asp.net ashx handler: can't receive response - javascript

Hello everyone and thanks for your time.
Here is my javascript:
$('.sender').click(function (e) {
$.ajax({
type: "POST",
url: "fHandler.ashx",
data: { firstName: 'stack', lastName: 'overflow' },
// DO NOT SET CONTENT TYPE to json
// contentType: "application/json; charset=utf-8",
// DataType needs to stay, otherwise the response object
// will be treated as a single string
dataType: "json",
success: function (response) {
alert('success');
},
error: function (response) {
alert('error: ' + response);
console.log('err: '+response);
}
});
});
And here is the code in my .ashx handler:
public void ProcessRequest(HttpContext context)
{
context.Response.AppendHeader("Access-Control-Allow-Origin", "*");//to fix the allow origin problem
context.Response.ContentType = "text/plain";
string json = new StreamReader(context.Request.InputStream).ReadToEnd();
context.Response.Write(json);
}
public bool IsReusable
{
get
{
return false;
}
}
While the click event is working, my Ajaxrequest doesn't seem to get any response as the alert at success doesn't popup. I've debugged using the browser's network console and it return the expected response but it doesn't seem to reach the success function in the JavaScript code. Any insights or suggestions are welcome. Thanks.

In case you are still interested in the answer, try this before doing the request
var data = { firstName: 'stack', lastName: 'overflow' };
var jsonData = JSON.stringify(data);
and change your AJAX request to
$.ajax({
type: "POST",
url: "fHandler.ashx",
data: jsonData,
dataType: 'json',
contentType: 'application/json; charset-utf-8'
})
.done(function (response) {
// do something nice
})
.fail(function (jqXHR, textStatus, errorThrown) {
console.log("request error");
console.log(textStatus);
console.log(errorThrown);
});
Explanation
You are trying to send the plain data object. You must transform it into a Json string using JSON.stringify(object).
Changing the dataType isn't really a solution but a workaround.
Additional Notes
Also, I think you should use .done() and .fail(). See here for further details.

Related

how to detect a server error into a jquery ajax call?

I use Jquery to parse an json from url: the code is like this:
function fetchdata() {
var statusUrl = '/api/desk/j/';
$.ajax({
url: statusUrl,
dataType: "json",
type: 'post',
success: function(response) {
alert('ok');
},
error: function(xhr, status, error) {
var err = JSON.parse(xhr.responseText);
alert(err.message);
}
});
}
everything works fine, but if the server is not reachable I'm not able to detect it: I tried to do something in error: function, but seems that the code in error is fired only if the json has an error
have you got some ideas?
thank you!
You need to test the statusText from the jQuery textStatus response object. You can take advantage of your browser's developer console to inspect this object. You can expand the properties and methods for your perusal, however you wanna use it. Just click on the returned message of the console.log() to see these properties and methods that you wan't to use for error detection.
function fetchdata() {
var statusUrl = '/api/desk/j/';
$.ajax({
url: statusUrl,
dataType: "json",
type: 'post',
success: function(response) {
alert('ok');
},
error: function(textStatus) {
console.log(textStatus);
console.log(textStatus.statusText, textStatus.status);
}
});
}
fetchdata();

