Number of options in the dropdown list(Combobox)
<html> <head> <script type="text/javascript"> function formAction(){ var x=document.getElementById("mySelect") alert(x.length) } </script> </head> <body> <form> <select id="mySelect"> <option>1</option> <option>2</option> <option>3</option> </select> <input type="button" onclick="formAction()" value="How many options in the list?"> </form> </body> </html>