CODEWITHSUNDEEP
javascriptjqueryfunction
Guido Visser
Guido Visser

Reputation: 2309

Stop a function from another function - jQuery

I have a function that is called by a dropdown change. It is possible that the function is running and the user changes the dropdown.

If that happens I want the function that is running to stop.

Ex.

$('.txtCategory').change(function(){
    ajaxPost('para', 'meters').stop(); //doesn't work
    $('#Submit').attr('data-check', 'on');
    $('#Submit').val('Stop Checking');
});

Is this possible?

Thanks in advance!

Greets, Guido

Upvotes: 1

Views: 2911

Answers (4)

VisioN
VisioN

Reputation: 145478

As others stated it is impossible to stop a function out of another function in JavaScript.

However, you may use flags to check whether the Ajax request is now running. For that purposes jQuery has non documented $.activeproperty. You may use it as follows:

$(".txtCategory").change(function() {
    if ($.active > 0)    // if there are more than 0 Ajax requests running
        return false;    // at a time we stop executing the current callback

    ajaxPost("para", "meters");
    $("#Submit").data("check", "on").val("Stop Checking");
});

Upvotes: 0

Onur Topal
Onur Topal

Reputation: 3061

As others mentioned It is not possible to stop/abort a function from another as they both are sync process. On the other hand if you want to stop/abort a AJAX (first A stands for Asynchronous) request you can do that with the help of jQuery's AJAX return object. To do that you can follow the following steps;

First create a global variable to handle AJAX object;

var xhr = null;

When you request by AJAX assign the return object to this variable;

xhr = $.ajax(
    url: "http://someurl.org",
    success: function() { ... }
    );

Now when you need to abort request just a xhr.abort() call should do the trick.

if (xhr != null)
    xhr.abort();

Hope that helps;

Upvotes: 0

Kuldeep Singh
Kuldeep Singh

Reputation: 471

@Guido

I think you want some other things.. Please explain your question in better... I think this isn't what you really want achieve..

Also you can use these

Create a setTimeOut function call and run it every 1000ms so whenever you want to
stop that setTimeOut function you can simple use clearTimeOut to stop it.
it will help you out. if you have still any issues let me know :)

Upvotes: 0

Denys Séguret
Denys Séguret

Reputation: 382474

This isn't possible for a simple reason : your script execution happens on only one thread, only one function can run at a time.

Any callback responding to a local event or to a query won't be called until the current function has finished execution.

Upvotes: 2

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