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<!DOCTYPE html> <html> <body> <form id="myForm" action="demo_keygen.asp" method="get"> Username: <input type="text" name="usr_name"> Encryption: <keygen id="myKeygen" name="security"> <input type="submit"> </form> <p>Click the "Try it" button to return the id of the form the keygen field belongs to.</p> <button onclick="myFunction()">Try it</button> <p id="demo"></p> <script> function myFunction() { var x = document.getElementById("myKeygen").form.id; document.getElementById("demo").innerHTML = x; } </script> </body> </html>