How to trigger jQuery change event in code

Question

I have a change event that is working fine but I need to get it to recurse.

So I have a function that is triggered on change that will "change" other drop downs based on a class selector (notice "drop downS", there could be more than one). This proxy change does not trigger the function and so fails. How can I get it to work?

Code

$(document).ready(function () {
    var activeDropBox = null;

    $("select.drop-box").change(function () {
        var questionId = $(this).attr("questionId");
        var selectedAnswer = $(this).val();
        activeDropBox = this;

        alert(this.questionId);

        $.ajax(
        {
            type: "POST",
            url: answerChangedActionUrl,
            data: { questionId: questionId, selectedValue: selectedAnswer },
            success: function (data) {
                SetElementVisibility(data.ShowElement, questionId);
            }, error: function (XMLHttpRequest, textStatus, errorThrown) {
                alert('XMLHttpRequest:' + XMLHttpRequest.responseText);
                alert('textStatus:' + textStatus);
                alert('errorThrown:' + errorThrown);
            }
        });
    });

    function SetElementVisibility(visible, questionId) {
        // I would like each child to then trigger the change event...
        $(".childOf" + questionId)[visible ? 'show' : 'hide']('slow');
        
        // Suggested code
        //$(".childOf" + questionId + " select").trigger("change");

        if (!visible) {
            $(".childOf" + questionId + " select").attr('selectedIndex', 0);
        }
    }
}

The suggestions so far seem to work, but as the change event triggers an ajax post it now seems to fail here. I'm going to play around with it but that is something for another question I feel.

How can we tell you how to get it to work, when you haven't shown us what it is? — user113716
– user113716, Commented Nov 22, 2010 at 15:58
I thought it was a simple concept and didn't feel code was required. The answers so far seem to have understood my explanation and so I am trying their solutions now. If I don't have any joy I'll post some code. My implementation is actually much more complex. — 4imble
– 4imble, Commented Nov 22, 2010 at 16:05
Sorted it, was a problem with me changing the value after the ajax post. Thanks all for the help. The suggestions posted worked like a charm. — 4imble
– 4imble, Commented Nov 22, 2010 at 16:35

John Hartsock · Accepted Answer · 2010-11-22 15:51:14Z

528

Use the trigger() method

$(selector).trigger("change");

answered Nov 22, 2010 at 15:51

John Hartsock

87.1k23 gold badges135 silver badges146 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Joshua Pinter Over a year ago

Is there any benefit to this over change()? Or is it just preference?

John Hartsock Over a year ago

@JoshPinter no real benefit, more a preference. But definitely easier to abstract as a parameter than a method name.

Kapil Yadav Over a year ago

Setting a value before actually triggering change event is the best way!!

Tim Over a year ago

Latest versions of jQuery (3 atm) will raise a warning when using the deprecated shorthand .change(). You should use .trigger('change') instead.

Yagnesh bhalala Over a year ago

lets celebrate with 500 vote. dear john. its really help ful for me

Amit Shah · Accepted Answer · 2021-09-17 05:00:04Z

58

For me

$('#element').val('...').change()

is the best way.

Note: .change() is deprecated in newer versions use .trigger('change') instead.

edited Sep 17, 2021 at 5:00

Amit Shah

8,2095 gold badges45 silver badges60 bronze badges

answered Jan 30, 2015 at 11:50

Luis Carlos Steffens

5914 silver badges3 bronze badges

5 Comments

Juan Herrera Over a year ago

Yeah!, I like this one

Sergej Fomin Over a year ago

Yes! it allows to choose option on the same time. I think your answer deserves to be the best here.

CodeMantle Over a year ago

This is the only way to trigger change event when programmatically altering the element's value.

Amit Shah Over a year ago

this is now deprecated. all best function essentials for development are getting deprecated... is it to make the developer keep learning new things always?

Peter Pointer Over a year ago

@AmitShah Yeah I think .change() is deprecated in newer versions but .trigger('change') can be used just as well. I think the jQuery team is tired of making shortcuts for functions. It is also easier to find the right function to call when the documentation is a lot smaller.

Frédéric Hamidi · Accepted Answer · 2015-07-20 22:09:46Z

22

The parameterless form of the change() method triggers a change event. You can write something like:

$(document).ready(function() {
    $("#yourInitialElementID").change(function() {
        // Do something here...
        $(".yourDropDownClass").change();
    });
});

edited Jul 20, 2015 at 22:09

answered Nov 22, 2010 at 15:52

Frédéric Hamidi

264k42 gold badges497 silver badges486 bronze badges

1 Comment

Amit Shah Over a year ago

this method is not getting Deprecated.

Geoffrey Hale · Accepted Answer · 2017-06-14 18:34:54Z

15

$(selector).change()

.change()

.trigger("change")

Longer slower alternative, better for abstraction.

.trigger("change")

$(selector).trigger("change")

edited Jun 14, 2017 at 18:34

answered Jan 19, 2016 at 2:00

Geoffrey Hale

11.7k5 gold badges46 silver badges49 bronze badges

Comments

Muhammad Fahad · Accepted Answer · 2016-02-16 09:01:59Z

14

Use That :

$(selector).trigger("change");

OR

$('#id').trigger("click");

OR

$('.class').trigger(event);

Trigger can be any event that javascript support.. Hope it's easy to understandable to all of You.

answered Feb 16, 2016 at 9:01

Muhammad Fahad

1,43217 silver badges15 bronze badges

Collectives™ on Stack Overflow

How to trigger jQuery change event in code

Code

5 Answers 5

5 Comments

5 Comments

1 Comment

.trigger("change")

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

Code

5 Answers 5

5 Comments

5 Comments

1 Comment

.trigger("change")

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related