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<html> <head> <script type="text/javascript"> function getIndex() { var x=document.getElementById("mySelect") alert(x.selectedIndex) } </script> </head> <body> <form> Select your favorite fruit: <select id="mySelect"> <option>Apple</option> <option>Orange</option> <option>Pineapple</option> <option>Banana</option> </select> <br /><br /> <input type="button" onclick="getIndex()" value="Alert index of selected option"> </form> </body> </html>