In the example below, I'm trying to populate an input with the contents of the option.data-foo attribute. I feel like this close... but I've got something back-to-front somewhere... Any thoughts?
My code :
function updateText(type) {
var id = type+'Text';
document.getElementById(id).data-foo = document.getElementById(type).value;
}
<form id="example" name="example">
<select id="sensor" onchange="updateText('sensor')">
<option value="Jval" data-foo="Jfoo">Joption</option>
<option value="Kval" data-foo="Kfoo">Koption</option>
</select>
<br />
<input type="text" value="" id="sensorText" />
</form>
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