I have a problem wit a $.post request. No errors, but the return is empty. Before I start bugging the server admin, of who the service is, with this problem. I want to make sure I did not make any mistake myself.
Below the code I'm using:
var post_data = JSON.stringify({'str_action':'log_element', 'int_id':'TEST', 'str_value':'EMPTY'});
$.post('http://url/', post_data, debug_return_data);
function debug_return_data(data)
{
alert(data);
}
Problem is that the returned data in the alert is empty. Did I make any mistake in my code?
Thanks in advance.
The Ajax call looks correct, check the response in firebug or chrome dev tools to make sure the server is actually returning data.
If you are making the AJAX call to anther server other than the one in the address bar it will be blocked as a cross-domain call. Use JSONP if you want to do this:
http://devlog.info/2010/03/10/cross-domain-ajax/
$.post('http://url/', post_data, function(data)
{
alert(data);
});
this is in the jquery documentation
Related
Its sounds simple, but let me explain.
I make ajax calls to update the body content and I want to alert if the updating fails in the client side, I mean after receiving response from ajax and if it fails of anycase.
$(".body").html(response_from_ajax) ;
so I tried with my basic knowledge like this
if ( ! $(".body").html(response_from_ajax) )
{
alert('error');
}
this is not working.
I don't think it can fail after getting the content from ajax call because you are just setting the html of the div. However, you can simply define the error method in the ajax call to make sure that data is recieved from the ajax call.
On one of my pages I have "tracking.php" that makes a request to another server, and if tracking is sucessful in Firebug Net panel I see the response trackingFinished();
Is there an easy way (built-in function) to accomplish something like this:
If ("tracking.php" responded "trackingFinished();") { *redirect*... }
Javascript? PHP? Anything?
The thing is, this "tracking.php" also creates browser and flash cookies (and then responds with trackingfinished(); when they're created). I had a JS that did something like this:
If ("MyCookie" is created) { *redirect*... }
It worked, but if you had MyCookie in your browser from before, it just redirected before "track.php" had the time to create new cookies, so old cookies didn't get overwritten (which I'm trying to accomplish) before the redirection...
The solution I have in mind is to redirect after trackingFinished(); was responded...
I think the better form in javascript to make request from one page to another, without leaving the first is with the ajax method, and this one jQuery make it so easy, you only have to use the ajax function, and pass a little parameters:
$.post(url, {parameter1: parameter1value, param2: param2value})
And you can concatenate some actions:
$.post().done(function(){}).fail(function(){})
And isntead of the ajax, you can use the $.post that is more easy, and use the done and fail method to evaluate the succes of the information recived
As mentioned above, AJAX is the best way to communicate between pages like this. Here's an example of an AJAX request to your track.php page. It uses the success function to see if track.php returned 'trackingFinished();'. If it did then it redirects the page 'redirect.php':
$.ajax({
url: "track.php",
dataType: "text",
success: function(data){
if(data === 'trackingFinished();'){
document.location = 'redirect.php';
}
}
});
The example uses JQuery.
i am really banging my head here for more then a day, i am trying to send a request and get the response from another site. i'm doing it with jsonp (from the obvious reason). but the response is not a JavaScript function definition, so it keeps failing.
can anyone in this planet help me get the response the right way.
i attached the code i wrote, again: because the response is not in json it's not working. (try to run it yourself and you'll see).
any suggestions?
<script>
function test()
{
$.ajax({
dataType: 'jsonp',
jsonp: 'jsonp_callback',
url: 'https://www.facebook.com/ajax/typeahead/first_degree.php?viewer=1000009843914&token=1-1&filter[0]=user&options[0]=pending_request&lazy=1&token=v7&stale_ok=1&__a=1&__user=1000009843914& viewer=1000009843914',
});
}
function jsonp_callback(data)
{
var val=JSON.stringify(data);
myString = val.slice( 11 );
$('#container').html(myString);
/*for (;;);*/
}
test();
</script>
The server must be programmed to include the JSONP callback within its script file. If it only knows to return JSON, it will have no effect when the dynamic script tag is inserted into the page since JSON can at most provide an object--but it won't go anywhere unless the same file calls the function. In this way, it is different from Ajax, since a dynamically inserted script tag can only interact with your own code if it knows to call one of your functions. Just as an example, it might return:
jsonp_callback({facebooKData:[...]});
You should investigate how the Facebook API supports JSONP (not just JSON) for whatever you are trying to do. Typically APIs will accept a "callback" variable to determine which callback function it should use (which jQuery handles for you).
If you copy and past the following url to your browser:
http://finance.google.com/finance/info?client=ig&q=MUTF_CA%3ATDB900
it will output an string no problem. (that is what i wanted to retrieve from the following ajax call)
But if i do the following:
this.getQuote = function() {
$.get('http://finance.google.com/finance/info?client=ig&q=MUTF_CA%3ATDB900', callback);
}
var callback = function(data){
alert(data);
}
It gave me an "500 Internal Server Error". I checked using firebug console.
Did i do something wrong in the ajax call?
Thanks.
As Shadow_boi already guessed, the problem is due to the same origin policiy, which always applies to ajax requests. You need to use JSONP to fix the problem.
See this fiddle for solution: http://jsfiddle.net/cb9c3/
I had a problem with jquery's post api.
$(".MGdi").click(function () {
id=$(this).attr("rel")
$.post( 'Mdeger.asp?cmd=MG', { id: id, drm: $(this).html()} ,
function( data ) {
var $response=$(data);
var snc = $response.find('#snc').html();
alert(snc);
},"application/x-www-form-urlencoded");
});
Another way is:
$(".Pasif").click(function () {
id=$(this).attr("rel")
$.post( 'Mdeger.asp?cmd=Pasif', { id: id, drm: $(this).html()} ,
function( data ) {
$(this).html(data);
alert(data)
},"application/x-www-form-urlencoded");
});
Everything is OK on serverside but clientside's success function does nothing.
Even basic codes like alert("hoho"); success not triggering.
this usually happens when respond couldn't be parsed. you should check the respond using firebug or similar debugging tool.
especially the methods that expects json data, strictly validates the respond and if there is anything invalid it just does nothing, no-error, no-warning, no-exception.
when your callback function doesn't run, you should suspect that your respond isn't correct.
// Türkçe özet
uzun lafın kısası dönüş değerinde bir terslik varsa dönüş fonksiyonu çalışmayacaktır. sunucudan gelen değerleri iyice kontrol etmekte fayda var. jquery dönüş değerinde veya dönüş fonksiyonunda bir hata olursa seni uyarmadan işi sonlandırıyor.
I had this problem as well. It turns out I was making an AJAX call to the same domain, but on a different port, which is not allowed (for security reasons) in Javascript.
See this relevant question for more info:
How do I send an AJAX request on a different port with jQuery?
I was very surprised that the AJAX call would POST/GET to the server, (which I was able to verify by looking at the server log) but that the response was never read. I would have thought that both sending and receiving would be disallowed.
I had this error too, and that was a stupid problem : I set dataType to "json" in my JS, but the page called was returning plain HTML. And this cause to not fire the success function at all.