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Getting data from a webservice c# javascript ajax

I really need help with getting data from my webservice, but all I get is "internal server error". The desired result is to be able to have a webservice return data to my javascript function.
Yesterday I was successfully able to call a webservice, but not able to get data from it.
Below is my javascript code which I understand is executed on the client
function Test(myid) {
var projects;
var opt = document.getElementById(myid);
var constring = '<%=this.ConnectionText %>';
document.getElementById("Text1").value = opt.value;
$.ajax({
type: 'GET',
url: 'Overview.aspx/ExecuteSelectListBox',
contentType: "application/json;charset=utf-8",
dataType:"json",
success: function (data) {
projects = data.d;
},
error: function (requeset, status, error) {
alert( error);
}
});
}
If succesful then projects should become "hello world"
Below is my C# code which I have understood is executed on the server.
However, I dont think my function on the server is called at all. If I replace Overview.aspx with something else I get "not found" from server instead of "internal server error".
But the "executelistbox" itself I can call whatever and I still get "internal server error" and not "not found".
[System.Web.Script.Services.ScriptService]
public class AjaxWebService : System.Web.Services.WebService
{
[System.Web.Services.WebMethod(EnableSession = true)]
/**************************************************
*** Returns a datatable with projectnames. ***
*************************************************/
public static string ExecuteSelectListBox()
{
return "hello world";
}
}
So the desired problem is to be able to retrieve data from a webservice written in c#. Both c# and javascript are actually part of the same webpage in this example. I keep it minimalistic. I hope others can use this too, as a basic example how youre able to get data from your webserver. In the future I will make database calls from the server and send back to the client, but I cannot even think about this now, as I even cant get "hello world" to work :)
I would be so grateful if anyone could help!! I tried posted this before but was shut "on hold".

I would take a look at the following tutorial and use WebApi instead of System.Web.WebService. You are making it yourself rather difficult.
http://www.asp.net/web-api/overview/getting-started-with-aspnet-web-api/tutorial-your-first-web-api
At the moment you're requesting Json, but im not sure whether you are actually returning Json, but perhaps xml?

$.ajax POST call to ServiceStack webservice, parameter not arriving

I am trying to learn how to program a web service with ServiceStack and call it via ajax in JavaScript. I did this by watching the pluralsight movies and I think I almost figured it out how to do that except for passing data as parameters with a service call.
I try to call the service with this ajax-call:
var request = { };
request.Amount = 32;
$.ajax({ type: 'POST',
contentType: 'application/jsonp; charset=utf-8',
url: "http://localhost:1879/entry",
dataType: 'jsonp',
data: {request: request},
success: function(result){
alert(result.Id);
}});
The service looks like this:
public class EntryService : Service
{
public object Post(Entry request)
{
return new EntryResponse() { Id = request.Amount };
}
}
[Route("/entry", "POST")]
public class Entry
{
public int Amount { get; set; }
}
public class EntryResponse
{
public int Id { get; set; }
}
I expect the alert in the callback to show the number 32, but it shows the number 0. And when I debug my service I see that request.Amount is 0 as well, so I think I do something wrong at the Ajax service call but I cannot figure out what. So I wonder what I am doing wrong here.

author of that Pluralsight course here. Hopefully I can help you.
First thing you should do is make sure the API is working correctly.
Go to this: http://localhost:1879/entry
In your web browser you should see a page displayed that has information about the service. If you don't your URL is wrong or ServiceStack is configured wrong.
Assuming the URL is correct, all you should need to do is wrap your data in JSON.Stringify().
When you do a post, the data has to be in JSON format as a JSON string. You are currently sending a JSON object.
Also, most likely you can drop the localhost bit off your url in the $.ajax call and just do "entry"

You can not do a post with JsonP. If you are trying to do a cross domain POST you need to look into cors and make sure that is enabled for the the service you are POSTing to.
Post data to JsonP

I only used jsonp cause I read and hoped that it could be the solution for my problem. But based on your explanation I shouldn't need it, so I changed my code to this:
var request = { };
request.Amount = 32;
$.ajax({ type: 'POST',
contentType: 'application/json; charset=utf-8',
url: "http://localhost:1879/json/reply/Entry",
dataType: 'json',
data: request,
success: function(result){
alert(result.Id);
},
error: function(xhr, ajaxOptions, thrownError){
alert("Failure!");
alert(xhr.status);
alert(thrownError);
}});
First I had this call without the error part and nothing happened, no alert, no error, nothing. So I assumed the error was consumed instead of being showed, so I added the error callback and my assumption seemed to be right. Now I get 3 alerts and the last 2 alerts shows "400" and "bad request".
I searched on those errors and tried but none of the possible solutions I found fixed my problem. I tried 2 urls: /json/reply/Entry and /entry after the localhost part but both didn't work. So what am I doing wrong?

Cross Domain jQuery Ajax Using C# and WFC

I have a small webservice written in C# and WCF.
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[System.Web.Script.Services.ScriptService]
public class Service1 : System.Web.Services.WebService
{
[WebMethod]
public string HelloWorld()
{
return "Hello Worlds";
}
}
I have a little jQuery code;
$.support.cors = true;
$.ajax({
type: "POST",
url: "http://localhost:61614/Service1.asmx/HelloWorld",
data: '{}',
dataType: "json",
success: function (msg) {
alert(0);
}, error: function (a, b, c) { alert("Err:" + c );
}
});
This calls the webservice. There are no problems making the call, but it errors out on the return.
The webservice is in one application, and the Web page is simply an HTML page on it's own. Eventually, the HTML will be used within PhoneGap.
I have tried all sorts of things.
Adding in contentType: "application/json; charset=utf-8", causes the whole call to fail.
Using dataType: 'jsonp" causes call to fail.
Basically, the above calls the WS but errors out on return which is weird.
My requirement is that I need to return a JSON object from the webservice, and it has to work in Safari.
Does anyone have complete sample code of a JSONP call?