Webservice method not found by JQuery Ajax-Request error 500

JS:
function showComments(couponId) {
var jsontxt = JSON.stringify({ couponId });
$.ajax({
type: "POST",
url: "<% =Page.ResolveUrl("~/Admin/UserCoupons.aspx/GetComments") %>",
data: jsontxt,
contentType: 'application/json; charset=utf-8',
dataType: 'json',
//async:true,
success: function (result) {
alert("We returned: " + result.d);
},
failure: function (response) {
alert(response.d);
}
});
}
C#:
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static string GetComments(string couponId)
{
//will return precomipled generated html for display in div
return "Success";
}
The C# code is in page's code behind .cs file
i have solved this all before using stack over flow
thanks to experts here.
but this time there is some thing else
i am getting my debug pointer in page_load method then in master page's page load method. but debug doesn't enters to the GetComments
and getting exception
Unknown web method GetComments.
Parameter name: methodName
Below is the stackTrace
at System.Web.Script.Services.WebServiceData.GetMethodData(String methodName)
at System.Web.Script.Services.RestHandler.CreateHandler(WebServiceData webServiceData, String methodName)
at System.Web.Script.Services.RestHandler.CreateHandler(HttpContext context)
at System.Web.Script.Services.RestHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated)
at System.Web.Script.Services.ScriptHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated)
at System.Web.HttpApplication.MaterializeHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
Your data in ajax should be JSON.stringify({ couponId:'123' }) //parameter name & value.
function showComments(couponId) {
var jsontxt = JSON.stringify({ couponId:'123' });
$.ajax({
type: "POST",
url: "<% =Page.ResolveUrl("~/Admin/UserCoupons.aspx/GetComments") %>",
data: jsontxt,
contentType: 'application/json; charset=utf-8',
dataType: 'json',
//async:true,
success: function (result) {
alert("We returned: " + result.d);
},
failure: function (response) {
alert(response.d);
}
});
}
after a long google and all others and applying every possible solutions. finally, i found a solution. and that's
edit the file at ~/App_start/RouteConfig.cs
replace
settings.AutoRedirectMode = RedirectMode.Permanent;
with
settings.AutoRedirectMode = RedirectMode.Off;
this solved my problem. any ways thanks to all who took interest and showed their generosity.

Jquery AJAX Post: 500 (Internal Server Error)?

I am trying post a string to web service but I am getting this error (Google Chrome Extension Project):
jquery-2.1.1.min.js:4 POST http://localhost:49242/Service.asmx/test
500 (Internal Server Error)
Here is my ajax code:
var data = {};
data.param1 = words[0];
$.ajax({
data: JSON.stringify({ 'data': data.param1 }),
dataType: 'application/json',
url: 'http://localhost:49242/Service.asmx/test',
type: 'POST',
contentType: 'application/json; charset=utf-8',
success: function (result) {
alert(result);
},
failure: function (errMsg) {
alert(errMsg);
}
});
My service:
[WebMethod]
[System.Web.Script.Services.ScriptMethod(ResponseFormat = System.Web.Script.Services.ResponseFormat.Json)]
public string test(string param1) {
return param1;
}
I am working on this problem about 3 days. Can you help me ?
By the way, I have a question. I am posting json variable to service with ajax(like you see), but service returning xml value. Is there a problem or [System.Web.Script.Services.ScriptMethod(ResponseFormat = System.Web.Script.Services.ResponseFormat.Json)] this code block solving problem?
Your error come from your data parameter. Stringify data object instead of { 'data': data.param1 } :
var data = {};
data.param1 = words[0];
$.ajax({
data: JSON.stringify(data),
dataType: 'application/json',
url: 'http://localhost:49242/Service.asmx/test',
type: 'POST',
contentType: 'application/json; charset=utf-8',
success: function (result) {
alert(result);
},
failure: function (errMsg) {
alert(errMsg);
}
});
Your stringifyed data will result in {"param1":"Words"}, then your service should be able to bind the param1 parameter.
I was facing this type of error on AJAX post response. I was spending too much time behind this issue and finally I caught it.
It throws a 500 internal error because the AJAX response has a lot of content from the server so it returns a timeout of execution.
So I just added the line below and it's working fine.
Page.Server.ScriptTimeout = 300;

