Advice Needed : MVC4 and Jquery Ajax - c#

Need some advice - doing a project with MVC 4 - used to Forms and Ajax.
Normally I do AJAX calls
My code looks like this :
$.ajax({
type: "POST",
contentType: "application/json; charset=utf-8",
url: "#SiteConfig.BaseUrl/assessment/getquestion",
data: "{'AssessmentId':" + "'" + AssessmentId + "'" + ",'PageNumber':" + PageIndex + "}",
dataType: "json",
beforeSend: function(){
$('#ajaxLoader').show();
$('#questionContainer').hide();
},
success: function (msg) {
var data = msg.d;
},
complete: function(){
$('#ajaxLoader').hide();
$('#questionContainer').show();
},
error:function (request, status, error){
alert(request.responseText);
alert(request);
$('#ajaxLoader').hide();
//window.location = '#SiteConfig.BaseUrl/questionnaire';
}
});
[HttpPost]
public JsonResult GetQuestion(Guid AssessmentId, Int32 PageNumber)
{
... my code
return this.Json(assessmentInfo, JsonRequestBehavior.AllowGet);
}
I keep getting HTML that is returned instead of JSON - it basically just sends me the HTML for the entire page back in the method - what am I doing wrong?
Debugging the problem yields the following result from javascript:
Javascript : SyntaxError: JSON.parse: enexpected character
Furthermore, if I add a breakpoint to the C# GetQuestion method, it is not being hit.
Could this be a URL routing issue?
Also, for the guys that are commenting on Naming conventions : the purpose of this method is to get a question. Naming conventions should follow business logic first, then technical conventions. Calling the method postquestion implies that I am posting a question which doesnt make sense at all.

You should edit your GetQuestion method like this:
[HttpPost]
public JsonResult GetQuestion(Guid AssessmentId, Int32 PageNumber)
{
//my code
return this.Json(myClass,JsonRequestBehavior.AllowGet);
}
Please also get your naming conventions right, if you get something, call the method GET. If you post someting call the method POST.

Ok, I found the problem.
It was indeed a routing problem that caused the issue.

Related

Asp .net core project: Ajax call can't reach controller (400 status code)

I'm refactoring my ASP .net core project and I want to make use of some Ajax calls, but I'm facing the following problem: when I try to send a request to a method in a controller of my project but it doesn't work.
I have a modal with the following button:
<button onclick="reviewRestaurant(#item.RestaurantId)" class="btn btn-outline-primary">Add review</button>
the reviewRestaurant() function looks like this:
function reviewRestaurant(restaurantId) {
let rating = $("input[type=radio]:checked").val();
let review = $('textarea').val();
let data = { restaurantId, rating, review };
$.ajax({
type: "POST",
url: `/Restaurants/Review`,
data: JSON.stringify(data),
success: function (res) {
// TODO: work on this later
},
error: function (err) {
console.log(err);
}
});
}
And the method that I wanna call in the Restaurants controller looks like so:
[Authorize]
[HttpPost]
public async Task<IActionResult> Review(int restaurantId, string rating, string content)
{
var username = this.User.Identity.Name;
await this.restaurantsService.Review(restaurantId, username, rating, content);
return this.RedirectToAction("Details", new { id=restaurantID });
// the output of this method will be refactored later once I manage to get to it
}
The problem is I cannot reach the Review method in the controller. I get the 400 status code and I don't know how to fix it. I tried using DTO and [FormData] attribute for the method parameters and tried passing the data without stringifying it still nothing works.
If anyone can help me I would be very grateful. I'm relatively new to ajax calls and simply cannot see where my mistake is.
You can try this solution:
Create a common class for your parameters (int restaurantId, string rating, string content) and use FromBody. => Review([FromBody] YourClassName)
And write this parameters in your ajax code.
contentType: 'application/json; charset=utf-8',
data: 'json'
I hope it will help you.
Here is a working demo which I test.
#section Scripts
{
<script>
function reviewRestaurant(restaurantId) {
let rating = $("input[type=radio]:checked").val();
let content = $('textarea').val();
let data = { restaurantId, rating, content };
$.ajax({
type: "POST",
url:'/Restaurants/Review',
data: data,
success: function (res) {
// TODO: work on this later
},
error: function (err) {
console.log(err);
}
});
}
</script>
}

