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Reload page based on a selection from drop down list MVC

I have a working solution, but I don't know how to reload the page after a certain ID is selected from the drop down list. My list is being populated from the DB. When I select it, I can see the ID and the corresponding data for it. However, there is no change on the screen.
Model class:
public List<Hello> getID()
{
var que = (from rel in db.Table1
select new Hello
{
ID = rel.R_ID
}).ToList();
return que;
}
public List<Hello> getStuff()
{
var que = (from wre in db.View
select new Hello
{
ID = wre.R_ID,
Summary = wre.Summary,
Description = wre.Description
}
}
getHello() is the same exact method as the getStuff(), just accepts a string ID parameter.
Controller class:
public ActionResult Index()
{
var model = test.getStuff();
ViewBag.IDs = new SelectList(test.getID(), "", "ID");
return View(model);
}
[HttpPost]
public JsonResult getDataBySelectedID(string selectedId)
{
var que = test.getHello(selectedId);
return Json(que, JsonRequestBehavior.AllowGet);
}
Partial_View Class:
<div class="container">
<table id="myTable" align="left">
<tr>
<th>#Html.DisplayNameFor(model => model.R_ID)</th>
<th>#Html.DisplayNameFor(model => model.Summary)</th>
<th>#Html.DisplayNameFor(model => model.Description)</th>
</tr>
#foreach (var item in Model)
{
<tr id="Home">
<td>#Html.DisplayFor(x => item.R_ID)</td>
<td>#Html.DisplayFor(x => item.Summary)</td>
<td>#Html.DisplayFor(x => item.Description)</td>
</tr>
}
</table>
</div>
View Class:
#Html.DropDownList("ID", ViewBag.IDs as SelectList)
<script>
$(document).ready(function () {
$("#ID").on("change", function () {
var selectedId = this.value;
var url = "/Sample/getDataBySelectedID";
$.ajax({
method: "POST",
dataType: "json",
url: url,
data: {
selectedId: selectedId
}
});
});
});
</script>
#foreach (var item in Model)
{
<tr>
<td>
#{Html.RenderPartial("Partial_Index", item);}
</td>
</tr>
}
How would I be able to reload the page with the selected value and its corresponding data?
Any help would be appreciated!
Thank you.

