (id.HasValue ? n.ParentsID == id.Value : n.ParentsID == null)
select n).ToList();
return Json(nodes, JsonRequestBehavior.AllowGet);
}

Related

ASP.NET MVC passing data to partial view through ajax

I am using full calendar library, where I load my events as JSON and display them in the calendar.
What I would like to do next is to load an id of the latest event and display information about the event from the model in the partial view. This is my code so far:
<div id="calendar"></div>
<div id="myPartial"></div>
<script>
$('#calendar').fullCalendar({
aspectRatio: 3,
events: function (start, end, timezone, callback) {
$.getJSON("#Url.Action("GetEvents")", function (locationsArray) {
var result = $(locationsArray).map(function () {
return {
id: this.idEvent,
title: this.eventName,
start: this.startTime,
end: this.endTime,
allDay: this.allDay
};
}).toArray();
callback(result);
var id_latest = result[result.length - 1].id
success: $(function (id_latest) {
$.ajax({
type: "POST",
url: '#Url.Action("AddContent","Home")',
data: { id: id_latest },
error: function () {
alert("An error occurred.");
},
success: function (data) {
$("#myPartial").html(data);
}
});
});
});
}
});
</script>
What am I missing here? What is the proper way to do it?
Edit:
Controller:
namespace bezeckaApp.Controllers
{
public class HomeController : Controller
{
// GET: Home
public ActionResult Index()
{
return View();
}
public ActionResult AddContent(int? id)
{
return PartialView("~/Views/Home/AddContent.cshtml");
}
public ActionResult GetEvents()
{
List<Treninky> trenink = new List<Treninky>();
trenink.Add(new Treninky() { idEvent = 1, eventName = "Morning run", startTime = "2017-07-01T08:00:00Z", endTime = "2017-07-01T09:00:00", allDay = false });
trenink.Add(new Treninky() { idEvent = 2, eventName = "Evening run", startTime = "2017-07-05T17:00:00Z", endTime = "2017-07-05T18:00:00", allDay = false });
trenink.Add(new Treninky() { idEvent = 3, eventName = "Evening run", startTime = "2017-07-08T17:00:00Z", endTime = "2017-07-08T18:00:00", allDay = false });
return Json(trenink, JsonRequestBehavior.AllowGet);
}
}
}
Model:
namespace bezeckaApp.Models
{
public class Treninky
{
public int idEvent { set; get; }
public string eventName { set; get; }
public string startTime { set; get; }
public string endTime { set; get; }
public bool allDay { set; get; }
}
}
EDIT
this still causes id in AddContent method NULL
public ActionResult AddContent(int? id)
{
List<Treninky> trenink = new List<Treninky>();
trenink.Add(new Treninky() { idEvent = 1, eventName = "Morning run", startTime = "2017-07-01T08:00:00Z", endTime = "2017-07-01T09:00:00", allDay = false });
trenink.Add(new Treninky() { idEvent = 2, eventName = "Evening run", startTime = "2017-07-05T17:00:00Z", endTime = "2017-07-05T18:00:00", allDay = false });
trenink.Add(new Treninky() { idEvent = 3, eventName = "Evening run", startTime = "2017-07-08T17:00:00Z", endTime = "2017-07-08T18:00:00", allDay = false });
return PartialView("~/Views/Home/AddContent.cshtml",trenink.Find(id));
}
If yours javascript is working, and you getting latest ID then it should work.

Recommended way to implement array of Ajax cascading dropdown lists in MVC4/Razor?

