Develop Reference

executing mvc controller using either Jquery or Ajax call

I am trying to mimic an mvc ActionLink. I want the whole row to be clickable. when the actionlink is clicked, it calls the connected controller and executes the code within. I want my Jquery/ajax call to do the same.
I've tried multiple ways of doing this with no luck. I'm currently at a point where the row is clickable and the Jquery sees that, however the ajax call does not execute. Or, if it does, the controller does not execute correctly
Here is the Jquery code that catches the click.
$(document).ready(function () {
$('#policyTable').on('click', '.clickable-row', function (event) {
$(this).addClass('primary').siblings().removeClass('primary');
var Id = $(this).closest('tr').children('td:first').text();
var url = "/Home/ReviewPolicy";
var uc = $(this).closest('tr').children('td:first').text();
alert("Does the click work? " + Id);
$.ajax({
type: "POST",
url: "/Home/ReviewPolicy",
dataType: 'text',
data: { Id: Id }
});
})
})
Here is the controller it is calling:
[HttpPost]
public ActionResult ReviewPolicy(string Id)
{
//Declare policyVM for individual policy
PolicyRenewalListVM model;
int val = Convert.ToInt32(Id);
using (Db db = new Db())
{
//Get the row
PolicyRenewalListDTO dto = db.RenewalPolicies.Find(val);
//confirm policy exists
if (dto == null)
{
return Content("This policy cannot be found.");
}
//initialize the PolicyRenewalListVM
model = new PolicyRenewalListVM(dto);
}
//return view with model
return View(model);
}
When the actionlink itself is clicked (It's not here in the code as I didn't see it being necessary for this problem) it fires and everything works as it should, but the jquery call, sending the very same value (Id) does not.

How to pass jQuery variable value to c# mvc?

How to pass jQuery variable value to c# mvc ?
I need to fetch the value of the variable btn in mvc code behind.
$('button').click(function () {
var btn = $(this).attr('id');
alert(btn);
$.ajax({
type: 'GET',
url: '#Url.Action("ActionName", "ControllerName")',
data: { id: btn },
success: function (result) {
// do something
}
});
});
Based on the variable value (Submit Button (or) Preview Button), my model will have Required validation on certain fields.
In my controller , i am calling as
[HttpGet]
public ActionResult ActionName(string id)
{
var vm = id;
return View(vm);
}
Though , ActionResult in controller is not invoked.
Jquery : alert(btn); -- is calling. I can see the alert window showing with the id. However, I am not able to retrieve the id in the controller.

You need to use jQuery.ajax() (or its shortened form jQuery.get()/jQuery.post()) with GET/POST method and set up a controller action with an argument to pass button ID:
jQuery (inside $(document).ready())
$('button').click(function () {
var btn = $(this).attr('id');
var url = '#Url.Action("ActionName", "ControllerName")';
var data = { id: btn };
// if controller method marked as POST, you need to use '$.post()'
$.get(url, data, function (result) {
// do something
if (result.status == "success") {
window.location = '#Url.Action("AnotherAction", "AnotherController")';
}
});
});
Controller action
[HttpGet]
public ActionResult ActionName(string id)
{
// do something
return Json(new { status = "success", buttonID = id }, JsonRequestBehavior.AllowGet);
}
[HttpGet]
public ActionResult AnotherAction()
{
// do something
return View(model);
}
If you want to pass retrieved button ID from AJAX into other action method, you can utilize TempData or Session to do that.

It is a nice coincidence that you use the word "fetch" to describe what you want to do.
jQuery runs in the browser as a frontend framework. Meaning that it runs on the client`s computer. Your MVC-C#-Code lies on the server. Therefore, if you want to send data between those two computers, you need to use the http protocol.
1. Ajax and REST:
Using an ajax call using http methods (post or put) to push your variable value as JSON to the backend`s REST api (route).
For this option, you might want to have a look at the fetch function of javascript.
2. HTML Forms
Use a html form where you store the variable value inside one input element. A form submission will perform a http post (by default) request to the backend as well and use all input element values as post parameters.

