W3School TIY Editor
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<html> <head> <script type="text/javascript"> function alertValue() { var x=document.getElementById("mySelect").selectedIndex; alert(document.getElementsByTagName("option")[x].value); } </script> </head> <body> <form> Select your favorite fruit: <select id="mySelect"> <option value="apple">Apple</option> <option value="orange">Orange</option> <option value="pineapple">Pineapple</option> <option value="banana">Banana</option> </select> <br /><br /> <input type="button" onclick="alertValue()" value="Alert selected value"> </form> </body> </html>