javascript - How can I show a hidden div when a select option is selected?

Question

I want to use plain JavaScript. I have a drop down list (<select> with a number of <option>s). When a certain option is selected I want a hidden div to display.

<select id="test" name="form_select">
   <option value="0">No</option>
   <option value ="1" onClick"showDiv()">Yes</option>
</select>
<div id="hidden_div" style="display: none;">Hello hidden content</div>

Then I'm trying it with this vanilla JavaScript code:

function showDiv(){
   document.getElementById('hidden_div').style.display = "block";
}

I'm guessing my problem is with the onClick trigger in my options but I'm unsure on what else to use?

Answer 1

try this:

function showDiv(divId, element)
{
    document.getElementById(divId).style.display = element.value == 1 ? 'block' : 'none';
}

#hidden_div {
    display: none;
}

<select id="test" name="form_select" onchange="showDiv('hidden_div', this)">
   <option value="0">No</option>
   <option value="1">Yes</option>
</select>
<div id="hidden_div">This is a hidden div</div>