There are many ways to accomplish what you are looking to do, but I'll stick to using your code sample.
So what you need to do is utilize the .ajax call in jquery to send data from your view to your controller. More on that here: http://api.jquery.com/jquery.ajax/
Using your code, you'd put the .ajax call within your logic flow of what to do based on which button is clicked.
$("button").click(function ()
{
var btn = this.id;
if (btn == "previewButton")
{
$.ajax({
url: "/MyApp/MyAction",
type: "POST",
data: { btnId: btn },
dataType: "json",
async: true,
cache: false
}).success(function(data){
// do something here to validate if your handling worked
}).error(function(){
// Do something here if it doesnt work
});
}
}
You'll see that there is a URL. In my example i've chose MyApp as my controller and MyAction as the method of the controller in which we are posting values to. The ajax call posts 1 parameter with a property of btnId. If you need to pass more data, the property name in the jquery call should correspond with an argument of the actions method signature within the controller.
So my controller looks like
public MyAppController : Controller
{
[HttpPost]
public JsonResult MyAction(string btnId)
{
Debug.WriteLine("btnId: {0}", btnId);
return Json(new{ ButtonId= btnId });
}
}
This would be one way to handle passing values from your view to your controller using .ajax calls with jquery.
My preferred way is to use the Html helpers of Ajax.BeginForm which could be another option for you.
https://www.aspsnippets.com/Articles/ASPNet-MVC-AjaxBeginForm-Tutorial-with-example.aspx

How to get selected index changed value in controller mvc c#

I am getting value in a dropdown list and I wanted to get the selected value in controller when user select any value from the dropdown list. My view is -
#using (Html.BeginForm("ApReport", "Sales", FormMethod.Post))
{
#Html.DropDownList("Ddl", null, "All", new { #class = "control-label"})
#Html.Hidden("rddl")
}
controller -
[HttpPost]
public ActionResult ApReport(ApReport Ddl)
{
string Ddlvalue = string.Empty;
if (Request.Form["rddl"] != null)
{
Ddlvalue = Request.Form["rddl"].ToString();
}
}
but I am not getting any value. Also, I donot want to use any submit button.
Thanks in advance

The use of Ajax allows you as the developer to update the main view without reloading the entire page, as well as send data to the server in the background.
This is how I would have accomplished this task.
Firstly, I would have created an action in my controller which returns a JsonResult. This will return a JSON object to your calling jquery code, that you can use to get values back into your views. Here is an example of the action method.
[HttpGet]
public JsonResult YourActionName(string selectedValue) //Assuming key in your dropdown is string
{
var result = DoYourCalculation(selectedValue);
return Json(new { myResult = result }, JsonRequestBehavior.AllowGet);
}
Now, you need to add your jquery code. I would recommend you place this in a seperate javascript file referenced by your view.
Here is the JQuery code, with the ajax call to the Action in your controller. The Ajax call to the server is initiated by the 'change' event of your DropDown, handled in JQuery, as can be seen below.
$(function () {
$(document)
.on('change', '#Ddl', function(){
var valueofDropDown = $(this).val();
var url = '/YourControllerName/YourActionName';
var dataToSend = { selectedValue: valueofDropDown }
$.ajax({
url: url,
data: dataToSend,
type: 'GET',
success: function (dataReceived) {
//update control on View
var receivedValue = dataReceived.myResult ;
$('YourControlIDToUpdate').val(receivedValue);
}
})
});
};

