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Sending $ajax via jQuery to C# codebehind not working

I am having unexplained behavior when I post from jquery using ajax to C#.
1) The main page is called not the method I am requesting in jQuery.
To work around this I simply put an if in the page load so that if a particular item is in the querystring it will trigger a series of commands. It does hit that if statement and runs the code perfectly fine. There are some methods that do things like change a color on the map. These never actually happen. I can set a label and it will pass right over it but the label remains unset.
2) strangely enough.... my page has a timer with a refresh on it. It refreshes the page and now the changes are processed.
Here is the way I am calling my method in jQUery:
function mycmethod(param)
{
//alert(precinct);
$.ajax({
url: "myPage.aspx/someMethod",
type: 'POST',
data: "params=" + param,
success: function iGotData(responseJSON) {
// alert("Worked");
},
error: function (xhr, status, errorThrown) {
console.log("Error: " + errorThrown);
console.log("Status: " + status);
console.log(xhr);
alert("Didnt work:" + errorThrown);
},
})
};
It was originally set to async: true but that didn't make a difference.
The method its not calling on load is:
[WebMethod][ScriptMethod]
public Boolean someMethod(string param)
{
setFeatures();
GenerateMap();
return true;
}
I doubt its relevant but I am calling a jquery call with over mouse over of a specific element. That jquery calls a function which calls a asmx web service that returns some jSON. I am calling the mycmethod after the JSON is returned.
Why is my UI elements not responding until the page refreshes. If not, is there a way I can force a refresh like the timer does?

[WebMethods] methods should be declared as static.
I've also found that you might need to specify the content type in your ajax call:
contentType: "application/json; charset=utf-8"
Also, your data option looks suspicious. Maybe you should append it to the url option:
url: "myPage.aspx/someMethod?params" + parm
or, more ideally, send it as either a JSON object or a JSON string:
data: {
params: param
}
or
data: JSON.stringify({
params: param
})

If I understand you correctly, you're loading the page, then calling the server via ajax and expecting the server to change UI elements of the currently loaded page.
It doesn't work like that, unfortunately. Once you've served the page, the server itself cannot manipulate that page without doing a refresh/post back (or something along those lines).
If you want to update the UI without doing a refresh/post back you can have your WebMethod return HTML, and your jQuery success method can update the relevant controls.
Alternatively you could use jQuery's .get() to retrieve a fresh copy of the page via ajax, and update your current page like that. (although it's less efficient)

Update the Page without refresh it

Goal:
When you click on the row (1), new data shall display (3.) without the whole webpage will be updated/refreshed.
Problem:
1.
I need advice and I don't know where to find the funciton to display the picture number 2 and how to display the data and new object (3.) without update/refresh the whole webpage?
And
2
How do you create an icon to display loading picture?
Information:
- The page is based on ASP.mvc with C#

Use ajax functionality of either jquery or MVC ajax helpers.
You can find jquery ajax here.
and MVC ajax helper lib here
and here
you can make an ajax call to the server's websevice and it can return one of the well known web format (for e.g. json or XML). When the webservice call returns you can then "inject" the data in your html page with either javascript (dom manipulation) or using MVC helpers.
Here's one that could help..
http://www.asp.net/mvc/tutorials/older-versions/javascript/creating-a-mvc-3-application-with-razor-and-unobtrusive-javascript

You Can use jquery ajax which would call async action method(function). Data is returned the form of Json. You can write code to deserilize data and display it using jquery.
Create a Action method which would return JsonResult as viewresult as
public JsonResult GetJsonData()
{
return Json(new
{ testDataResult =TestDataResultObj.Data
JsonRequestBehavior
}, JsonRequestBehavior.AllowGet);
}
and write following jquery code:-
if (GetDataAsyc()) {
$.ajax({
type: "GET",
data: { testData: testDataResult },
url: url,// url of action method to be called asynch
dataType: "json",
cache: false,
traditional: true,
contentType: "application/json",
success: function (data) {
// on success assign testDataResult to messages //line
$("#MessagesLines").html(testDataResult .Html);
}
},
error: function () {
//Display error message
$("ErrorMsg").html("There was error whey trying to process your request")
}
});
}

Use ajax+PartialViews to update some page sections

FireFox and IE9 tries to download or show json-response instead of letting javascript parse it

Update
My problem was that I used event.preventDefault() instead of return false to hinder the form from posting normally. FF and IE didn't like that and broke the JS by that line. I removed that and appended return false at the end and this solved the problem. Thanks to Darin Dimitrov for the extensive checklist.
Original question
I'm using ASP.NET MVC3 and jquery ajax to post json-data to the server and receive a response. However, when I'm using Chrome it reads the json-response normally, updating the divs that I want etc. With IE and FF it doesn't work though. They read just the response and shows only that on the page.
I saw some other threads mentioning to define the mime type as "text/plain". This changed the previous behavior of prompting the user to download the json-response instead.
This is the javascript for making the post:
$.ajax({
url: $("#formRegister").attr("action"),
type: 'POST',
data: JSON.stringify(user),
dataType: 'json',
contentType: 'application/json, charset=utf-8',
traditional: true,
success: function (data) {
alertMessage(data.Message);
},
error: function () {
}
});
This is the ActionMethod receiving the call and returning a JsonResponse:
[HttpPost]
public JsonResult Register(UserRegisterPackage package)
{
ClientAlert alert = new ClientAlert();
if (package.Password != null)
{
//bool success = Removed for simplicity's sake.
bool success = true;
if (success)
{
alert.Message = "Success!";
}
else
{
alert.Message = "Failed to register";
}
}
else
{
alert.Message = "You need to enter a password!";
}
return Json(alert, "text/plain");
}
As I said, when the content type is defined as text/plain the browser shows only the response and when it's not defined it prompts the user to download the json-response instead.
With FF I seem to get an error about:
"event is not defined
event.preventDefault(); "
This could have something to do with the error.. but I need to prevent the form from posting normally. Is this done differently in FF or IE?
Any ideas?

