表單提交的兩種方式submit,onsubmit(當滿足條件之後才提交)
阿新 • • 發佈:2018-12-21
在form標籤設定onsubmit屬性,當return true之後才提交:
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Insert title here</title> </head> <body> <script> function judge() { var element=document.getElementById("username").value; if(element == "") { alert("使用者名稱不能問空!"); return false; } else return true; } </script> <h1 align="center">註冊頁 面</h1> <form action="RegisterValidate" method="post" onsubmit="return judge()"> <p align="center"> 用 戶 名:<input type="text" id="username" name="username" placeholder="輸入20個字元以內"> </p> <p align="center"> 輸入密碼:<input type="text" name="password" placeholder="輸入20個字元以內"> </p> <p align="center"> 確認密碼:<input type="text" name="confirmPassword" placeholder="重新輸入密碼"> </p> <p align="center"> <input type="submit" value="註冊"> <input type="reset" value="重置"> </p> </form> </body> </html>