How to get value from controller back to $.Ajax

My setup: asp.net mvc web app
I am having trouble getting a value from a controller back to the $.Ajax call (see below). The controller deletes a record in a database and counts some other records.
$.ajax({
type: "POST",
url: actions.action.RemoveItem + "?id=" + dataId,
contentType: "application/json; charset=utf-8",
dataType: "json",
traditional: true,
success: function (result) {
alert(result);
},
error: function (result) {
alert("Error");
}});
[HttpPost]
public JsonResult RemoveItem(int id)
{
... delete a record in the db
itemsCount = .... counts of some other records in the db
if (deletedRecord.id != null)
{
return Json(new { itemsCount });
}
else
{
return JsonError();
}
}
The ajax call and the controller work properly, however when I try to use the returned value in the success function, the alert(result) gives [object object].
I have looked through all related posts, but could not find a solution that worked. Could someone give me a hint where the problem could be and how to make it work?
Thank you in advance and regards, Manu
Result is a javascript object so alert works properly. If you want to alert it's structure as JSON use JSON.stringify() method like this:
alert(JSON.stringify(result));
If you want to access your itemsCount, just use dot or bracket notation:
alert(result.itemsCount);
alert(result['itemsCount']);

Ajax post not working MVC 5

I'm trying to post data into a controller but it doesn't seems to work, I need the post to include the content of the view into a div when done but I cant quite achieve it
Here's my js function:
function show(num) {
$.ajax({
dataType: "html",
type: "POST",
url: "Student/Schedule",
data: { number: num },
success: function (a) {
// Replace the div's content with the page method's return.
alert("success");
$('#schedule').load(a);
}
});
}
And, here's my controller:
public ActionResult Schedule(String number)
{
return View(number);
}
I am a noob in MVC and C#, so any help is welcome.
There are somethings that you should fix to solve the problem.
Change Url to "/Student/Schedule"
You are using "Student/Schedule" as url, so you are trying to call an action named "Student".
Add [HttpPost] to your action.
You should return PartialView("Schedule", number);.
When you use return View(number) it uses the string value of number as your view name. You should explicitly pass view name and model.
Use $('#schedule').html(a);
It's better to add an error function to your ajax call to be able to find errors:
error: function (jqXHR, textStatus, errorThrown) {
alert(errorThrown);
//or you can put jqXHR.responseText somewhere as complete response. Its html.
}
Your action should return a Partial View, not a View.
Change your action to:
[HttpPost]
// by the way use string instead of String
public ActionResult Schedule(string number)
{
return PartialView("_Schedule", number);
}
Then, you'll need to create a partial view named _Schedule.cshtml.
Also, you need to change $('#schedule').load(a); to $('#schedule').html(a); And, I'd suggest that you use a Url.Action to set your url in your ajax call, like this:
function show(num) {
$.ajax({
dataType: "html",
type: "POST",
url: '#Url.Action("Schedule", "Student")',
data: { number: num },
success: function (a) {
// Replace the div's content with the page method's return.
alert("success");
$('#schedule').html(a);
}
});
}
I had the same issue what i did was adding jquery.unobtrusive-ajax.js to my scripts