I am writing an ASP.NET MVC4 / Razor / C# based application that needs to render a grid of records. Each row has several columns, and there may be 100 or so rows.
Each row has a checkbox field, text field and then three cascading dropdown lists. The first dropdown is prepopulated on page load. The second needs to be populated using Ajax on change of the first dropdown list. The third from a change on the second. Each row is separate and does not influence each other.
What is the recommended way to implement something like this? The various solutions for cascading dropdown lists are only for single cascading lists - they do not work (for me) when placed inside a foreach loop.
The skeleton of what I have is shown below:
#model IList<MyModel>
#using (Html.BeginForm("MyAction", "Home")) {
<table><tr><th>Use?</th><th>Name</th><th>List A</th><th>List B</th><th>List C</th></tr>
#Html.EditorForModel()
</table>
}
The model looks something like this:
public class MyModel
{
public bool Use { get; set; }
public string Name { get; set; }
public int? ListAId { get; set; }
public int? ListBId { get; set; }
public int? ListCId { get; set; }
public IList<ListAList> ListA { get; set; }
}
The shared EditorTemplates file MyModel.cshtml follows this structure:
#model MyNamespace.MyModel
<tr>
<td>#Html.CheckBoxFor(model => model.Use)</td>
<td>#Html.DisplayFor(model => model.Name)</td>
<td>#Html.DropDownListFor(model => model.ListAId, new SelectList(Model.ListA, "Id", "Name", Model.ListAId), "")</td>
<td>??</td>
<td>??</td>
</tr>
The ?? indicates I am unsure what to put in here.
How do I proceed to render the ListB select box using Ajax on change of the ListA select box, then on change of ListB render the ListC select box?
check this:
on select change event - Html.DropDownListFor
http://addinit.com/node/19
or
http://www.codeproject.com/Articles/258172/Simple-Implementation-of-MVC-Cascading-Ajax-Drop-D
Update1: Suppose that there is Name ROWID, (and list all the same data source).
Update2: the example available on github
Based on these responses:
How to populate a #html.dropdownlist mvc helper using JSon
Populate a <select></select> box with another
Model:
using System.Collections.Generic;
namespace MyNamespace
{
public class MyModel
{
public MyModel() { ListA = new List<ListAList>(); }
public bool Use { get; set; }
public string Name { get; set; }
public int? ListAId { get; set; }
public int? ListBId { get; set; }
public int? ListCId { get; set; }
public IList<ListAList> ListA { get; set; }
}
public class ListAList
{
public int Id { get; set; }
public string Name { get; set; }
}
}
Main action in the Home Controller:
public ViewResult MyAction()
{
var model = new List<MyModel>();
for (int i = 0; i < 10; i++)
{
var item = new MyModel()
{
Name = string.Format("Name{0}", i),
Use = (i % 2 == 0),
ListAId = null,
ListBId = null,
ListCId = null
};
for (int j = 0; j < 10; j++)
{
item.ListA.Add( new ListAList()
{
Id=j,
Name = string.Format("Name {0}-{1}",i,j)
});
}
model.Add(item);
}
return View(model);
}
Data source provider in the Home controller:
public JsonResult PopulateOption(int? listid, string name)
{
//todo: preparing the data source filter
var sites = new[]
{
new { id = "1", name = "Name 1" },
new { id = "2", name = "Name 2" },
new { id = "3", name = "Name 3" },
};
return Json(sites, JsonRequestBehavior.AllowGet);
}
EditorTemplate:
#model MyNamespace.MyModel
<tr>
<td>#Html.CheckBoxFor(model => model.Use)</td>
<td>#Html.DisplayFor(model => model.Name)</td>
<td>#Html.DropDownListFor(model => model.ListAId, new SelectList(Model.ListA, "Id", "Name", Model.ListAId), "", new { #id = string.Format("ListA{0}", Model.Name), #class="ajaxlistA" })</td>
<td><select class="ajaxlistB" id="ListB#(Model.Name)"></select></td>
<td><select class="ajaxlistC" id="ListC#(Model.Name)"></select></td>
</tr>
And the main view with Ajax functions:
#using MyNamespace
#model IList<MyModel>
#using (Html.BeginForm("MyAction", "Home")) {
<table><tr><th>Use?</th><th>Name</th><th>List A</th><th>List B</th><th>List C</th></tr>
#Html.EditorForModel()
</table>
}
<script src="#Url.Content("~/Scripts/jquery-1.7.1.js")" type="text/javascript"></script>
<script>
$(document).ready( $(function () {
$('.ajaxlistA').change(function () {
// when the value of the first select changes trigger an ajax request
list = $(this);
var listvalue = list.val();
var listname = list.attr('id');
$.getJSON('#Url.Action("PopulateOption", "Home")', { listid: listvalue, name: listname }, function (result) {
// assuming the server returned json update the contents of the
// second selectbox
var listB = $('#' + listname).parent().parent().find('.ajaxlistB');
listB.empty();
$.each(result, function (index, item) {
listB.append(
$('<option/>', {
value: item.id,
text: item.name
})
);
});
});
});
$('.ajaxlistB').change(function () {
// when the value of the first select changes trigger an ajax request
list = $(this);
var listvalue = list.val();
var listname = list.attr('id');
$.getJSON('#Url.Action("PopulateOption", "Home")', { listid: listvalue, name: listname }, function (result) {
// assuming the server returned json update the contents of the
// second selectbox
var listB = $('#' + listname).parent().parent().find('.ajaxlistC');
listB.empty();
$.each(result, function (index, item) {
listB.append(
$('<option/>', {
value: item.id,
text: item.name
})
);
});
});
});
}));
</script>
And the result:

