Tryit Editor v1.8

Source Code:
<!DOCTYPE html> <html> <head> <script> function disable() { document.getElementById("mySelect").disabled=true; } function enable() { document.getElementById("mySelect").disabled=false; } </script> </head> <body> <form> <select id="mySelect"> <option>Apple</option> <option>Pear</option> <option>Banana</option> <option>Orange</option> </select> <br><br> <input type="button" onclick="disable()" value="Disable list"> <input type="button" onclick="enable()" value="Enable list"> </form> </body> </html>
Result:
W3Schools.com - Try it yourself