Onchange event on checkbox always shows this.value = on

Question

Onchange event on checkbox always shows this.value = on

The input checkbox of type type when the event is triggered is onchange

this.value

always set to on

, even if the checkbox is checked, in which case I expect it to beoff

Is this the intended behavior?

<input type="checkbox" onchange="alert(this.value)">

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+3

javascript html checkbox

laggingreflex Apr 29. At 1:09 am

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1 answer

Santiago Hernández · Accepted Answer · 2015-04-29T01:11:29+0000

short answer: don't use value

to check the check on checkbox, use checked

instead

<input type="checkbox" onchange="alert(this.checked)">

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and in case you are wondering why this value is always "on", there is a spec for the HTML5 spec:

default / on

On getting, if an element has a value attribute, it must return that attribute value; otherwise, it should return the string "on" . On customization, it should set the element's value attribute to a new value.

http://www.w3.org/TR/html5/forms.html#dom-input-value-default-on

Onchange event on checkbox always shows this.value = on

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