Strange Behaviour with Ajax

I am working on ASP.net MVC 2.0 Application. I am using Ajax form. In that I have a dropdown and a button.
After clicking on button, i wanted to reload the dropdown if the Ajax request is sucessful.
So, i am calling a jquery Ajax function inside the callback function of the Ajax form.
In that jquery Ajax function, I am writing code to get the new data and binding to drop down so that it will be reloaded with new data.
Here, Every thing is working fine for the first time. But, when i click the button for the next time, the Ajax jquery function is called but it is not hitting contoller action method.
Code:
Here, are my jquery functions:
<script type="text/javascript">
function GetData() {
$.getJSON("/Home/GetUsers", null, function (data) {
var selectList = $("#ddlUsers");
selectList.empty();
alert("Inside Get Json method of jquery Ajax");
var defaultoption = $('<option>').text("--Select--").val("");
selectList.append(defaultoption);
$.each(data, function (index, optionData) {
var option = $('<option>').text(optionData.Text).val(optionData.Value);
alert(option);
selectList.append(option);
});
});
}
function Callback() {
GetData();
alert("Sucessfully done");
}
function Failed() {
alert("Sorry, an error occured while processing your request");
}
Methods inside Contoller:
[HttpGet]
public JsonResult GetUsers() ----> Method that is called from GetData() Ajax call
{
var data = GetUsersList();
return Json(data, JsonRequestBehavior.AllowGet);
}
public SelectList GetUsersList()
{
Db Fectch
return data;
}
I am unable to understand why the above indicated method is not called for second time yet the GetData() is called.
Please help..

I think it's the cache, try adding this line before your controller method:
[OutputCache(NoStore = true, Duration = 0, VaryByParam = "*")]
You can also place this line at the top of the controller, if you want it to be applied to all methods.

Call a class in javascript in visual studio

I have a controller class that I get data from database and return it in a function, Now I want to call this function in a js and set the data in variables to show in a page:
My code looks like: exampleController.cs
namespace iSee.WebApiHse.Controllers
{
public class expController : StandardController
{
public expController(
first myService,
ISystemSettings systemSettings,
IService myExpService)
{
_myService = MyService;
_systemSettings = systemSettings;
_myExpService = myExpService;
}
// GET data
public ActionResult Myexample(int id)
{
var elementIds = _systemSettings.ExpIds;
var myElements = CacheService.AllVisibleElements
.Where(x => elementIds.Contains(x.Id)).ToList();
var container = _kpiContainerService.Find(id);
var result = _myService.MonthByContainer(myElements, container);
return AsJson(result);
}
}
}
This works and I get the data. Now I have myExp.js that I need to use these data in it. How can I do that?
Thanks

You need to execute $ajax(..) (jquery syntax) request to your controller to pass and get compute information from the server.
For this your controller method, that you're going to call, has to be exposed for HTTP access.
More details on :
How to call controller method from javascript

Do you want work with your controller in View by JavaScript? It isn't good idea. You should pass Model to View and work with it or ajax and recieve json-data

An example that uses jQuery-ajax to call your C# method:
// javascript
var id = 987;
$.ajax({
url : '/expController/Myexample/',
type : 'GET',
data { id : id },
dataType : 'json', // <-- tell jQuery to decode the JSON automatically
success : function(response){
console.log(response);
}
});
This would call your method, passing in the value of id, then it would decode the JSON into the response object.
For plain Javascript ajax (no jQuery) see MDN Ajax.

You need to make a request to the Action Myexample. Usually this is done via AJAX:
In your view you could have:
function makeAJaxCall(idToSend) {
$.ajax({
url: '#Url.Action("exp", "Myexample")',
data: { id : idToSend },
type: "POST",
success: function(data) {
$("#HTMLElement").val(data.YourData);
}
});
}
Your response will come back in the data variable if the AJAX call succeeds. I have provided an example to show you how to change the value of an HTML element with the ID HTMLElement.
To invoke the function you can do:
makeAjaxCall(100);

You may load the JSON data in a var and pass it to the function in expjs.js, as:
var data = data_from_ajax();
exp_js_function(data);
data_from_ajax() would receive JSON data from your controller and action method.
Please consider this as a starting point and not as a copy-paste solution