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HTMLSelectElement.selectedIndex

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The HTMLSelectElement.selectedIndex is a long that reflects the index of the first selected <option> element. The value -1 indicates that no element is selected.

Syntax

var index = selectElem.selectedIndex;
selectElem.selectedIndex = index;

Example

HTML

<p id="p">selectedIndex: 0</p>

<select id="select">
  <option selected>Option A</option>
  <option>Option B</option>
  <option>Option C</option>
  <option>Option D</option>
  <option>Option E</option>
</select>

JavaScript

var selectElem = document.getElementById('select')
var pElem = document.getElementById('p')

// When a new <option> is selected
selectElem.addEventListener('change', function() {
  var index = selectElem.selectedIndex;
  // Add that data to the <p>
  pElem.innerHTML = 'selectedIndex: ' + index;
})

Specifications

Specification Status Comment
WHATWG HTML Living Standard
The definition of 'HTMLSelectElement' in that specification.
Living Standard No change since the latest snapshot, HTML5.
HTML5
The definition of 'HTMLSelectElement' in that specification.
Recommendation Initial definition, snapshot of WHATWG HTML Living Standard.

Browser compatibility

 
Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support ? ? ? ? ?
Feature Android Chrome Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
Basic support ? ? ? ? ? ? ?

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 最終更新者: Druzion,