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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");

Data update without page reload jinja2

The data has to be refreshed without page reload. Originally data is appeared on html with jinja2.
#app.route('/personal_account', methods=['POST'])
def welcome():
login = request.form['login']
data = get_default_user_data(login)
# ... processing
return render_sidebar_template("personal_account.html", data=data)
According to these data graph is building with chartist.js.
personal_account.html
<div id="data">
<ul id="consumed_values">
{% set count = 0 %}
{% for i in data.consumed_values %}
<li>{{ data.consumed_values[count] }}</li>
{% set count = count + 1 %}
{% endfor %}
</ul>
</div>
<canvas width="800" height="600" id="canvas"></canvas>
<button id="button">Update</button>
I need to update data. I am using ajax.
The function "request" make a post request to the server to the function get_selected_values in Python.
This function gives new data. But new data doesn't display in jinja2 on page. The data is still old.
personal_account.js
window.onload = draw();
function draw() {
var consumed_values = document.querySelectorAll('ul#consumed_values li');
var values = new Array();
for (var i = 0; i < consumed_values.length; i++) {
console.log(consumed_values[i].innerHTML);
values[i] = consumed_values[i].innerHTML;
}
var numbers = new Array();
for(var i=0; i<consumed_values.length; i++)
{
numbers[i]=i+1;
console.log(numbers[i]);
}
var ctx = document.getElementById('canvas').getContext('2d');
var grapf = {
labels : numbers,
datasets : [
{
strokeColor : "#6181B4",
data : values
}
]
}
new Chart(ctx).Line(grapf);
}
document.getElementById('button').onclick=function () {
request();
}
function reques() {
var first = selected[0];
var second = selected[1];
first.month = first.month+1;
second.month = second.month+1;
$.ajax({
type: 'POST',
url: '/get_selected_values',
success: function(response) {
alert('Ok');
draw();
},
error: function() {
alert('Error');
}
});
}
Function get_selected_values()
#app.route('/get_selected_values', methods=['POST'])
def get_selected_values():
# ...
data = fetch_selected_date(start_date=start_date, end_date=end_date, login=current_user.get_id())
if data:
# return jsonify({'result': True, 'data': data}) # does not work this way
# return jsonify({'result': False, 'data': []})
return render_sidebar_template("personal_account.html", data=data, result=1)
How to succeed in data's update and graph's rebuild?
EDIT 1
I am using the first version of get_selected_values function.
The request function look like this:
...
success: function(response) {
alert('Успешно получен ответ:!'+ response.data);
document.getElementById('consumed_values').innerHTML = response.data;
draw();
},
...
Data is updating successfully, but graph looks the same. How to fix?

OK here's my outlook on this. You're on the right track and there is a way to update the element without the need to re-draw the page in this instance. What's happening is that you are returning data from your get_selected_values() method but not doing anything with it once it's returned to your AJAX request.
So firstly, I'm going to draw your attention to your AJAX request:
$.ajax({
type: 'POST',
url: '/get_selected_values',
success: function(response) {
alert('Ok');
draw();
},
error: function() {
alert('Error');
}
});
When you're getting a successful response from this, you're seeing your "OK" alert in the UI, right? However nothing updates in the UI despite you calling on the draw() method?
You won't want to return a render_template from your Flask function in this case. You were already on the right track with returning JSON from your function:
if data:
# return jsonify({'result': True, 'data': data}) # does not work this way
When you return your JSON data, it will be stored in the response variable in your success function. If you're unsure of exactly what's going into that response variable then output its contents with something like alert(JSON.stringify(response)) in the success function of your AJAX request. From here you will see your data returned to your method.
Now you need to decide how you want to use that data to update your <div id="data"> element in your UI. You can do this just using JavaScript with a series of document.getElementById('element_id').innerHTML statements or such-like so that your element is populated with all of the updated data from your response.
This will auto-update the data you wish to have displayed without the need to refresh the page.
Now that you've done that, invoke your draw() function again and it should now use the updated data.
I hope this helps set you down the right path with this one!
AFTER EDIT 1
When you're originally populating <div id="data"> you are using a loop to populate a series of <li> tags in the element with your data.
When you are updating this element with your new data, you are just using .innerHTML to re-populate the parent <ul> element.
Your draw() method is looking to the data stored in the <li> elements.
Are you absolutely certain that, after you perform your update, your <div id="data"> element is in exactly the same (ie. expected) format to work with your draw() method? In that it's still in the structure:
<div id="data">
<ul id="consumed_values">
<li>Your updated data here...</li>
<li>More updated data...</li>
</ul>
</div>
This is the element structure that your draw() method is expecting to find. It's pulling its data in from each individual <li> element in the list. So these are the elements which need to store your updated values.

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.

How to invoke my post method when I'm changing dropdown list in ASP.NET MVC

I'm very new to MVC and Javascript so please be patient with me, I'm working on small application and I came to part when I need to select something from dropdown list and based on that selection I need to redirect user to another View, I also need to determine somehow where I should redirect user, so that is reason why I tried to pass parameter also ( database ID to my post method) but unfortunatelly this is not working, in section below I will post my code:
Method which is sending data to my DropDownList :
public ActionResult ShowArticleGroup()
{
List<ArticleGroup> articlesGroups = GroupsController.GetAllGroups();
ViewBag.articlesGroups = articlesGroups;
return View(articlesGroups);
}
[HttpPost]
public ActionResult ShowArticleGroup(string id)
{
//Here I wanted to take ID of selected Group and because there will be allways 3 Groups I can do if else and Redirect by ID
if(id =="00000000-0000-0000-0000-000000000002")
{
return RedirectToAction("Create","Article");
}
return RedirectToAction("Create", "Article");
}
And my VIEW - there is only one control on the view : just one dropdown, and based on selection I should be redirected to another view, and I wanted here to take ID of selected group and by that I wanted to redirect user to appropiate view:
#model IEnumerable<Model.ArticleGroup>
#{
ViewBag.Title = "Add new article";
}
<h3 style="text-align:center">Choose article group</h3>
#using (Html.BeginForm())
{
#Html.AntiForgeryToken()
<div class="form-horizontal">
<hr />
#Html.ValidationSummary(true)
<div class="form-group" style="text-align:center">
#Html.DropDownList("Group", new SelectList(ViewBag.articlesGroups, "GroupID", "GroupTitle.Name"), null, new { onchange = "document.location.href = '/Articles/ShowArticleGroup/' + this.options[this.selectedIndex].value;" })
</div>
</div>
}

First of all, usage of location.href on DropDownList seems wrong here:
#Html.DropDownList("Group", new SelectList(ViewBag.articlesGroups, "GroupID", "GroupTitle.Name"), null,
new { onchange = "document.location.href = '/Articles/ShowArticleGroup/' + this.options[this.selectedIndex].value;" })
AFAIK, location.href used for redirect to another page using HTTP GET, hence it will try to call first ShowArticleGroup action method without parameter, and the URL parameter simply ignored since given URL parameter only exist in POST.
To submit the form with DropDownList, you need to handle change event triggering POST into controller action method:
jQuery
<script type="text/javascript">
$(document).ready(function() {
$("#Group").change(function() {
var groupId = $("#Group").val();
$.post('#Url.Action("ShowArticleGroup", "ControllerName")', { id: groupId }, function (response, status) {
// response handling (optional)
});
});
});
</script>
DropDownList
#Html.DropDownList("Group", new SelectList(ViewBag.articlesGroups, "GroupID", "GroupTitle.Name"), null)
I recommend you using strongly-typed DropDownListFor with binding to a viewmodel approach if you want to pass viewmodel contents during form submit.
NB: $.post is shorthand version of $.ajax which uses POST submit method as default.
Related issues:
Autopost back in mvc drop down list
MVC 4 postback on Dropdownlist change

How do I create a web link inside a javascript function and pass cell value as a parameter to servlet?

I am creating a table dynamically with JavaScript as you can see below. I want users to be able to click on the first column value and pass the value of the cell as a parameter to a J#EE servlet. Can you help me? Basically the first column should be links to a new page with a country details. How can I do that? Thank you.
Where do I put the link code?
function oneSecondFunction() {
$.get('DisplayCountries', function(responseJson) {
if (responseJson != null) {
$("#countrytable").find("tr:gt(0)").remove();
var table1 = $("#countrytable");
$.each(responseJson, function(key, value) {
var rowNew = $("<tr><td></td><td></td><td></td><td></td><td></td><td></td><td></td>" +
"<td></td><td></td></tr>");
rowNew.children().eq(0).text(value['id']);
rowNew.children().eq(1).text(value['country1']);
rowNew.children().eq(2).text(value['country2']);
rowNew.children().eq(3).text(value['country3']);
rowNew.children().eq(4).text(value['country4']);
rowNew.children().eq(5).text(value['country5']);
rowNew.children().eq(6).text(value['country6']);
rowNew.children().eq(7).text(value['country7']);
rowNew.children().eq(8).text(value['country8']);
rowNew.appendTo(table1);
});
}
});
and here is the link code. I have tried several options and it doesn't work.
id

First, assign a class to the first <td> something like <td class="linkHolder">.
Then, write a click handler to send ajax request to servlet:
$('#countrytable').on('click', '.linkHolder', function() {
var link = $(this).html();
$.post('/myservlet', {url: link}, function(response) {
//handle response here
});
return false;
});
You can access the link on the servlet side with the request parameter url