Things to try:
If this $.ajax call is made inside the .click or .submit handler of some anchor or <form> make sure you return false; at the end in order to cancel the default behavior and leave time for your AJAX request to execute. The attr('action') that you are using leaves me to believe that this is the case.
Remove traditional: true parameter, you are sending a JSON request => it is irrelevant.
Make sure there aren't some other javascript errors on your page as they might stop js execution and proceed into normal form submission
Remove all text/plain from your server if you intend to return JSON. It's meaningless to do something like this and it's definitely not where your problem comes from. Simply use return Json(alert);.
So if you are AJAXifying a form you don't even need any JSON requests, simply:
$('#formRegister').submit(function() {
$.ajax({
url: this.action,
type: this.method,
data: $(this).serialize(),
success: function (data) {
alertMessage(data.Message);
},
error: function () {
}
});
return false;
});
and if you intend to send JSON requests then your code seems fine, jsu make sure there aren't some other JS errors.

I faced the same problem where "JsonRequestBehavior.AllowGet" worked great on chrome, but fails on IE. i tried many formats, but below is the only one worked for IE.
return Json(additionalData, "text/html")

I encountered this when using an older version of jQuery.Validate, something to do with a bug in there setting the incorrect dataType.
Make sure you are using the latest version of jQuery.validate

return Json(alert, "text/plain");
Usually Json(alert) should be enough. Can you try with application/json; charset=utf-8 as a content type?

Saving changes to a jQuery sortable table

I have a table where the users are allowed to drag and drop rows in the order they want, and then save them. I have no problem with getting the drag and drop part to work. It's the saving I'm having issues with. I'm sending an Ajax call to a web service which will then make the save. I can't seem to actually catch the request in the web service though.
My JavaScript function looks like so:
$(document).ready(
function () {
$(".sortable").sortable({
update: function () {
serial = $('.sortable').sortable('serialize');
$.ajax({
url: "MyWebService.asmx/SortTable",
type: "post",
data: serial,
error: function () {
alert("theres an error with AJAX");
}
});
}
});
});
The JSON string looks fine from what Firebug is showing me. The web service function is like so:
[WebMethod]
public string SortTable(String[] rows)
{
//SaveChanges();
return "Called!";
}
When I put a breakpoint in there, it never gets hit. When there are no arguments in the function though, it will get hit. I've tried replacing "String[]" with "object" and it still doesn't get hit, which I find odd. What is going on here?

You might need to decorate your web service with the [ScriptService] attribute in order to allow client scripts to invoke it. Also if you are sending a JSON request you need to specify the content type. Another remark is about sending the request as an actual JSON object which could be achieved using the JSON.stringify method (maybe the $('.sortable').sortable('serialize') call already does this, I am not familiar, you just need to ensure that the POSTed value looks like this: [ 'row1', 'row2', ... ]):
$.ajax({
url: 'MyWebService.asmx/SortTable',
type: 'post',
contentType: 'application/json; charset=utf-8',
data: JSON.stringify([ 'row1', 'row2', 'row3' ]),
error: function () {
alert('theres an error with AJAX');
}
});

jQuery Postback with Webforms

We're redevloping a major section of our website and rather than use a 90k AJAX file I'd rather use a 19K jquery script.
I've seen the following articles;
Using jQuery for AJAX with ASP.NET
Webforms
jQuery autocomplete in ASP.NET webforms?
Autocomplete with ASP.Net MVC and
JQuery
The thing I don't get is how to do a postback to a specific method in either the code behind or another class.
I know in ASP.NET-MVC I can post back to a controller / action. How do I call a particular method in WebForms?
Something along the lines of; $.post("class and action", ( param:value}......
Any thoughts, code etc???

It is very easy to call specific methods in code-behind. Here is nice article with all the details by Dave.
Simply declare a method like this:
[WebMethod]
public static string GetDate()
{
return DateTime.Now.ToString();
}
This is all you need in jQuery:
$.ajax({
type: "POST",
url: "PageName.aspx/MethodName",
data: "{}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function(msg, status, xhr) {
// Do something interesting here.
}
});
Caveats:
WebMethod must be on a static method
Must stringify posted data if sending anything (i.e. JSON.stringify(yourDataObject)), will be deserialized according to method parameters
msg is the response, the return result from your method is in the property msg.d