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Error in ajax request

I try to send ajax request in my SpringMVC project.
$.ajax({
contentType : 'application/json; charset=utf-8',
type : 'get',
url : 'order/get/'+i,
dataType : 'json',
data : {},
success : function(result) {
alert("Successfully!");
},
error : function(result, status, er) {
alert("error: "+result+" status: "+status+" er:"+er);
}
});
#RequestMapping(value = "/order/get/{id}", method = RequestMethod.GET)
public ResponseEntity<Order> getOrder(
#PathVariable("id") long id) {
Order order = orderService.getOrderById(id);
if (order == null) {
new ResponseEntity<Order>(HttpStatus.NOT_FOUND);
}
return new ResponseEntity<Order>(order, HttpStatus.OK);
}
But I always get error.
In controller method return object of 'order', but ajax throws 'GET net::ERR_CONNECTION_RESET'.
Why ?

The problem was that the Order entity serialized to JSON with all the attributes, including those that marked as #ManyToOne. This serialization Json was excessive, and the response was very huge. The entity class Order, had to designate attributes such annotation #JsonIgnore. After this error is gone and the answer is processed normally.

Call c# function with javascript code

I would like to call a code behind function from the client side.
The function cannot be static - should modified unstatic variabels.
I was able to create a non-visible button, and when I need that function I demonstrate a click on that btn.
How can I send parameters to that code behind function?

$.ajax({
url: '/ControllerName/ActionName',
type: "GET",
data: { param1: val1 },
success: function (res) {
alert(res) // res is results that came from function
}
});
This is the client side to call backend method. The server side to accept this request:
public ActionResult ActionName(string param1)
{
return View(param1);
}
In this case, we used jQuery, the javascript plugin, and we used AJAX request, also sending parameters.

Using MVC and jQuery
Client Side ( Using Razor )
$.ajax({
url: '#Url.Action("ActionName","ControllerName",new{parameters})',
type: "GET",
contentType: "application/json",
data: { param1: val1 },
success: function (res) {
alert(res) // res is results that came from function
},
error: function (jqXHR, error, errorThrown) {
console.log('An error as occured');
},
});
Server Side
[HttpGet]
public JsonResult ActionName(string param1)
{
return Json(param1, JsonRequestBehavior.AllowGet);
}
Note: HttpGet Verb is the default verb for every ActionResult/JsonResult

the button have a CommandArgument attribute that you can use to send a value to that function and you can read it as follow :
public void yourFunction(object sender,Eventargs e)
{
string args = ((LinkButton)sender).CommandArgument.ToString();
// rest of code here
}

Why ModelBinding don't work with FormData but works with RequestPayload?

I have been working with Web API and found an interesting observation that I am not able to understand.
controller:
public class UserController: ApiController
{
public void Post(MyViewModel data)
{
//data is null here if pass in FormData but available if its sent through Request Payload
}
}
viewModel
public class MyViewModel{
public long SenderId { get; set; }
public string MessageText { get; set; }
public long[] Receivers { get; set; }
}
JS that is not working
var usr = {};
usr.SenderId = "10";
usr.MessageText = "test message";
usr.Receivers = new Array();
usr.Receivers.push("4");
usr.Receivers.push("5");
usr.Receivers.push("6");
$.ajax(
{
url: '/api/User',
type: 'POST',
data: JSON.stringify(usr),
success: function(response) { debugger; },
error: function(error) {debugger;}
});
JS that is working
var usr = {};
usr.SenderId = "10";
usr.MessageText = "test message";
usr.Receivers = new Array();
usr.Receivers.push("4");
usr.Receivers.push("5");
usr.Receivers.push("6");
$.post( "/api/User", usr)
.done(function( data ) {
debugger;
});
So, if I pass on $.ajax with lots of other configuration like type, contentType, accept etc, it still don't bind model correctly but in case of $.post it works.
Can anybody explain WHY?

Try looking at what gets POSTed when you try it with $.ajax (e.g. with Fiddler of F12 tools of your choice). It can very well be that jQuery passes the data as URL-encoded string rather that as JSON literal.
To fix the issue try specifying dataType together with contentType parameter. Also, I don't think you need JSON.stringify, just pass the JSON literal you're creating:
$.ajax({
data: usr,
dataType: 'json',
contentType: 'application/json',
/* The rest of your configuration. */
});
Here's the TypeScript method that we use in one of our projects (ko.toJSON returns a string representing a JSON literal passed as a method parameter):
public static callApi(url: string, type?: string, data?: any): RSVP.Promise {
return new RSVP.Promise((resolve, reject) => {
$.ajax('/api/' + url, {
type: type || 'get',
data: data != null ? ko.toJSON(data) : null,
dataType: 'json',
contentType: 'application/json; charset=utf-8',
success: () => {
resolve.apply(this, arguments);
},
error: () => {
reject.apply(this, arguments);
}
});
});
}
Hope this helps.

