Develop Reference

Dynamic / Changing variable in AJAX get Request

I have a page on a project I'm developing that is attempting to make an ajax request with a specific value assigned by the button's (there are multiple) id tag. This works; the value is successfully passed and an ajax call is triggered on every click.
When I try to make the call again to the same page with a different button the variables are reassigned however the GET request that is sent remains unchanged.
How do I pass a NEW variable (in this case id) passed into the GET request?
function someAJAX(target) {
var trigger = [target.attr('id')];
console.log[trigger];
$.ajax({
// The URL for the request
url: "onyxiaMenus/menuBase.php",
// The data to send (will be converted to a query string)
data: {
//class: target.attr("class"),
tableCall: true,
sort: trigger,
sortOrder: 'DESC',
},
// Whether this is a POST or GET request
type: "GET",
// The type of data we expect back
//The available data types are text, html, xml, json, jsonp, and script.
dataType: "html",
// Code to run if the request succeeds;
// the response is passed to the function
success: function (data) {
console.log("AJAX success!");
$('#prop').replaceWith(data);
}
,
// Code to run if the request fails; the raw request and
// status codes are passed to the function
error: function (xhr, status, errorThrown) {
console.log("Sorry, there was a problem!");
console.log("Error: " + errorThrown);
console.log("Status: " + status);
console.dir(xhr);
}
,
// Code to run regardless of success or failure
complete: function (xhr, status) {
console.log("The request is complete!");
$('#view').prepend(xhr);
}
});
}
$(document).ready(function () {
$(".sort").on( "click", function (e) {
//e.stopPropagation();
//e.preventDefault();
target = $(this);
//console.log(target.attr("class"));
console.log(target.attr("id"));
/* ADD CHILDREN TO ELEMENT*/
if (target.hasClass('asc')) {
target.removeClass('asc')
} else {
target.addClass('asc')
}
/* MANAGE CLASS ADD/REMOVE FOR TARGET AND SIBLINGS */
if (target.hasClass('btn-primary')) {
} else {
target.addClass('btn-primary')
}
someAJAX(target);
target.siblings().removeClass('btn-primary');
})
});

Try to call your ajax like this someAJAX.bind(target)();
Then in function become
function someAJAX() {
$.ajax({
// The URL for the request
url: "onyxiaMenus/menuBase.php",
// The data to send (will be converted to a query string)
data: {
//class: this.attr("class"),
tableCall: true,
sort: this.attr('id'),
sortOrder: 'DESC',
},
// Whether this is a POST or GET request
type: "GET",
// The type of data we expect back
//The available data types are text, html, xml, json, jsonp, and script.
dataType: "html",
// Code to run if the request succeeds;
// the response is passed to the function
success: function (data) {
console.log("AJAX success!");
$('#prop').replaceWith(data);
}
,
// Code to run if the request fails; the raw request and
// status codes are passed to the function
error: function (xhr, status, errorThrown) {
console.log("Sorry, there was a problem!");
console.log("Error: " + errorThrown);
console.log("Status: " + status);
console.dir(xhr);
}
,
// Code to run regardless of success or failure
complete: function (xhr, status) {
console.log("The request is complete!");
$('#view').prepend(xhr);
}
});
}

trigger doesn't seem to be defined anywhere. That's the only data that would be changing between your requests as the other ones are statically coded.
You just need to make sure trigger is defined and changes between the two requests.

Thanks for the input on this problem. I got down to the bottom of my problem. My requests were being handled correctly but dumping the tables was creating syntax errors preventing the appending of new information to my page.
Thanks for the quick replies!
It wall works now.

Why is Jquery $.ajax firing all statusCode on function call even with successful call

I have a simple Jquery ajax function call that looks like this.
function getUsers(){
var jqxhr = $.ajax({
url: "../assets/js/data/users.json",
type: "GET",
cache: true,
dataType: "json",
statusCode: {
404: handleError404("Error at getUsers();"),
500: handleError500("Error at getUsers();")
},
success: function (data) {
$.each(data, function(index, element) {
console.log(element.name);
});
}
});
}
The error handle functions look like this.
function handleError500(customMsg){
alert("Oops, there was an error: 500");
console.log("ERROR: 500 | "+customMsg);
}
function handleError404(customMsg){
alert("Oops, there was an error: 404");
console.log("ERROR: 404 | "+customMsg);
}
For some odd reason, even on a successful call with no apprent error 500 or 404 the statusCode functions are firing.
Any ideas? Thank you.

This is a common Javascript gotcha, but you're actually firing off these functions!
() after the name will actually invoke that function at that moment.
404: handleError404() // <-- it calls it immidiately
What you need to do, is create an anonymous function, which will be called later when the error actually happens, which inside of it will invoke your functions.
statusCode: {
404: function () { // <-- anonymous function won't get called until it needs to
handleError404("Error at getUsers();")
},
500: function () {
handleError500("Error at getUsers();")
}
},
Side note: If you weren't passing in parameters to your function,
you could actually ommit the anonymous function function () { /*
function call */ } part, and just call your function!
statusCode: {
404: handleErrors, // since no parameters are passed, this could be done
500: handleErrors
}

Because in the definition of the property of the object you are actually calling the function instead of defining one to be called when the code actually happens.
One thing you can try is:
statusCode: {
404: function() { handleError404("Error at getUsers();") },
500: function() { handleError500("Error at getUsers();") }
},

How to capture the 500 error message using jquery?

How can i capture the 500 error message using jquery? I want to keep on checking for the 500 error message for sometime until it changes and time out after 50 sec.
I used the code below to try to capture and check the 500 error message but it doesnt seem to catch the 500 error message. I can see it in the firebug
$.ajax({
statusCode: {
500: function() {
alert(" 500 data still loading");
console.log('500 ');
}
}
});

Dispite the accepted answer mentioned by #Danny, you can also do this in newer versions of jQuery.
var xhr = $.ajax({
url: "somewhere"
});
xhr.fail(function(xhr, textStatus, error) {
// Error handling stuff here ...
});
See Deferred Object.

Are you missing url in $.ajax like the one below
$.ajax({
url: "/path to page",
statusCode: {
500: function() {
alert(" 500 data still loading");
console.log('500 ');
}
}
});

You can check the status in error of ajax post please check the below code.
$.ajax({
.....
success: function (data) {
},
complete: function (XMLHttpRequest, textStatus) {
},
error: function (e, status) {
if (e.status == 404)
alert("404 error");
}
});
Thanks

Trapping Function not defined error in Javascript and jQuery

Okay, I do use firebug to determine when a function is not defined in Dev. What I would like to do in production is show a modal window saying an error has been received which would then redirect them to another page upon click. Not so easy.
Please understand that this function does work and the component that is called works. I am going to misspell the function call on purpose to demonstrate the error I am not receiving thru the jquery ajax function.
I am using .ajaxSetup to set up the default options for several ajax functions that will be running asynch:
$.ajaxSetup({
type: "POST",
dataType: "json",
url: "DMF.cfc",
data: {
qID: 1,
returnFormat: "json"
},
beforeSend: function() {
$('#loadingmessage').fadeIn(); // show the loading message.
},
complete: function() {
$('#loadingmessage').fadeOut(); // show the loading message.
}
}); //end AjaxSetup
The actual ajax call is:
$.ajax({
data: {
method: 'getCurrentIssues'
},
success: function(response) {
nsNewDebtshowDebtIssues(response);
},//end success function
error: function(jqXHR, exception) {
alert("Error running nsNewDebt.showDebtIssues");
}
}) //end getCurrentIssues Ajax Call
The error I forced is that the method run in the success function should actually be nsNewDebt.showDebtIssues. Firebug correctly displays in console the error nsNewDebtshowDebtIssues is not defined but the actual error message for the ajax call does not run, so if an enduser was running the page it would appear the page was hung.
So, In summary I want to know how to track when such an error occurs, preferrable to place in the error section of the .ajaxSsetup but if neccessary in each .ajax call.

It is not an ajax error, so you cannot handle it from the ajaxError method.
You should do a try/catch in the success method.
success: function(response) {
try {
nsNewDebtshowDebtIssues(response);
} catch (ex) {
//exception occured
//alert("Error running nsNewDebt.showDebtIssues");
alert( ex.message + '\n\tin file : ' + ex.fileName + '\n\t at line : ' + ex.lineNumber);
}
}

Before making the call, you can do:
if(typeof nsNewDebtshowDebtIssues == 'function') {
// .. call it ..
}

Well, the error actually occurs after the AJAX call has succeeded (since it comes from your success handler), so the error handler indeed won't be called.
If you want to use the same handler for actual AJAX request errors and for further errors originating from your success handler, you can define a named function and use it both as your error handler and from a try/catch block in your success handler:
function handleError(jqXHR, status, exception)
{
alert("Error running request.");
// Or print something from 'jqXHR', 'status' and 'exception'...
}
$.ajax({
data: {
method: "getCurrentIssues"
},
success: function(response, status, jqXHR) {
try {
nsNewDebtshowDebtIssues(response);
} catch (x) {
handleError(jqXHR, status, x);
}
},
error: handleError
});

ASP.NET MVC HttpException message not shown on client

I'm building a RESTful web api with asp.net mvc, which returns pure json data. On my client, I'm using backbone.js to communicate to it.
My question is, how do I capture the message in javascript? For eg. What if a user has no permission to delete or there was no item matching the id? I've been told to throw http errors instead of custom json.
So my code would be:
[HttpDelete]
public ActionResult Index(int id)
{
if (id == 1)
{
throw new HttpException(404, "No user with that ID");
}
else if (id == 2)
{
throw new HttpException(401, "You have no authorization to delete this user");
}
return Json(true);
}
How do I access the message in my javascript callback? The callback would look like:
function (model, response) {
alert("failed");
//response.responseText would contain the html you would see for asp.net
}
I do not see message i threw in the exception anywhere at all in the data that was returned from the server.

You should use the error callback on the client. The success callback is triggered only when the request succeeds:
$.ajax({
url: '/home/index',
type: 'DELETE',
data: { id: 1 },
success: function (result) {
alert('success'); // result will always be true here
},
error: function (jqXHR, textStatus, errorThrown) {
var statusCode = jqXHR.status; // will equal to 404
alert(statusCode);
}
});
Now there is a caveat with 401 status code. When you throw 401 HTTP exception from the server, the forms authentication module intercepts it and automatically renders the LogIn page and replaces the 401 status code with 200. So the error handler will not be executed for this particular status code.

I just answered this in my question What is the point of HttpException in ASP.NET MVC, but you can actually get that string if you use the HttpStatusCodeResult like this:
In your controller:
return new HttpStatusCodeResult(500,"Something bad happened")
And you can access "Something bad happened" using, say, jQuery $.ajax() like this:
$.ajax: {
url: "#Url.Action("RequestsAdminAjax", "Admin")",
type: "POST",
data: function(data) { return JSON.stringify(data); },
contentType: "application/json; charset=utf-8",
error: function (xhr, textStatus,errorThrown) {
debugger;
toggleAlert('<strong>Error: </strong>Unable to load data.', 'alert alert-danger');
}
},
and errorThrown will contain "Something bad happened".
HTH.