Mega Code Archive
Select selectedIndex
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The selectedIndex property returns the index number of the selected option in that instance of a select box.
If this property is used to access a multiple select box, it will return the index number of the first selected item.
<html>
<form name="myForm">
<select name="mySelect" onChange='alert(mySelect.selectedIndex)'>
<option value=A>AA</option>
<option value=B>BB</option>
<option value=C>CC</option>
<option value=D>DD</option>
</select>
</form>
</html>
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