JSON pass null value to MVC 4 controller in IE9

I got some problem while posting JSON data into MVC 4 controller.
Below method is working fine in Firefox but unfortunately failed in IE 9
The JavaScript :
var newCustomer = {
CustName: $("#CustName").val(),
CustLocalName: $("#CustLocalName").val(),
CustNumber: $("#CustNumber").val(),
CountryID: $("#SelectCountry").val(),
City: $("#City").val()
};
$.ajax({
url: '#Url.Content("~/CustomerHeader/CreateCustomerHeader")',
cache: false,
type: "POST",
dataType: "json",
contentType: 'application/json; charset=utf-8',
data: JSON.stringify(newCustomer),
success: function (mydata) {
$("#message").html("Success");
},
error: function () {
$("#message").html("Save failed");
}
});
and this is my controller :
public JsonResult CreateCustomerHeader(CustomerHeader record)
{
try
{
if (!ModelState.IsValid)
{
return Json(new { Result = "ERROR", Message = "Form is not valid! Please correct it and try again." });
}
RepositoryHeader.Update(record);
return Json(new { Result = "OK", Record = record});
}
catch (Exception ex)
{
return Json(new { Result = "ERROR", Message = ex.Message });
}
}
the "data" variable as in public JsonResult CreateCustomerHeader(CustomerHeader **data**) is getting NULL but while using FireFox it holds the correct value.
UPDATE : New method trying using $.post
function CreateNewCustomer(newCustomer) {
$.post("/CustomerHeader/CreateCustomerHeader",
newCustomer,
function (response, status, jqxhr) {
console.log(response.toString())
});
}

Based off the bit that you've shown, this is a simplified variation that may work more consistently, using jQuery.post() (http://api.jquery.com/jQuery.post/):
var data = {
CustName: $("#CustName").val(),
CustLocalName: $("#CustLocalName").val(),
CustNumber: $("#CustNumber").val(),
CountryID: $("#SelectCountry").val(),
City: $("#City").val()
};
$.post({
'#Url.Action("CreateCustomerHeader", "CustomerHeader")',
data,
function(response, status, jqxhr){
// do something with the response data
}).success(function () {
$("#message").html("Success");
}).error(function () {
$("#message").html("Save failed");
});
$.post() uses $.ajax as it's base, but abstracts some of the details away. For instance, $.post calls are not cached, so you don't need to set the cache state (and setting it is ignored if you do). Using a simple JavaScript object lets jQuery decide how to serialize the POST variables; when using this format, I rarely have issues with the model binder not being able to properly bind to my .NET classes.
response is whatever you send back from the controller; in your case, a JSON object. status is a simple text value like success or error, and jqxhr is a jQuery XMLHttpRequest object, which you could use to get some more information about the request, but I rarely find a need for it.

first of all I would like to apologize #Tieson.T for not providing details on JavaScript section of the view. The problem is actually caused by $('#addCustomerHeaderModal').modal('hide') that occurred just after ajax call.
The full script :
try{ ..
var newCustomer =
{
CustName: $("#CustName").val(),
CustLocalName: $("#CustLocalName").val(),
CustNumber: $("#CustNumber").val(),
CountryID: $("#SelectCountry").val(),
City: $("#City").val()
};
$.ajax({
url: '/CustomerHeader/CreateCustomerHeader',
cache: false,
type: "POST",
dataType: "json",
data: JSON.stringify(newCustomer),
contentType: "application/json; charset=utf-8",
success: function (mydata) {
$("#message").html("Success");
},
error: function () {
$("#message").html("Save failed");
}
});
}
catch(Error) {
console.log(Error.toString());
}
//$('#addCustomerHeaderModal').modal('hide')//THIS is the part that causing controller cannot retrieve the data but happened only with IE!
I have commented $('#addCustomerHeaderModal').modal('hide') and now the value received by controller is no more NULL with IE. Don't know why modal-hide event behave like this with IE9.
Thanks for all the efforts in solving my problem guys :-)

