javascript - select onchange same value - Stack Overflow

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Is there a way to trigger an event if I open a dropdown select, and select the same value WITHOUT clicking away to switch focus?

I tried

1. onblur, but it only works if I make an extra click outside the select.

2. onchange, but it only works if I select a different value.

I need to trigger an event simply if I open the dropdown and select anything, regardless of whether it is the same or different.

<select name='show1' id='show1' onblur='dosomething(this);'>
<option value='1'>One</option>
<option value='2'>Two</option>
</select>

Is there a way to trigger an event if I open a dropdown select, and select the same value WITHOUT clicking away to switch focus?

I tried

1. onblur, but it only works if I make an extra click outside the select.

2. onchange, but it only works if I select a different value.

I need to trigger an event simply if I open the dropdown and select anything, regardless of whether it is the same or different.

<select name='show1' id='show1' onblur='dosomething(this);'>
<option value='1'>One</option>
<option value='2'>Two</option>
</select>

• javascript
• html
• onchange
• onblur

Share Improve this question Follow edited Dec 13, 2012 at 9:49 Uno Mein Ame asked Dec 13, 2012 at 9:30 Uno Mein AmeUno Mein Ame 1,09066 gold badges1616 silver badges3030 bronze badges 4

• it will be better, if you will show us, what you have tried till now. – Ravi Commented Dec 13, 2012 at 9:38
• as i said, i tried onchange and i tried onblur, and none of that works as intended – Uno Mein Ame Commented Dec 13, 2012 at 9:44
• I know, so show us your coding and problem. That will help to know your exact problem. – Ravi Commented Dec 13, 2012 at 9:46
• stackoverflow./questions/647282/… – Alex from Jitbit Commented Dec 26, 2018 at 22:03

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3 Answers 3

Sorted by: Reset to default 3

I think you'd have to use the onClick-event and store the previously selected item in a variable.

Here's a quick example which I think could use some refactoring :-)

    var dropboxOpen = false,
        oldItem     = null;
    function onClick(e) {
        if (dropboxOpen) {
            if (oldItem && oldItem === e.target.value) {
                console.log('same selected');
            }
            oldItem = e.target.value;   
        }        
        dropboxOpen = !dropboxOpen;
     }

http://jsfiddle/vtHPV/

It doesn't matter what library or framework you use, but this is quite simple. You are essentially looking for two things to be true:

1. Test that the control was clicked.

2. Test that a value (any value) has been selected, --or-- is still selected.

Number 2 can be achieved with something like...

var elem = document.getElementById("ddlViewBy");
var value = elem.options[elem.selectedIndex].value;

It's then a simple matter to test that it is non-empty.

If you use jQuery

You can try focus() event.

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