如何在JSP页面中重新加载页面时更改标签的文本？ [英] How to change the text of a label when a page is reloaded in JSP page?
本文介绍了如何在JSP页面中重新加载页面时更改标签的文本？的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我是servlets的新手。我有一个servlet，我在其中更新数据库。单击提交按钮后，我想显示一条消息，告知更新是否成功。为此，我打算放一个标签，但标签标签没有像价值，可见等属性。我怎么能这样做？这是我的servlet代码：
I am new to servlets. I have a servlet that i update the database in it. After clicking submit button, i want to show a message that tells whether update is succesfull or not. For this i am planning to put a label but label tag has no property like value, visible etc. How can i do that? Here is my code of servlet:
protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//System.out.println("editservlet");
try
{
connect();
int result=-1;
PreparedStatement checkDB = (PreparedStatement) con.prepareStatement(
"UPDATE users set username=?,password=?,name=?,surname=?,phone=?,address=?," +
"email=? where username=?");
checkDB.setString(8,request.getParameter("tUserName"));
checkDB.setString(1,request.getParameter("tUserName"));
checkDB.setString(2,request.getParameter("tPassword"));
checkDB.setString(3,request.getParameter("tName"));
checkDB.setString(4,request.getParameter("tSurName"));
checkDB.setString(5,request.getParameter("tPhone"));
checkDB.setString(6,request.getParameter("tAddress"));
checkDB.setString(7,request.getParameter("tEmail"));
result= checkDB.executeUpdate();
if(result>0)
//SHOW THE MESSAGE THAT TELLS UPDATE SUCCESFUL
}
catch(Exception e)
{
e.printStackTrace();
//SHOW THE MESSAGE THAT UPDATE UNSUCCESFUL
}
}
任何人都可以帮我这个吗？谢谢
Can anyone help me with this? Thanks
推荐答案
避免从servlet中打印出HTML。它已被弃用。
Avoiding printing out HTML from your servlets. It's deprecated.
创建一个JSP页面，例如 SignupStatus.jsp
Create a JSP page, say SignupStatus.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" %>
<html>
<head>
<title>Signup Status</title>
</head>
<body>
<p>Hi <b>${username}<b>,<br />
Your signup ${statusMsg}
</p>
</body>
</html>
然后将 servlet 更改为
protected void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// request attributes to be sent to JSP
String username = null;
StringBuilder statusMsg = new StringBuilder();
try
{
connect();
int result=-1;
PreparedStatement checkDB = (PreparedStatement) con.prepareStatement(
"UPDATE users set username=?,password=?,name=?,surname=?,phone=?," +
"address=?,email=? where username=?");
// set username value
username = request.getParameter("tUserName");
// set username as request attribute
request.setAttribute("username", username);
checkDB.setString(8,username);
checkDB.setString(1,username);
checkDB.setString(2,request.getParameter("tPassword"));
checkDB.setString(3,request.getParameter("tName"));
checkDB.setString(4,request.getParameter("tSurName"));
checkDB.setString(5,request.getParameter("tPhone"));
checkDB.setString(6,request.getParameter("tAddress"));
checkDB.setString(7,request.getParameter("tEmail"));
result= checkDB.executeUpdate();
if(result>0)
statusMsg.append("was successful!"); // set a success message
}
catch(Exception e)
{
e.printStackTrace();
// set a failure message along with error details
statusMsg.append("failed with the error: ").append(e.getMessage());
}
// set status message as request attribute
request.setAttribute("statusMsg", statusMsg.toString());
// forward request (along with its attributes) to the status JSP
RequestDispatcher rd = response.getRequestDispatcher("SignupStatus.jsp");
rd.forward(request, response);
}
这篇关于如何在JSP页面中重新加载页面时更改标签的文本？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
