<!DOCTYPE html>charset="utf-8"W3Cschool教程(w3cschool.cn)action="form-action.php"数值: type="number" id="myNumber" name="quantity" requiredtype="submit"点击 "点我" 按钮查看 number 字段是我否为表单的必填部分。onclick="myFunction()"点我id="demo"function myFunction() {var x = document.getElementById("myNumber").required;document.getElementById("demo").innerHTML = x;}