As described in the comments, you'll have to load your data into your page somehow. I recommend you do this through partial views.
1) Create a reusable Partial View
First, create a partial view that references your model. To do this, create a view as you normally would for your controller, and tick the "Partial View" option. Make sure to select your model in the model dropdown.
Then, move your .cshtml that references your model from your current view to your partial view. For example, if you have a table that lists out the fields of your model, you would cut the entire table into your partial view. You want to include the minimal amount of code needed in the partial view (aka, don't copy your entire view into it).
2) Reference the Partial View in your Current View
Now that you have your partial view set up, you should use it in your existing view to load the table. You should make sure this works first before continuing. You can use the #Html.RenderPartial(string ViewName, object Model) helper method to render it. Read more. So, you might place this line where your now-cut-code was: #RenderPartial("MyPartialView", model), where "MyPartialView" is the name of your partial view, and model is the model object that you want to pass into the partial view.
3) Add Methods to Render Partial View on Controller
At this point, you just need to be able to update your partial view after using AJAX. First, you need to add the ability to render the Partial View as a string so that you can easily inject it into your view. I recommend you do this by implementing a controller interface and letting your controller inherit the needed methods from that. In my programs, I have the following controller interface that my controllers inherit from:
public class IBaseController : Controller
{
internal string PartialViewToString(string partialViewName, object model = null)
{
ControllerContext controllerContext = new ControllerContext(Request.RequestContext, this);
return ViewToString(
controllerContext,
ViewEngines.Engines.FindPartialView(controllerContext, partialViewName) ?? throw new FileNotFoundException("Partial view cannot be found."),
model
);
}
protected string ViewToString(string viewName, object model = null)
{
ControllerContext controllerContext = new ControllerContext(Request.RequestContext, this);
return ViewToString(
controllerContext,
ViewEngines.Engines.FindView(controllerContext, viewName, null) ?? throw new FileNotFoundException("View cannot be found."),
model
);
}
protected string ViewToString(string viewName, string controllerName, string areaName, object model = null)
{
RouteData routeData = new RouteData();
routeData.Values.Add("controller", controllerName);
if (areaName != null)
{
routeData.Values.Add("Area", areaName);
routeData.DataTokens["area"] = areaName;
}
ControllerContext controllerContext = new ControllerContext(HttpContext, routeData, this);
return ViewToString(
controllerContext,
ViewEngines.Engines.FindView(controllerContext, viewName, null) ?? throw new FileNotFoundException("View cannot be found."),
model
);
}
private string ViewToString(ControllerContext controllerContext, ViewEngineResult viewEngineResult, object model)
{
using (StringWriter writer = new StringWriter())
{
ViewContext viewContext = new ViewContext(
ControllerContext,
viewEngineResult.View,
new ViewDataDictionary(model),
new TempDataDictionary(),
writer
);
viewEngineResult.View.Render(viewContext, writer);
return writer.ToString();
}
}
}
Then, on your controller you can inherit from this interface like so:
public class ExampleController : IBaseController
{
}
Now, you can use the new methods to easily render your partial view to a string.
In your getDataBySelectedID action, this is what you'll want to do.
[HttpPost]
public JsonResult getDataBySelectedID(string selectedId)
{
var que = test.getHello(selectedId);
string partialViewString = PartialViewToString("MyPartialView", que);
return Json(partialViewString, JsonRequestBehavior.AllowGet);
}
You may need to modify the above statement to fit your uses, but it should get you close.
4) Inject Partial View into Page on AJAX Success
Now, we've setup a Partial View to handle the model data that we want to update. We've updated our view to load from the Partial View by default. We've implemented a controller interface that will let use render that Partial View to a string so that we can inject it into our page. Now, we just need to do that injection.
First, wrap the previous setup #Html.RenderPartial() statement in a div. Let's give it the ID partialViewDiv. This will let us easily target it with jQuery.
$(document).ready(function () {
$("#ID").on("change", function () {
var selectedId = this.value;
var url = "/Sample/getDataBySelectedID";
var $partialViewDiv = $('#partialViewDiv');
$.ajax({
method: "POST",
dataType: "json",
url: url,
data: {
selectedId: selectedId
}
})
.done(function (response, status, jqxhr) {
$partialViewDiv.html(response);
// Do any other updates here.
})
.fail(function (reponse, status, error) {
$partialViewDiv.html('');
// Handle your error here.
});
});
});
Again, these is mostly pseudo-code so you may have to make some modifications. But, at this point, you should be roughly where you need to be. The AJAX call should update your view by reloading the partial view with your new model data.
Tips
Loading a partial view like this may break some jQuery event handlers, depending on your application. If that happens, take a look at this.
You can return any string from the Controller with your AJAX call. You could, if needed, return different partial views than what you originally loaded. Just use the methods from the interface and you can render whatever you need.
The above code is only some general guidelines. Without knowing your full implementation, I can't provide 100% working, bug free code. But, post here if you have any issues and I'll try to help.

A solution i see is with php
location.reload();
That is how you reload but if you want to reload with data you could use something like
window.location.replace("PathToThePage.php?YourDataName=YourData");

How to use DevExtreme in partial view (ASP.NET MVC)?

I try to use DevExtreme component in partial view.
But my partial view page shown when I click on the element.
And in the main page after the click I have error
Newtonsoft.Json.JsonSerializationException: Self referencing loop detected for property 'ApplicationEntity' with type 'System.Data.Entity.DynamicProxies.ApplicationEntity_50A6A66F1464C1DE4E8A736E85D88C5AF4F4249EAE26FB21C4F82592E001885D'. Path 'data[0].ApplicationEntity.ApplicationEntityHistories[0]'.
browser console screen
Main page Code:
<div class="row">
<div class="col-md-7">
<button id="btn">CLICK</button
</div>
<div class="col-md-5" id="divPartialViewContainer">
</div>
</div>
<script>
$(document).ready(function () {
$("#btn").on("click", function () {
var text = $(this).text().trim();
if (text.length > 0) {
console.log(text);
$.ajax({
url: '/RiskMap/RiskDetailsPartial/',
type: 'POST',
contentType: 'application/json',
data: JSON.stringify({ 'param': text }),
success: function (content) {
$('#divPartialViewContainer').html(content);
},
error: function (e)
{
console.log(e);
}
});
}
});
});
</script>
Controller Code
[HttpPost]
public async Task<ActionResult> RiskDetailsPartial(string param)
{
return PartialView("_RiskDetails", new List<Risk>());
}
Partial View code:
#model IEnumerable<Core.Models.Risk>
#using Core.Models
#using Core.ComplexTypes
#{
ViewBag.Title = "Risks";
}
<h2>Risks</h2>
#(Html.DevExtreme().DataGrid<Risk>()
.DataSource(Model)
.Columns(columns =>
{
columns.AddFor(m => m.Id);
columns.AddFor(m => m.Impact);
columns.AddFor(m => m.Probability);
})
)

