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ajax POST sending null

I originally wrote the call as a GET but found a limitation with the length of the URI. Ideally, the call will take an object and turns it into a JSON format string, then sends it to a controller which will encrypt that string. The controller will send back a true/false if it succeeded.
My problem with POST, once it reaches the controller, the data parameter set from the ajax is null.
Here is the ajax/js:
var encActionURL = '#Url.Action("Encrypt", "Home")';
$.ajax({
url: encActionURL,
type: "POST",
contentType: "application/json; charset=utf-8;",
dataType: "json",
async: true,
traditional: true,
data: { jsonDoc: JSON.stringify(jsonDataFile) },
success: /*OnSuccess*/ function (result) {
// DO STUFF;
}
});
Here is the controller:
[HttpPost]
public bool Encrypt(string jsonDoc)
{
return serverConnection.Encrypt();
}
Note that, when I simply change the type to 'GET', it works great but when the form gets too long, it throws a 414 status error.
Most of the fixes found that I seem to have is the 'application/json'. I've also set ajax to traditional.

After going through a rabbit-hole of security tokens and validating forms, it wasn't any of that... this might be a solution for anyone using ASP.NET Core 2.1 MVC (5?) or just in general. Could have been a syntax mistake, return type mistake, or a combination.
New Ajax
$.ajax({
url: encActionURL,
type: "POST",
data: { 'jsonDoc': JSON.stringify(jsonDataFile) }, // NOTICE the single quotes on jsonDoc
cache: false,
success: /*OnSuccess*/ function (result) {
// DO STUFF;
}
});
New Controller
[HttpPost]
public ActionResult EncryptJSON(string jsonDoc) // Switch to ActionResult, formerly JsonResult
{
return Json(serverConnection.Encrypt());
}

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']);

getting data from controller in error function of jquery ajax -- Asp.net MVC

I have a jquery ajax script like following
$.ajax({
type: "POST",
url: "Main/receive", // the method we are calling
contentType: "application/json; charset=utf-8",
data: JSON.stringify({ 'p':$("#txtname").val() }),
dataType: "json",
success: function (result) {
alert('Yay! It worked!');
// Or if you are returning something
},
error: function (result) {
alert('Oh no zzzz:('+result.responseText);
}
});
And I am calling to Controller action method. The data is sending to the controller's action method and I am also receiving data from the controller. But the data that I am receiving is inside the error function of jquery ajax.
I want it to be inside the success function.
Why my success function is not getting called.
Following is my controller's action method,
[HttpPost]
public string receive(string p)
{
ViewBag.name = p;
return p;
}

The reason for the error is that you have specified that the returned data type be json (in the line dataType: "json",) but you method returns text. You have 2 options.
Change the controller method to return json using return Json(p);
Change the ajax option to dataType: "text", or just omit it
However you can improve your script as noted below
$.ajax({
type: "POST",
url: '#Url.Action("receive", "Main")', // don't hardcode url's
data: { p: $("#txtname").val() }, // no need to stringify (delete the contentType: option)
dataType: "json",
success: function (result) {
alert('Yay! It worked!');
},
error: function (result) {
alert('Oh no zzzz:('+result.responseText);
}
});
or even simpler
$.post('#Url.Action("receive", "Main")', { p: $("#txtname").val() }, function(result) {
alert('Yay! It worked!');
}).fail(function(result) {
alert('Oh no zzzz:('+result.responseText);
});
Notes: You should always use #Url.Action() to generate the correct urls, and it is not necessary in this case to stringify the data (but you need to remove the contentType: line so it used the default application/x-www-form-urlencoded; charset=UTF-8)
In addition, this is not strictly a POST (your not changing data on the server - but I assume this is just for testing). And there is no point in the line ViewBag.name = p; - it does nothing in your context, and as soon as you return from the method, ViewBag is lost anyway.

try to change your controller code as follows
[HttpPost]
public ActionResult List(string p)
{
ViewBag.name = p;
return Json(ViewBag);
}

Your controller method should look like this:
[HttpPost]
public ActionResult receive(string p)
{
return Json(p);
}

Pass a collection to MVC controller via jquery

I'm using ASP.NET MVC3 with Jquery. I'm trying to pass my form elements back to the controller using something like this (Please note I removed success and error code for simplicity):
var formElements = $("#myForm").serialize();
$.ajax({
type: "POST",
url: ScriptResolveUrl("~/Report/SubmitChanges"),
data: {collection: formElements},
success:
error:
dataType: "json"
});
My question is what should the parameter in my controller method look like:
Here is my controller method:
public ActionResult SubmitChanges(WHAT GOES HERE?)
{
}
So what I'm really looking for is what should be the type of the parameter going into the controller method? I want to be able to retrieve the values of the form elements in the controller.

So here is what I did. I have about 20-30 elements on my form so I really didn't want to have to turn each one into a parameter or list them all out in the collection.
In the jquery, I did the following:
var formElements = $("#myForm").serialize();
$.ajax({
type: "POST",
url: ScriptResolveUrl("~/Report/SubmitChanges"),
data: { parms: formElements },
success:
error:
dataType: "json"
});
It then goes into my controller as a string:
public ActionResult SubmitChanges(string parms)
I then found a function to parse that string (seems to be working)
NameValueCollection qscoll = HttpUtility.ParseQueryString(parms);
This seems to work without listing out all of the form elements.

