简单教程
提交运行
代码编辑器:
<form action="/dy/html/getpost"> 搜索: <input type="search" id="mySearch" name="filter" required> <input type="submit"> </form> <p>点击 "点我" 按钮查看在表单提交前搜索字段是否为必填字段</p> <button onclick="myFunction()">点我</button> <p id="demo"></p> <script> function myFunction() { var x = document.getElementById("mySearch").required; document.getElementById("demo").innerHTML = x; } </script>
运行结果: