javascript案例 - W3xue在线HTML/CSS/JS运行工具

​x
 
<html>
<head>
<script type="text/javascript">
function alertDefaultSelected()
{
  var x=document.getElementById("mySelect").selectedIndex;
  var y=document.getElementsByTagName("option");
  alert("Is " + y[x].text + " selected by default? " + y[x].defaultSelected);
}
</script>
</head>
<body>
​
<form>
Select your favorite fruit:
<select id="mySelect">
  <option>Apple</option>
  <option>Orange</option>
  <option selected="selected">Pineapple</option>
  <option>Banana</option>
</select>
<br />
<br />
<input type="button" onclick="alertDefaultSelected()" value="Is the chosen fruit selected by default?">