W3School TIY Editor
W3School 在线教程
改变方向
暗黑模式
运行代码
<!DOCTYPE html> <html> <body> <form id="myForm"> <input type="search" id="mySearch"> </form> <p>单击该按钮可显示搜索字段所属表单的 ID。</p> <button onclick="myFunction()">试一试</button> <p id="demo"></p> <script> function myFunction() { var x = document.getElementById("mySearch").form.id; document.getElementById("demo").innerHTML = x; } </script> </body> </html>