Using jQuery, how can I cancel/abort an Ajax request that I have not yet received the response from?
Source: Tips4all, CCNA FINAL EXAM
Source: Tips4all, CCNA FINAL EXAM
I have a 2.67 GHz Celeron processor, 1.21 GB of RAM on a x86 Windows XP Professional machine. My understanding is that the Android emulator should start fairly quickly on such a machine, but for me it does not. I have followed all instructions in setting up the IDE, SDKs, JDKs and such and have had some success in staring the emulator quickly but is very particulary. How can I, if possible, fix this problem?
Most of the jQuery Ajax methods return an XMLHttpRequest (or the equivalent) object, so you can just use abort().
ReplyDeleteSee the documentation:
abort Method (MSDN). Cancels the current HTTP request.
abort() (MDC). If the request has been sent already, this method will abort the request.
var xhr = $.ajax({
type: "POST",
url: "some.php",
data: "name=John&location=Boston",
success: function(msg){
alert( "Data Saved: " + msg );
}
});
//kill the request
xhr.abort()
UPDATE:
As of jQuery 1.5 the returned object is a wrapper for the native XMLHttpRequest object called jqXHR. This object appears to expose all of the native properties and methods so the above example still works. See The jqXHR Object (jQuery API documentation).
It's an asynchronous request, meaning once it's sent it's out there.
ReplyDeleteIn case your server is starting a very expensive operation due to the AJAX request, the best you can do is open your server to listen for cancel requests, and send a separate AJAX request notifying the server to stop whatever it's doing.
Otherwise, simply ignore the AJAX response.
You can't recall the request but you can set a timeout value after which the response will be ignored. See this page for jquery AJAX options. I believe that your error callback will be called if the timeout period is exceeded. There is already a default timeout on every AJAX request.
ReplyDeletemeouw's solution is correct, but if you're are interested in more control then you could try the Ajax Manager plugin for jQuery.
ReplyDeleteSave the calls you make on a array, then call xhr.abort() on each.
ReplyDeleteHUGE CAVEAT: you can abort a request, but that only the clientside, the server side could still be running the request. If you are using something like PHP/ASP with session data, the session data is locked until the ajax has finished. So to allow the user to continue browsing the website, you have to call session_write_close().