Unobtrusive validation of collection

My model contains a collection:
public ICollection<int> ChildAges { get; set; }
This is a dynamic list of ages that can be added to, this is all controlled via JQuery.
giving me
<select name="ChildAges">...</select>
<select name="ChildAges">...</select>
<select name="ChildAges">...</select>
etc...
If I add the standard Required attribute the validation returns true if any one value in the collection is set.
How can I validate that all ChildAges in the form are set?
I created a new custom IClientValidatable attribute:
[AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
public class MultipleRequiredValuesAttribute : RequiredAttribute, IClientValidatable
{
#region IClientValidatable Members
public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
{
var clientValidationRule = new ModelClientValidationRule()
{
ErrorMessage = base.ErrorMessage,
ValidationType = "multiplerequiredvalues"
};
return new[] { clientValidationRule };
}
#endregion
}
and applied this to my model:
[DisplayName("Ages(s)")]
[MultipleRequiredValues(ErrorMessage = "You must provide ages for all children in all rooms")]
public ICollection<int> ChildAges { get; set; }
I can then add the JQuery side:
(function ($) {
$.validator.addMethod('multiplerequiredvalues', function (value, element) {
if ($(element).is(':visible')) {
var returnVal = true;
var name = $(element).attr('name');
var elements;
if ($(element).is('input')) {
elements= $('input[name='+name+']');
}
else
{
elements= $('select[name='+name+']');
}
elements.each(function() {
if ($(this).is(':visible'))
{
returnVal = $(this).val() != "" && $(this).val() != null;
}
});
return returnVal;
}
else {
return true;
}
});
$.validator.unobtrusive.adapters.addBool("multiplerequiredvalues");
} (jQuery));
Note this also returns true if the element isn't visible

Problems with MVC 3 DropDownList() in WebGrid()

I'm trying to place a DropDownList inside a WebGrid but I can't figure out how to do it :(
Things I've tried:
grid.Column("Id", "Value", format: ((item) =>
Html.DropDownListFor(item.SelectedValue, item.Colors)))
and
grid.Column(header: "", format: (item => Html.DropDownList("Colors", item.Colors)))
and
grid.Column(header: "", format: Html.DropDownList("Colors"))
and various others but I couldn't get it to work.
Any help is much appreciated.
Model
public class PersonViewModel
{
public string Name { get; set; }
public int Age { get; set; }
public SelectList Colors { get; set; }
public int SelectedValue { get; set; }
}
public class ColorViewModel
{
public int ColorID { get; set; }
public string ColorName { get; set; }
}
Controller
public ActionResult Index()
{
var colorList = new List<ColorViewModel>() {
new ColorViewModel() { ColorID = 1, ColorName = "Green" },
new ColorViewModel() { ColorID = 2, ColorName = "Red" },
new ColorViewModel() { ColorID = 3, ColorName = "Yellow" }
};
var people = new List<PersonViewModel>()
{
new PersonViewModel() {
Name = "Foo",
Age = 42,
Colors = new SelectList(colorList)
},
new PersonViewModel() {
Name = "Bar",
Age = 1337,
Colors = new SelectList(colorList)
}
};
return View(people);
}
View
#model IEnumerable<PersonViewModel>
#{
var grid = new WebGrid(Model);
}
<h2>DropDownList in WebGrid</h2>
#using (Html.BeginForm())
{
#grid.GetHtml(
columns: grid.Columns(
grid.Column("Name"),
grid.Column("Age"),
grid.Column() // HELP - INSERT DROPDOWNLIST
)
)
<p>
<button>Submit</button>
</p>
}
grid.Column(
"dropdown",
format: #<span>#Html.DropDownList("Color", (SelectList)item.Colors)</span>
)
Also in your controller make sure you set the value and text properties of your SelectList and instead of:
Colors = new SelectList(colorList)
you should use:
Colors = new SelectList(colorList, "ColorID", "ColorName")
Also it seems a bit wasteful to me to define the same SelectList for all row items especially if they contain the same values. I would refactor your view models a bit:
public class MyViewModel
{
public IEnumerable<SelectListItem> Colors { get; set; }
public IEnumerable<PersonViewModel> People { get; set; }
}
public class PersonViewModel
{
public string Name { get; set; }
public int Age { get; set; }
public int SelectedValue { get; set; }
}
and then:
public class HomeController : Controller
{
public ActionResult Index()
{
var model = new MyViewModel
{
// define the values used to render the dropdown lists
// for each row
Colors = new[]
{
new SelectListItem { Value = "1", Text = "Green" },
new SelectListItem { Value = "2", Text = "Red" },
new SelectListItem { Value = "3", Text = "Yellow" },
},
// this is the collection we will be binding the WebGrid to
People = new[]
{
new PersonViewModel { Name = "Foo", Age = 42 },
new PersonViewModel { Name = "Bar", Age = 1337 },
}
};
return View(model);
}
}
and in the view:
#model MyViewModel
#{
var grid = new WebGrid(Model.People);
}
<h2>DropDownList in WebGrid</h2>
#using (Html.BeginForm())
{
#grid.GetHtml(
columns: grid.Columns(
grid.Column("Name"),
grid.Column("Age"),
grid.Column(
"dropdown",
format: #<span>#Html.DropDownList("Color", Model.Colors)</span>
)
)
)
<p>
<button>Submit</button>
</p>
}
UPDATE:
And since I suspect that you are not putting those dropdownlists for painting and fun in your views but you expect the user to select values inside them and when he submits the form you might wish to fetch the selected values, you will need to generate proper names of those dropdown lists so that the default model binder can automatically retrieve the selected values in your POST action. Unfortunately since the WebGrid helper kinda sucks and doesn't allow you to retrieve the current row index, you could use a hack as the Haacked showed in his blog post:
grid.Column(
"dropdown",
format:
#<span>
#{ var index = Guid.NewGuid().ToString(); }
#Html.Hidden("People.Index", index)
#Html.DropDownList("People[" + index + "].SelectedValue", Model.Colors)
</span>
)
Now you could have a POST controller action in which you will fetch the selected value for each row when the form is submitted:
[HttpPost]
public ActionResult Index(MyViewModel model)
{
// the model variable will contain the People collection
// automatically bound for each row containing the selected value
...
}
..make my dropdown list to select a value from the list when it loads.The following works for sure. I have tried it out myself. Any questions keep me posted.
#Html.DropDownList("RejectReason", Model.SalesReasonList.Select(u => new SelectListItem
{
Text = u.Text,
Value = u.Value,
Selected = u.Value ==#item.RejectReason
}))

Populating child drop down based on what was selected from parent drop down list

I am using the latest version of jQuery and ASP.NET MVC 3 with the Razor view engine.
I have tried Google looking for a decent example of loading a child drop down list when a parent drop down item is selected. I am looking to do this via jQuery AJAX using JSON. My knowledge of this is zero.
I have a Category class with a list of categories. It's a parent-child association.
If I select a category from the parent drop down list, then all the child categories need to be listed in the child drop down list for the selected parent category.
This is what I currently have, but need to complete it, not sure if I am in the right direction:
$(document).ready(function () {
$('#ddlParentCategories').change(function () {
alert('changed');
});
});
I loaded my drop down list from my view model as such:
#Html.DropDownListFor(x => x.ParentCategoryId, new SelectList(Model.ParentCategories, "Id", "Name", Model.ParentCategoryId), "-- Select --", new { id = "ddlParentCategories" })
The first item has text "-- Select --" (for both parent and child drop down lists). On initial page load nothing must be loaded in the child drop down list. When a value is selected then the child drop down list must be populated. And when "-- Select --" is selected again in the parent drop down list then all the items in the child drop down list must cleared except "-- Select --".
If possible, if the child categories is loading, how do I display that "round" loading icon?
UPDATE
I have updated my code to Darin's code, and I cannot get it to work properly:
Category class:
public class Category
{
public int Id { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public string MetaKeywords { get; set; }
public string MetaDescription { get; set; }
public bool IsActive { get; set; }
public int? ParentCategoryId { get; set; }
public virtual Category ParentCategory { get; set; }
public virtual ICollection<Category> ChildCategories { get; set; }
}
EditProductViewModel class:
public class EditProductViewModel
{
public int Id { get; set; }
public string Name { get; set; }
public string ShortDescription { get; set; }
public string LongDescription { get; set; }
public bool IsActive { get; set; }
public string PageTitle { get; set; }
public bool OverridePageTitle { get; set; }
public string MetaKeywords { get; set; }
public string MetaDescription { get; set; }
public int ParentCategoryId { get; set; }
public IEnumerable<Category> ParentCategories { get; set; }
public int ChildCategoryId { get; set; }
public IEnumerable<Category> ChildCategories { get; set; }
}
ProductController class:
public ActionResult Create()
{
EditProductViewModel viewModel = new EditProductViewModel
{
ParentCategories = categoryService.GetParentCategories()
.Where(x => x.IsActive)
.OrderBy(x => x.Name),
ChildCategories = Enumerable.Empty<Category>(),
IsActive = true
};
return View(viewModel);
}
public ActionResult AjaxBindingChildCategories(int parentCategoryId)
{
IEnumerable<Category> childCategoryList = categoryService.GetChildCategoriesByParentCategoryId(parentCategoryId);
return Json(childCategoryList, JsonRequestBehavior.AllowGet);
}
Create view:
<tr>
<td><label>Parent Category:</label> <span class="red">*</span></td>
<td>#Html.DropDownListFor(x => x.ParentCategoryId,
new SelectList(Model.ParentCategories, "Id", "Name", Model.ParentCategoryId),
"-- Select --",
new { data_url = Url.Action("AjaxBindingChildCategories"), id = "ParentCategories" }
)
#Html.ValidationMessageFor(x => x.ParentCategoryId)
</td>
</tr>
<tr>
<td><label>Child Category:</label> <span class="red">*</span></td>
<td>#Html.DropDownListFor(x => x.ChildCategoryId,
new SelectList(Model.ChildCategories, "Id", "Name", Model.ChildCategoryId),
"-- Select --",
new { id = "ChildCategories" }
)
#Html.ValidationMessageFor(x => x.ChildCategoryId)
</td>
</tr>
<script type="text/javascript">
$(document).ready(function () {
$('#ParentCategories').change(function () {
var url = $(this).data('url');
var data = { parentCategoryId: $(this).val() };
$.getJSON(url, data, function (childCategories) {
var childCategoriesDdl = $('#ChildCategories');
childCategoriesDdl.empty();
$.each(childCategories, function (index, childCategory) {
childCategoriesDdl.append($('<option/>', {
value: childCategory, text: childCategory
}));
});
});
});
});
</script>
It goes into my AjaxBindingChildCategories action and it brings back records, it just doesn't want to display my child category dropdownlist. I had a look in Fire Bug and the error that I get is:
GET AjaxBindingChildCategories?parentCategoryId=1
500 Internal Server Error
Here's an example of cascading drop down lists. As always start by defining a view model:
public class MyViewModel
{
[DisplayName("Country")]
[Required]
public string CountryCode { get; set; }
public IEnumerable<SelectListItem> Countries { get; set; }
public string City { get; set; }
public IEnumerable<SelectListItem> Cities { get; set; }
}
then a controller:
public class HomeController : Controller
{
public ActionResult Index()
{
var model = new MyViewModel
{
// TODO: Fetch countries from somewhere
Countries = new[]
{
new SelectListItem { Value = "FR", Text = "France" },
new SelectListItem { Value = "US", Text = "USA" },
},
// initially we set the cities ddl to empty
Cities = Enumerable.Empty<SelectListItem>()
};
return View(model);
}
public ActionResult Cities(string countryCode)
{
// TODO: based on the selected country return the cities:
var cities = new[]
{
"Paris", "Marseille", "Lyon"
};
return Json(cities, JsonRequestBehavior.AllowGet);
}
}
a view:
#model MyViewModel
#using (Html.BeginForm())
{
<div>
#Html.LabelFor(x => x.CountryCode)
#Html.DropDownListFor(
x => x.CountryCode,
Model.Countries,
"-- Select country --",
new { data_url = Url.Action("cities") }
)
#Html.ValidationMessageFor(x => x.CountryCode)
</div>
<div>
#Html.LabelFor(x => x.City)
#Html.DropDownListFor(
x => x.City,
Model.Cities,
"-- Select city --"
)
#Html.ValidationMessageFor(x => x.City)
</div>
<p><input type="submit" value="OK" /></p>
}
and finally the unobtrusive javascript in a separate file:
$(function () {
$('#CountryCode').change(function () {
var url = $(this).data('url');
var data = { countryCode: $(this).val() };
$.getJSON(url, data, function (cities) {
var citiesDdl = $('#City');
citiesDdl.empty();
$.each(cities, function (index, city) {
citiesDdl.append($('<option/>', {
value: city,
text: city
}));
});
});
});
});
jQuery script will look like this:
<script type="text/javascript">
function getCities(abbr) {
$.ajax({
url: "#Url.Action("Cities", "Locations")",
data: {abbreviation: abbr},
dataType: "json",
type: "POST",
error: function() {
alert("An error occurred.");
},
success: function(data) {
var items = "";
$.each(data, function(i, item) {
items += "<option value=\"" + item.Value + "\">" + item.Text + "</option>";
});
$("#City").html(items);
}
});
}
$(document).ready(function(){
$("#State").change(function() {
var abbr = $("#State").val();
getCities(abbr);
});
});
</script>
A repository to retrieve data could look like this (obviously hook it up to live data though):
public class LocationRepository : ILocationRepository
{
public IQueryable<State> GetStates()
{
return new List<State>
{
new State { Abbreviation = "NE", Name = "Nebraska" },
new State { Abbreviation = "NC", Name = "North Carolina" }
}.AsQueryable();
}
public IQueryable<City> GetCities(string abbreviation)
{
var cities = new List<City>();
if (abbreviation == "NE")
{
cities.AddRange(new List<City> {
new City { Id = 1, Name = "Omaha" },
new City { Id = 2, Name = "Lincoln" }
});
}
else if (abbreviation == "NC")
{
cities.AddRange(new List<City> {
new City { Id = 3, Name = "Charlotte" },
new City { Id = 4, Name = "Raleigh" }
});
}
return cities.AsQueryable();
}
}
public interface ILocationRepository
{
IQueryable<State> GetStates();
IQueryable<City> GetCities(string abbreviation);
}
Controllers could look like this:
public class LocationsController : Controller
{
private ILocationRepository locationRepository = new LocationRepository();
[HttpPost]
public ActionResult States()
{
var states = locationRepository.GetStates();
return Json(new SelectList(state, "Id", "Name"));
}
[HttpPost]
public ActionResult Cities(string abbreviation)
{
var cities = locationRepository.GetCities(abbreviation);
return Json(new SelectList(cities, "Abbreviation", "Name"));
}
}
I am assuming you populate the parent dropdown from server side and also the first option in this parent dd is "--- Select ---"
You can try this
$(document).ready(function () {
var $parent = $('#ddlParentCategories');
var $child = $('#ddlChildCategories');
$child.find("option:gt(0)").remove();
if(!$parent.children().eq(0).is(":selected")){
$parent.change(function () {
$.ajax({
url: "urlToFetchTheChild",
data: { categoryId: this.value },
success: function(data){
//The data you send should be a well formed array of json object containing code/value pair of child categories
for(var i = 0;i<data.length;i++){
$child.append("<option value='"+ data[i].code +"'>"+ data[i].value +"</option>");
}
}
});
});
}
});

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