The message is clear you just need to read it more thoroughly.
Newtonsoft.Json.JsonSerializationException: Self referencing loop
detected for property 'ApplicationEntity' with type
'System.Data.Entity.DynamicProxies.ApplicationEntity_50A6A66F1464C1DE4E8A736E85D88C5AF4F4249EAE26FB21C4F82592E001885D'.
Path 'data[0].ApplicationEntity.ApplicationEntityHistories[0]'.
Json serializer is attempting to serialize some kind of entity(lets call it EntityA) you passed to it, but the problem is that this entity contains another entity(lets call it EntityB) that contains the first entity(EntityA). This is going in circles!
This has also happened to me with my own ORM and I found out the problem is lazy loading. I solved it by adding an interface to each of my entities:
interface IJSonify
{
object Json();
}
Here I simply return an anonymous object. Entity that implements this interface decides how it will represent itself as JSON object.

I had the same problem and I solved it by declaring JsonConvert defaultSettings on webApplication init.
JsonConvert.DefaultSettings = () => new JsonSerializerSettings
{
Formatting = Newtonsoft.Json.Formatting.Indented,
ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore
};
Apparently DevExtreme don't use standard ASP.NET MVC json serializer inside DataSourceLoader.Load(..) method, so if you set ASP.NET MVC json serializer ReferenceLoopHandling setting it is not enough.
Another solution is use [JsonIgnore] dataAnnotation above the property that generate the loop reference

How do I populate a list field in a model from javascript?

I have a Kendo.MVC project. The view has a model with a field of type List<>. I want to populate the List from a Javascript function. I've tried several ways, but can't get it working. Can someone explain what I'm doing wrong?
So here is my model:
public class Dashboard
{
public List<Note> ListNotes { get; set; }
}
I use the ListNotes on the view like this:
foreach (Note note in Model.ListNotes)
{
#Html.Raw(note.NoteText)
}
This works if I populate Model.ListNotes in the controller when the view starts...
public ActionResult DashBoard(string xsr, string vst)
{
var notes = rep.GetNotesByCompanyID(user.ResID, 7, 7);
List<Koorsen.Models.Note> listNotes = new List<Koorsen.Models.Note>();
Dashboard employee = new Dashboard
{
ResID = intUser,
Type = intType,
FirstName = user.FirstName,
LastName = user.LastName,
ListNotes = listNotes
};
return View(employee);
}
... but I need to populate ListNotes in a Javascript after a user action.
Here is my javascript to make an ajax call to populate ListNotes:
function getReminders(e)
{
var userID = '#ViewBag.CurrUser';
$.ajax({
url: "/api/WoApi/GetReminders/" + userID,
dataType: "json",
type: "GET",
success: function (notes)
{
// Need to assign notes to Model.ListNotes here
}
});
}
Here's the method it calls with the ajax call. I've confirmed ListNotes does have the values I want; it is not empty.
public List<Koorsen.Models.Note> GetReminders(int id)
{
var notes = rep.GetNotesByCompanyID(id, 7, 7);
List<Koorsen.Models.Note> listNotes = new List<Koorsen.Models.Note>();
foreach (Koorsen.OpenAccess.Note note in notes)
{
Koorsen.Models.Note newNote = new Koorsen.Models.Note()
{
NoteID = note.NoteID,
CompanyID = note.CompanyID,
LocationID = note.LocationID,
NoteText = note.NoteText,
NoteType = note.NoteType,
InternalNote = note.InternalNote,
NoteDate = note.NoteDate,
Active = note.Active,
AddBy = note.AddBy,
AddDate = note.AddDate,
ModBy = note.ModBy,
ModDate = note.ModDate
};
listNotes.Add(newNote);
}
return listNotes;
}
If ListNotes was a string, I would have added a hidden field and populated it in Javascript. But that didn't work for ListNotes. I didn't get an error, but the text on the screen didn't change.
#Html.HiddenFor(x => x.ListNotes)
...
...
$("#ListNotes").val(notes);
I also tried
#Model.ListNotes = notes; // This threw an unterminated template literal error
document.getElementById('ListNotes').value = notes;
I've even tried refreshing the page after assigning the value:
window.location.reload();
and refreshing the panel bar the code is in
var panelBar = $("#IntroPanelBar").data("kendoPanelBar");
panelBar.reload();
Can someone explain how to get this to work?
I don't know if this will cloud the issue, but the reason I need to populate the model in javascript with an ajax call is because Model.ListNotes is being used in a Kendo Panel Bar control and I don't want Model.ListNotes to have a value until the user expands the panel bar.
Here's the code for the panel bar:
#{
#(Html.Kendo().PanelBar().Name("IntroPanelBar")
.Items(items =>
{
items
.Add()
.Text("View Important Notes and Messages")
.Expanded(false)
.Content(
#<text>
#RenderReminders()
</text>
);
}
)
.Events(e => e
.Expand("getReminders")
)
)
}
Here's the helper than renders the contents:
#helper RenderReminders()
{
if (Model.ListNotes.Count <= 0)
{
#Html.Raw("No Current Messages");
}
else
{
foreach (Note note in Model.ListNotes)
{
#Html.Raw(note.NoteText)
<br />
}
}
}
The panel bar and the helpers work fine if I populate Model.ListNotes in the controller and pass Model to the view. I just can't get it to populate in the javascript after the user expands the panel bar.

