编辑代码:
查看结果 »
试一试 - ©
w3ii.com
<!DOCTYPE html> <html> <body> <form id="myForm"> <textarea id="myTextarea" rows="4" cols="50"> At w3schools.com you will learn how to make a website. We offer free tutorials in all web development technologies. </textarea> </form> <p>Click the button to display the id of the form the text area belongs to.</p> <button type="button" onclick="myFunction()">Try it</button> <p id="demo"></p> <script> function myFunction() { var x = document.getElementById("myTextarea").form.id; document.getElementById("demo").innerHTML = x; } </script> </body> </html>