Ajax Webmethod not being called

I make a total of four Ajax calls in my .NET application. Three of them work without a hitch except the last one.
Note: I HAVE to use .aspx for these calls and not mypage.aspx/mymethod because of our architectural constraints.
Ajax call that works:
$.ajax({
type: "POST",
url: "myaddress/GenerateOpinionHTML.aspx",
data: JSON.stringify({ id: featureId, pageNumber: pageNumberIndex }),
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (msg) {
SOME PROCESSING (IT WORKS)
},
error: function (xhr, status, error) {
var err = xhr.responseText;
console.log(err);
}
});
and
[WebMethod]
public static string GenerateOpinionHTML(int id, int pageNumber)
{
// ...
}
Ajax call that does not work:
console.log("SUBMITOPINIONCLICK");
var param = " ";
$.ajax({
type: "POST",
url: "myaddress/SaveOpinion.aspx",
data: JSON.stringify({ parameter: param}),
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (msg) {
console.log("SAVE OPINION SUCCESSFUL");
console.log(msg.d);
CloseLB('GiveOpinionLB');
},
error: function (xhr, status, error) {
var err = xhr.responseText;
console.log("ERROR " + "STATUS: " + status);
}
});
and
[WebMethod]
public static string SaveOpinion(string parameter)
{
// ...
}
The web method SaveOpinion is never called according to the logs. Do you have any ideas or suggestions? I tried adding parameters, without parameters, checking my web.config file (though I shouldn't have since the other calls work)...
The error I get on the browser console is a "parseerror". I'm certain I wouldn't be getting an error if the method was called.
I think your URL should be like
url: "Your FolderName/PageName/Function Name",
Like
url: "myaddress/SaveOpinion.aspx/SaveOpinion"
but in your code this is different so that please check.
Have you checked if method SaveOption return something to the client?
If you specify dataType as json, you should return (at least): {}
Ok so we "solved" it. We just found a very dirty band-aid workaround that works.
We made a custom handler (.ashx) that we defined in our architecture as a SaveOpinion.aspx page.
We then called this custom handler page with jQuery and voilĂ  it works, we had to obviously pass all necessary parameters manually, ie. fetching all values from textBoxes etc with jQuery and not from the context as we did before.
Since this is run in some sort of thread (I don't really know the details) we had to configure it so that it simulates the same user authentification.
Anyway I hope this provides some measure of guidance for those with this kind of obscure problems.

ajax call to c# mvc sends both post and get

I've looked at several solutions for making an ajax call and by not this issue mentioned anywhere i feel it might be something specific to the environment i'm working with.
My controller:
[HttpPost]
public ActionResult ChangeDefualtCC(string a)
{
return Json("ok");
}
[HttpGet]
public ActionResult ChangeDefualtCC()
{
return Json("ok");
}
JS:
$("nevermind").change(function () {
$.ajax({
type: "POST",
url: "/Account/ChangeDefualtCC",
dataType: "json",
data: {
a: "A"
},
success: function (data) { console.log(data)},
error: function (data) { console.log("error");}
});
});
The Controller code is never hit, and this is what i'm seeing in chrome after the ajax call:
EDIT 2: The page hits the [HttpGet] method.
EDIT:
I tagged Ektron as well because it is used in the project, and it is possible that it is affecting the call.
My Routes:
Update: I have tried using Get, as well as Post, and also returning back to the View I was in, I get the 302 everytime.
any ideas?
It looks like it finds the "get" because you don't have a parameter in that call. I think you might be missing the content type from your ajax call, so the model binder cannot parse the content of your post as a parameter.
$.ajax({
type: "POST",
url: "/Account/ChangeDefualtCC",
contentType: 'application/json; charset=utf-8',
dataType: "json",
data: {
a: "A"
},
success: function (data) { console.log(data)},
error: function (data) { console.log("error");}
});
Your code seems to be absolutely correct.
This not be exact solution but try this may it work.
$("nevermind").change(function () {
$.post("/../Home/ChangeDefualtCC", { a: "A" }, function (data) {
console.log(data)
});
});
Our project is integrated with the CMS Ektron. We later discovered that Ektron is hit before the C# code, and has some affect to any url without a trailing url.
Thanks for all the help

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