Perhaps this will do it for you. I will provide a small working example I believe you can easily extend to meet your needs. I would recommend writing the html by hand instead of using the helper methods such as #html.raw since #html.raw is just a tool to generate html in the end anyways. You can write html manually accomplish what the helper methods do anyway and I think it will be easier for you in this situation. If you write the html correctly it should bind to the model correctly (which means it won't be empty on your post request model) So if you modify that html using javascript correctly, it will bind to your model correctly as well.
Take a look at some of these examples to get a better idea of what I am talking about:
http://www.hanselman.com/blog/ASPNETWireFormatForModelBindingToArraysListsCollectionsDictionaries.aspx
http://haacked.com/archive/2008/10/23/model-binding-to-a-list.aspx
http://blog.stevensanderson.com/2010/01/28/editing-a-variable-length-list-aspnet-mvc-2-style/
So to answer your question...
You could build a hidden container to hold your list values like this (make sure this container is inside the form):
<div id="ListValues" style="display:none">
</div>
Then put the results your ajax post into a javascript variable (not shown).
Then in javascript do something like this:
$('form').off('submit'); //i do this to prevent duplicate bindings depending on how this page may be rendered futuristically as a safety precaution.
$('form').on('submit', function (e) { //on submit, modify the form data to include the information you want inside of your ListNotes
var data = getAjaxResults(); //data represents your ajax results. You can acquire and format that how you'd like I will use the following as an example format for how you could save the results as JSON data: [{NoteID ="1",CompanyID ="2"}]
let listLength = data.length;
for (let i = 0; i < listLength; i++) {
$('#ListValues').append('<input type="text" name="ListNotes['+i+'].NoteID " value="' + data.NoteID +'" />')
$('#ListValues').append('<input type="text" name="ListNotes['+i+'].CompanyID " value="' + data.CompanyID +'" />')
//for your ajax results, do this for each field on the note object
}
})
That should do it! After you submit your form, it should automatically model bind to you ListNotes! You will be able to inpsect this in your debugger on your post controller action.

Pass complex objects using ajax MVC

I have a view with multiple sections. i would like to update sections individually using partial views and ajax.
I have this so far:
Controller:
[HttpPost]
public PartialViewResult userdetailssettings(UserDetails model)
{ .... }
View Html:
<div id="userDetailsPartial">
#Html.Partial("_user_details", Model.userdetails)
</div>
Partial Html:
<div class="form-group">
<div class="col-md-12">
#Html.TextBoxFor(x => x.Forename, new { #class = "form-control", placeholder = "Enter your forename" })
#Html.ValidationMessageFor(x => x.Forename)
</div>
</div>
<div class="form-group">
<div class="col-md-12">
#Html.TextBoxFor(x => x.Surname, new { #class = "form-control", placeholder = "Enter your surname" })
#Html.ValidationMessageFor(x => x.Surname)
</div>
</div>
Javascript on View:
var detailsUrl = "#Url.Action("userdetailssettings", "UserLogin")";
var detailsmodel = JSON.stringify(#Html.Raw(Json.Encode(#Model.userdetails)));
$(document).on('click touchstart', '#saveDetails', function () {
$.ajax({
type: "POST",
dataType: 'json',
data: detailsmodel,
url: detailsUrl,
contentType: "application/json"
}).done(function (res) {
$("#userDetailsPartial").html(res);
addresssearch();
});
});
The model is being passed to the controller by the ajax, however the values are not that of the inputs. They are the original values passed from the controller to open the view.
I have tried wrapping the partial in tags and also tried adding form tags inside the partial.
I have also tried putting this code:
var detailsUrl = "#Url.Action("userdetailssettings", "UserLogin")";
var detailsmodel = JSON.stringify(#Html.Raw(Json.Encode(#Model.userdetails)));
Inside the click function.
Nothing I do passes the updated values from the inputs.
I have thought of creating a new instance of the model from the inputs in the javascript i.e.
var detailsmodel = [ { Forename: $('#Forename').val(), Surname: $('#Surname').val() } ];
But if I am just creating json why can I not just convert the bound model to json.

