Option index 屬性
Option 對(duì)象定義和用法
index 屬性可返回下拉列表中選項(xiàng)的索引位置。
The index starts at 0.
語(yǔ)法
設(shè)置 index 屬性:
optionObject.index=integer
返回 index 屬性:
optionObject.index
瀏覽器支持
所有主要瀏覽器都支持 index 屬性
實(shí)例
實(shí)例
本例可返回下拉列表中所選的選項(xiàng)的索引位置:
<html>
<head>
<script>
function displayResult()
{
var x=document.getElementById("mySelect").selectedIndex;
var y=document.getElementById("mySelect").options;
alert("Index: " + y[x].index + " is " + y[x].text);
}
</script>
</head>
<body>
<form>
Select your favorite fruit:
<select id="mySelect">
? <option>Apple</option>
? <option>Orange</option>
? <option>Pineapple</option>
? <option>Banana</option>
</select>
</form>
<button type="button" onclick="displayResult()">Display index</button>
</body>
</html>
<head>
<script>
function displayResult()
{
var x=document.getElementById("mySelect").selectedIndex;
var y=document.getElementById("mySelect").options;
alert("Index: " + y[x].index + " is " + y[x].text);
}
</script>
</head>
<body>
<form>
Select your favorite fruit:
<select id="mySelect">
? <option>Apple</option>
? <option>Orange</option>
? <option>Pineapple</option>
? <option>Banana</option>
</select>
</form>
<button type="button" onclick="displayResult()">Display index</button>
</body>
</html>
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Option 對(duì)象
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