From jQuery getJSON:
If the URL includes the string "callback=?" (or similar, as defined by the server-side API), the request is treated as JSONP instead. See the discussion of the jsonp data type in $.ajax() for more details.
In order for your request to be treated as a JSONP request, you need to include callback=? in your URL. This tells jQuery to create a callback function and pass the name of that function as the callback parameter to your server.
In the server-side code, your method must then return JSON code wrapped, or padded, with the name of the JavaScript function passed in as the callback parameter in the query string.
Essentially, what you're doing is returning JavaScript to the client browser, which runs immediately, and invokes a function already defined in the context of the page.
JavaScript:
$.getJSON("http://localhost:61614/Service1.asmx/HelloWorld?callback=?",
function(data) {
// alert raw JSON data
alert(JSON.stringify(data));
// access the "say" property and alert it
alert(data.say);
}
);
Server-Side:
This is a crude version of what you'd need to do on the server-side:
// get the callback parameter value and assign to the String callback
...
return callback + "( { 'say' : 'HelloWorld' } );";
Further technical explanation of what is happening under the hood:
While this is not something you need to know today, this may help you understand more about how jQuery is implementing JSONP.
This evaluates to something that might look like this:
return "jquery43214321432143242({'say':'HelloWorld'});"
where jquery43214321432143242 is the random name given for your success callback function. Again, since the returned text is returned using text/javascript, it runs immediately, passing the {'say':'HelloWorld'} object in as a parameter to the function.
The resulting output should be an alert message representing the raw JSON, and the words "HelloWorld", pulled from the .say property.

Migrating ASMX Service to WCF Service - AJAX Post

I have a asp.net asmx service and i would like to convert it to a wcf service.
I'm having problems calling the wcf service from jquery ajax POST request with parameters.
if i call the WCF service without parameters or pass the parameter in a json format it works OK.
When executing the below jquery post to the wcf service i get error 500.
Please note , i cannot change the way the jquery request is made.
Original ASMX Service:
[WebMethod(EnableSession = true)]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public void SendStatus(string param1, string param2)
{
..................
}
jQuery POST:
var d = { param1: 1, param2: 2 };
$.ajax({
type: "POST",
url: "/Service1.asmx/SendStatus",
data: d,
success: function () { }
});
NEW WCF Service:
[OperationContract]
[WebInvoke]
public void SendStatus(string param1, string param2)
{
}
jQuery POST:
var d = { param1: 1, param2: 2 };
$.ajax({
type: "POST",
url: "/Service2.svc/SendStatus",
data: d,
success: function () { }
});

-- EDIT --
I recall this issue drove me nuts once before, so I went back for another look. Sure enough ... Given the requirement that the Javscript remain as written, I maintain that this is literally impossible with the current release of WCF. Consider the following points:
1) You need to use webHttpBinding, because that's the only binding that supports REST style services (basicHttpBinding and WSHttpBinding both use SOAP wrappers). (ref. here: BasicHttpBinding vs WsHttpBinding vs WebHttpBinding)
2) The AJAX call as written in this question uses a content-type of "application/x-www-form-urlencoded" (you can confirm this using Fiddler).
3) You can also confirm that WCF throws an exception before the service method even gets invoked. The exception is as follows:
The body style 'Bare' is not supported by 'WebScriptEnablingBehavior'. Change the body style to be 'WrappedRequest'.
But "bare" body style is Microsoft-speak for a REST request using basic parameters (ie, not "wrapped" in JSON or XML). That is, there is no possible configuration that would allow WCF to handle this specific AJAX request. You can even implement your own WebContentTypeMapper, and it still won't work. This guy is on to them: http://visualstudio.uservoice.com/forums/121579-visual-studio/suggestions/2473190-consider-making-the-system-servicemodel-channels-r
My conclusion is that (given you can't use MVC, which would make this a piece of cake), you need to somehow route this request to a basic .ASPX page, and use the trusty old Webforms methods (Page.IsPostBack, Request.Params["param1"], etc).
-- END EDIT --
Per the other thread above, looks like there are a few parameters you need to add/fix in your AJAX call:
...
dataType: 'json',
contentType: 'application/json; charset=utf-8',
data: JSON.stringify(d)
...

If you can't change the client-side code, you should not migrate these endpoints from ASMX to WCF. WCF uses a different, less-flexible serializer than ASMX and it's likely that you'll run into trouble that can only be resolved by changing how data is sent, received, and/or handled on the client-side.
If you're willing to deal with that turmoil anyway, a much better migration path would be waiting until ASP.NET Web API is shipped and moving to it. If you move to WCF now, you'll just be behind again later this year when Web API is released.

I think you have to pass string parameter values in double quotes (""). Like this:
var d = { param1: "1", param2: "2" };
$.ajax({
type: "POST",
url: "/Service2.svc/SendStatus",
data: d,
success: function () { }
});
Hope this will work.
500 error code means parameter values didn't match with required values.

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');
}
});