why can I not just convert the bound model to json
This is because you are using MVC, not MVVM.
The "bound model" is one way from the controller to the view via the model; it's possible you're mixing the term "bound model" with "model" and "binding".
If you POST the form, you'll get the model in the Action (based on parameters of course), but if you pass via ajax, you'll need to get the current values from the form (as in your comment 'creating a new instance of the model from the inputs').
You can generate data to pass via AJAX in various ways, such as:
var data = $("form").serialize();
rather than adding every input manually.
var detailsmodel = JSON.stringify... is set when the view is generated and will not change automatically using MVC.

That's because the data you're passing is statically set at page load, based on #Html.Raw(Json.Encode(#Model.userdetails)).
You would need to use something like $form.serialize(), or otherwise create the post body from the actual fields on the page.

Refresh Telerik Combobox list from another combobox

we are implementing an MVC solution using Telerik controls and
we have some problems refreshing the list of a Telerik ComboBox. Pratically we need to refresh the list of available values of a ComboBox every time the value selected in another ComboBox is changed. Below is our scenario:
Main ComboBox has a list of string values and we added an event;
Detail ComboBox has a list of values that depends on what is chosed from Main ComboBox;
When the event on Main ComboBox is fired the javascript calls an action in Controller;
The controller refresh the content of List02 (the datasource binded in ComboBox02)
Actually it runs all correctly but the Detail ComboBox does not refresh. What is wrong or missed?
Many Thanks for help
Main ComboBox:
<%=Html.Kendo().DropDownListFor(ourModel => ourModel.ModelPK)
.HtmlAttributes(new { #class="textboxDetails" })
.Name("combo01")
.BindTo((IEnumerable<ModelObject>)ViewData["List01"])
.DataTextField("descriptionText")
.DataValueField("valueID")
.Value(ourModel.ModelPK.ToString())
.Events(e =>
{
e.Select("onSelect");
})
%>
Detail Combobox:
<%=Html.Kendo().DropDownListFor(ourModel => ourModel.secPK)
.HtmlAttributes(new { #class="textboxDetails" })
.Name("combo02")
.BindTo((IEnumerable<ModelObject>)ViewData["List02"])
.DataTextField("descriptionText")
.DataValueField("valueID")
.Value(ourModel.Model02PK.ToString())
%>
Javascript on aspx page:
function onSelect(e) {
var dataItem = this.dataItem(e.item);
var itemPK = dataItem.valueID;
$.ajax({
type: 'POST',
url: '/controller01/action01',
data: "{'sentPK':'" + sentPK + "'}",
contentType: 'application/json; charset=utf-8',
success: function (result) {
},
error: function (err, result) {
alert("Error" + err.responseText);
}
});
}
Controller action:
[AcceptVerbs(HttpVerbs.Post)]
public void action01(model01 editModel, int sentPK)
{
//View data loads correctly
}

I do not think updating second combobox with ViewData will work in scenario:
.BindTo((IEnumerable)ViewData["List01"])
For the very first time when the page is rendered the value stored in ViewData object is used to fill the combobox but then onSelect all you are doing is, making an AJAX call to server. Server updates the ViewData object but as the combo box is already loaded with initial data, it will not be refreshed with new data.
You will have to refresh the second combobox on selection change event for first combo box.
Option 1:
Add following lines in your onSelect() success:
var combobox = $("#combo02").data("kendoComboBox");
combobox.dataSource.data(result);
Option 2:
Bind datasource of second combobox with server:
#(Html.Kendo().ComboBox()
.Name("products")
.HtmlAttributes(new { style = "width:300px" })
.Placeholder("Select product...")
.DataTextField("ProductName")
.DataValueField("ProductID")
.Filter(FilterType.Contains)
.DataSource(source => {
source.Read(read =>
{
read.Action("GetCascadeProducts", "ComboBox")
.Data("filterProducts");
})
.ServerFiltering(true);
})
.Enable(false)
.AutoBind(false)
.CascadeFrom("categories")
)
For a working example, refer this link.