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<!DOCTYPE html> <html> <body> <form id="frm1" action="form_action.asp"> First name: <input type="text" name="fname" value="Donald"><br> Last name: <input type="text" name="lname" value="Duck"><br><br> <input type="submit" value="Submit"> </form> <p>Click "Try it" to display the number of elements the form:</p> <button onclick="myFunction()">Try it</button> <p id="demo"></p> <script> function myFunction() { var x = document.getElementById("frm1").length; document.getElementById("demo").innerHTML = x; } </script> </body> </html>