jQuery.ajax() parsererror

when i try to get JSON from http://api-v3.deezer.com/1.0/search/album/?q=beethoven&index=2&nb_items=2&output=json with:
(jQuery 1.6.2)
$.ajax({
type: "GET",
url: url,
dataType: "jsonp",
success: function (result) {
alert("SUCCESS!!!");
},
error: function (xhr, ajaxOptions, thrownError) {
alert(xhr.statusText);
alert(xhr.responseText);
alert(xhr.status);
alert(thrownError);
}
});
I get: parsererror; 200; undefined; jquery162******************** was not called
but with the JSON from http://search.twitter.com/search.json?q=beethoven&callback=?&count=5 works fine.
Both are valid JSON formats. So what is this error about?
[UPDATE]
#3ngima, i have implemented this in asp.net, it works fine:
$.ajax({
type: "POST",
url: "WebService.asmx/GetTestData",
data: "{}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (result) {
alert(result.d);
}
});
WebService.asmx:
[WebMethod]
public string GetTestData()
{
try
{
var req = System.Net.HttpWebRequest.Create("http://api-v3.deezer.com/1.0/search/album/?q=beethoven&index=2&nb_items=2&output=json");
using (var resp = req.GetResponse())
using (var stream = resp.GetResponseStream())
using (var reader = new System.IO.StreamReader(stream))
return reader.ReadToEnd();
}
catch (Exception) { return null; }
}

It's because you're telling jQuery that you're expecting JSON-P, not JSON, back. But the return is JSON. JSON-P is horribly mis-named, named in a way that causes no end of confusion. It's a convention for conveying data to a function via a script tag. In contrast, JSON is a data format.
Example of JSON:
{"foo": "bar"}
Example of JSON-P:
yourCallback({"foo": "bar"});
JSON-P works because JSON is a subset of JavaScript literal notation. JSON-P is nothing more than a promise that if you tell the service you're calling what function name to call back (usually by putting a callback parameter in the request), the response will be in the form of functionname(data), where data will be "JSON" (or more usually, a JavaScript literal, which may not be the quite the same thing). You're meant to use a JSON-P URL in a script tag's src (which jQuery does for you), to get around the Same Origin Policy which prevents ajax requests from requesting data from origins other than the document they originate in (unless the server supports CORS and your browser does as well).

in case the server does not support the cross domain request you can:
create a server side proxy
do ajax request to your proxy which in turn will get json from the service, and
return the response and then you can manipulate it ...
in php you can do it like this
proxy.php contains the following code
<?php
if(isset($_POST['geturl']) and !empty($_POST['geturl'])) {
$data = file_get_contents($_POST['geturl']);
print $data;
}
?>
and you do the ajax request to you proxy like this
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript">
$(function(){
$("#btn").click(function(){
alert("abt to do ajax");
$.ajax({
url:'proxy.php',
type:"POST",
data:{geturl:'http://api-v3.deezer.com/1.0/search/album/?q=beethoven&index=2&nb_items=2&output=json'},
success:function(data){
alert("success");
alert(data);
}
});
});
});
</script>
tried and tested i get the json response back...

At last i have found the solution. First of all, the webmethods in a webservice or page doesn't work for me, it always returns xml, in local works fine but in a service provider like godaddy it doesn't.
My solution was to create an .ahsx, a handler in .net and wrap the content with the jquery callback function that pass the jsonp, and it works .
[System.Web.Script.Services.ScriptService]
public class HandlerExterno : IHttpHandler
{
string respuesta = string.Empty;
public void ProcessRequest ( HttpContext context )
{
string calls= context.Request.QueryString["callback"].ToString();
respuesta = ObtenerRespuesta();
context.Response.ContentType = "application/json; charset=utf-8";
context.Response.Write( calls +"("+ respuesta +")");
}
public bool IsReusable
{
get
{
return false;
}
}
[System.Web.Services.WebMethod]
private string ObtenerRespuesta ()
{
System.Web.Script.Serialization.JavaScriptSerializer j = new System.Web.Script.Serialization.JavaScriptSerializer();
Employee[] e = new Employee[2];
e[0] = new Employee();
e[0].Name = "Ajay Singh";
e[0].Company = "Birlasoft Ltd.";
e[0].Address = "LosAngeles California";
e[0].Phone = "1204675";
e[0].Country = "US";
e[1] = new Employee();
e[1].Name = "Ajay Singh";
e[1].Company = "Birlasoft Ltd.";
e[1].Address = "D-195 Sector Noida";
e[1].Phone = "1204675";
e[1].Country = "India";
respuesta = j.Serialize(e).ToString();
return respuesta;
}
}//class
public class Employee
{
public string Name
{
get;
set;
}
public string Company
{
get;
set;
}
public string Address
{
get;
set;
}
public string Phone
{
get;
set;
}
public string Country
{
get;
set;
}
}
And here is the call with jquery:
$(document).ready(function () {
$.ajax({
// url: "http://www.wookmark.com/api/json",
url: 'http://www.gjgsoftware.com/handlerexterno.ashx',
dataType: "jsonp",
success: function (data) {
alert(data[0].Name);
},
error: function (data, status, errorThrown) {
$('p').html(status + ">> " + errorThrown);
}
});
});
and works perfectly
Gabriel