Assuming your form elements all correspond to your model (let's say it's MyModel), then it should simply be:
public ActionResult SubmitChanges(MyModel model)
{
}
MVC default model binding will do the rest :).
Make sure you change your data definition in the jQuery ajax method though, you've already serialized it. Just do:
data: formElements,
I'm assuming the following in your jQuery ajax method is a copy and paste error?
success:
error:
If it's not, then make sure you either remove it, or change them to:
success: function (result) {
//do something
},
error: function () {
//do something on error
}

The problem is that their is no model that corresponds to my form
elements.
Then you can have this:
public ActionResult SubmitChanges(int id, string name)
{
}
And then pass in the individual items:
var o = {
id = $("#id_elem_id").val(),
name = $("#name_elem_id").val()
}
$.ajax({
type: "POST",
url: ScriptResolveUrl("~/Report/SubmitChanges"),
data: JSON.stringify(o),
success:
error:
dataType: "json"
});
where id_elem_id and name_elem_id are the ids of your html elements. And add any additional parameters you need, just follow along.

You were almost there. Just get rid of the brackets around your data parameter:
var formElements = $('#myForm').serialize();
$.ajax({
type: 'POST',
url: ScriptResolveUrl("~/Report/SubmitChanges"),
data: formElements,
success: function(result) {
// handle the success of the AJAX request
},
error: function() {
// an error occurred
}
});

Calling a C# method with jquery

I am trying to call a method with jQuery on a button click.This is waht I have so far:
$("a.AddToCart").click(function () {
var link = document.URL;
$.ajax({
type:"POST",
url: "/Account/AddToCartHack",
data: {url : link},
contentType: "application/json; charset=utf-8",
dataType: "json"
});
});
[WebMethod]
public void AddToCartHack(string url)
{
GeneralHelperClass.URL = url;
}
What I am trying to do here is when I click the link with class add to cart I want to call the method AddToCartHack and pass it the curent URL as a parameter.
I must be doing something wrong because it seems that AddToCartHack is not being called.
What am I doing wrong?

There are quite a lot of issues with your code, I don't know where to start. So let's conduct an interactive refactoring session with you (if you don't care about my comments but just want to see the final and recommended solution, just scroll down at the end of answer).
First: you don't seem to be canceling the default action of the anchor by returning false from the .click() event handler. By not doing this you are actually leaving the browser perform the default action of the anchor (which as you know for an anchor is to redirect to the url that it's href attribute is pointing to. As a consequence to this your AJAX call never has the time to execute because the browser has already left the page and no more scripts are ever running). So return false from the handler to give your AJAX script the possibility to execute and stay on the same page:
$("a.AddToCart").click(function () {
var link = document.URL;
$.ajax({
type:"POST",
url: "/Account/AddToCartHack",
data: {url : link},
contentType: "application/json; charset=utf-8",
dataType: "json"
});
return false;
});
Second: You have specified contentType: 'application/json' request header but you are not sending any JSON at all. You are sending a application/x-www-form-urlencoded request which is the default for jQuery. So get rid of this meaningless parameter in your case:
$("a.AddToCart").click(function () {
var link = document.URL;
$.ajax({
type:"POST",
url: "/Account/AddToCartHack",
data: {url : link},
dataType: "json"
});
return false;
});
Third: You have specified that your server side code will return JSON (dataType: 'json') but your server side code doesn't return anything at all. It's a void method. In ASP.NET MVC what you call C# method has a name. It's called a controller action. And in ASP.NET MVC controller actions return ActionResults, not void. So fix your contoller action. Also get rid of the [WebMethod] attribute - that's no longer to be used in ASP.NET MVC
public class AccountController: Controller
{
public ActionResult AddToCartHack(string url)
{
GeneralHelperClass.URL = url;
return Json(new { success = true });
}
}
Fourth: you have hardcoded the url to the controller action in your javascript instead of using server side helpers to generate this url. The problem with this is that your code will break if you deploy your application in IIS in a virtual directory. And not only that - if you decide to modify the pattern of your routes in Global.asax you will have to modify all your scripts because the url will no longer be {controller}/{action}. The approach I would recommend you to solve this problem is to use unobtrusive AJAX. So you would simply generate the anchor using an HTML helper:
#Html.ActionLink(
"Add to cart",
"AddToCartHack",
"Account",
null,
new { #class = "AddToCart" }
)
and then unobtrusively AJAXify this anchor:
$('a.AddToCart').click(function () {
var link = document.URL;
$.ajax({
type: 'POST',
url: this.href,
data: { url : link }
});
return false;
});
Fifth: You seem to be employing some document.URL variable inside your .click() handler. It looks like some global javascript variable that must have been defined elsewhere. Unfortunately you haven't shown the part of the code where this variable is defined, nor why is it used, so I cannot really propose a better way to do this, but I really feel that there's something wrong with it. Or oh wait, is this supposed to be the current browser url??? Is so you should use the window.location.href property. Just like that:
$('a.AddToCart').click(function () {
$.ajax({
type: 'POST',
url: this.href,
data: { url : window.location.href }
});
return false;
});
or even better, make it part of the original anchor (Final and recommended solution):
#Html.ActionLink(
"Add to cart",
"AddToCartHack",
"Account",
new { url = Request.RawUrl },
new { #class = "AddToCart" }
)
and then simply:
$('a.AddToCart').click(function () {
$.ajax({
type: 'POST',
url: this.href
});
return false;
});
Now that's much better compared to what we had initially. Your application will now work even with javascript disabled on the page.

place script method this way as shown below
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]

Add Success and error function to check your ajax functionality
...
$.ajax({
type:"POST",
url: "/Account/AddToCartHack",
data: {url : link},
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function(){
alert('success');
},
error:function(){
alert('error');
}
});
....

If this is Asp.Net webforms you will need to make the webmethod static or the method cannot be accessed through JavaScript.

$(document).ready(function () {
$.ajax({
url: "Testajax.aspx/GetDate",
data: "f=GetDate",
cache: false,
success: function (content) {
$('#tableData').append('My Dear Friend');
alert(content);
},
failure: function (response) {
alert("no data found");
}
});
});