Web service receiving null with jQuery post JSON

The web service on http://localhost:57501/api/addDatabase has the following code.
[System.Web.Mvc.HttpPost]
public ActionResult Post(addDatabase pNuevaConeccion)
{
pNuevaConeccion.insertarMetaData();
return null;
}
The Ajax function is on a javascript that creates the JSON from the give values on http://localhost:1161/CreateServer.
$(document).ready(function ()
{
$("#createServer").click(function (e) {
e.preventDefault(); //Prevent the normal submission action
var frm = $("#CreateServerID");
var dataa = JSON.stringify(frm.serializeJSON());
console.log(dataa);
$.ajax({
type: 'POST',
url: 'http://localhost:57501/api/addDatabase/',
contentType: 'application/json; charset=utf-8',
crossDomain: true,
//ContentLength: dataa.length,
data: dataa,
datatype: 'json',
error: function (response)
{
alert(response.responseText);
},
success: function (response)
{
alert(response);
if (response == "Database successfully connected") {
var pagina = "/CreateServer"
location.href = pagina
}
}
});
});
});
When I run this code an alert pops up saying "undefined" but if I delete the contentType the alert doesn't show up. The problem is that the variables that the function Post (from the web service) receives are NULL even though I know that the JSON named dataa is not NULL since I did a console.log.
I have seen various examples and pretty much all of them say that I should use a relative URL but the problem is that since there are 2 different domains and when I tried it, it couldn't find the URL since it's not in the same localhost.
Web service should return a JSON format instead of null. like below example.
public JsonResult Post()
{
string output = pNuevaConeccion.insertarMetaData();
return Json(output, JsonRequestBehavior.AllowGet);
}
try to use this code for calling the web method
$.ajax({
method: "POST",
contentType: "application/json; charset=utf-8",
data: dataa,
url: 'http://localhost:57501/api/addDatabase/',
success: function (data) {
console.log(data);
},
error: function (error) {
console.log(error);
}
});
its my old code.(ensure action parameter variable name and post variable name are same)
$('#ConnectionAddres_ZonesId').change(function () {
var optionSelected = $(this).find("option:selected");
var id = { id: optionSelected.val() };
$.ajax({
type: "POST",
url: '#Url.Action("GetParetArea", "Customers")',
contentType: "application/json;charset=utf-8",
data: JSON.stringify(id),
dataType: "json",
success: function (data) {
$('#ConnectionAddres_ParentAreaId').empty().append('<option value="">Select parent area</option>');
$.each(data, function (index, value) {
$('#ConnectionAddres_ParentAreaId').append($('<option />', {
value: value.Id,
text: value.Area
}));
});
},
});
});
public ActionResult GetParetArea(int id)
{
var parents="";
return Json(parents, JsonRequestBehavior.AllowGet);
}

jQuery: Calling a function from AJAX request

I'm trying to call a function when I get success from my ajax call, but it's not working. This is what I've tryed so far.
function dtMRPReasonCode(dt) {
var data = null;
jQuery.ajax({
type: "POST",
data: {},
url: "Index.aspx/getMRPReasonCodeReport",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function(msg) {
if (msg.d) {
console.log(dt);
console.log(msg.d);
buildTableBody(dt, msg.d);
}
},
error: function(xhr, ajaxOptions, thrownError) {
alert("Error: dtMRPReasonCode");
}
});
return false;
}
function buildTableBody(dt, obj) {
dt.fnClearTable();
data = [];
$(obj).each(function(index, value) {
element = [];
element.push(value.Metric);
element.push(value.Region);
element.push(value.Plant);
element.push(value.Customer);
element.push(value.IMAC);
element.push(value.NotFilled);
element.push(value.Filled);
element.push(value.Total);
data.push(element);
});
dt.fnAddData(data);
}
Thanks in advance!
Edit #1
I used console.log in order to show you what I got from dt and msg.d (Image)
Edit #2
If I paste the commands from buildTableBody function in the success: handler instead of calling buildTableBody function in the success: handler it actually works:
function dtMRPReasonCode(dt) {
var data = null;
jQuery.ajax({
type: "POST",
data: {},
url: "Index.aspx/getMRPReasonCodeReport",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function(msg) {
dt.fnClearTable();
data = [];
$(msg.d).each(function(index, value) {
element = [];
element.push(value.Metric);
element.push(value.Region);
element.push(value.Plant);
element.push(value.Customer);
element.push(value.IMAC);
element.push(value.NotFilled);
element.push(value.Filled);
element.push(value.Total);
data.push(element);
});
dt.fnAddData(data);
},
error: function(xhr, ajaxOptions, thrownError) {
alert("Error: dtMRPReasonCode");
}
});
return false;
}
But it makes no sense to me, since this actually should work in both ways.
Pretty sure you have a typo on your function call
buildTableBody(td, msg.d);
should be
buildTableBody(dt, msg.d);
Also what is the return type from Index.aspx/getMRPReasonCodeReport? If it is string, you've got to unescape the string before you can treat it as JSON.
Try removing contentType : "application/json utf-8" from your AJAX call. That is the type of the data sent to the server. It is likely that you want the default content type.
Unless your server-side resource was configured to accept json it likely accepts application/x-www-form-urlencoded
http://api.jquery.com/jQuery.ajax/

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