ViewUser.jsp
<%
String username = (String) session.getAttribute("name");
%>
<%@ page contentType="text/html; charset=utf-8" language="java"
import="java.sql.*" errorPage=""%>
<%@page
import="com.oreilly.servlet.*,java.sql.*,java.lang.*,java.text.SimpleDateFormat,java.util.*,java.io.*,javax.servlet.*, javax.servlet.http.*"%>
<%@page import=" java.security.MessageDigest"%>
<%@page import=" java.security.*"%>
<%@page import="javax.crypto.*"%>
<!DOCTYPE html>
<!--[if lt IE 7]> <html class="lt-ie9 lt-ie8 lt-ie7" lang="en"> <![endif]-->
<!--[if IE 7]> <html class="lt-ie9 lt-ie8" lang="en"> <![endif]-->
<!--[if IE 8]> <html class="lt-ie9" lang="en"> <![endif]-->
<!--[if gt IE 8]><!-->
<html lang="en">
<!--<![endif]-->
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
<title>View User</title>
<link rel="stylesheet" href="home.css">
<!--[if lt IE 9]><script src="//html5shim.googlecode.com/svn/trunk/html5.js"></script><![endif]-->
</head>
<body>
<br>
<br>
<p class="user">
Welcome <%=username%></p>
<header>
<nav>
<ul class="nav">
<li><a href="Admin_Home.jsp" class="icon home"><span>Home</span></a></li>
<li><a href="ViewUser.jsp">View User</a></li>
<li><a href="ViewData.jsp">View Data</a></li>
<li><a href="index.html">Logout</a></li>
</ul>
</nav>
</header>
<br>
<br>
<br>
<marquee class="head1" behavior="scroll" direction="left">Information Of Users...! </marquee>
<div id="page" style="margin-top: 25px;"></div>
<div id="content">
<div style="clear: both;"> </div>
<div style="width: 100%; margin-top: 40px;">
<table class="head1"
style="border: 4px solid black; border-spacing: 15px; border-collapse: collapse; width: 60%; border-radius: 10px; box-shadow: #000 2px 2px 2px 2px; margin: 80px;">
<tr style="color: white;">
<th
style="padding: 3px; width: 480px; margin-top: 0px; margin-left: -10px; padding-left: 00px;">USERNAME</th>
<th
style="padding: 3px; width: 220px; margin-top: 0px; margin-left: -10px; padding-left: 00px;">PASSWORD</th>
<th
style="padding: 3px; width: 230px; margin-top: 0px; margin-left: -10px; padding-left: 00px;">PHONE NO.</th>
<th
style="padding: 3px; width: 230px; margin-top: 0px; margin-left: -10px; padding-left: 00px;">EMAIL</th>
<th
style="padding: 3px; width: 230px; margin-top: 0px; margin-left: -10px; padding-left: 00px;">Remove User</th>
</tr>
<%
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/db", "root", "root123");
Statement st = con.createStatement();
ResultSet rs = st.executeQuery("SELECT username,password,phone,address FROM newuser");
while (rs.next()) {
username=rs.getString("username");
String password = rs.getString("password");
String address = rs.getString("address");
String phone = rs.getString("phone");
%>
<tr>
<td style="padding: 10px; height: 60px;"><span
style="margin-left: 5px;"><%=username%></span></td>
<td style="padding: 3px; height: 60px;"><span
style="margin-left: 5px;"><%=password%></span></td>
<td style="padding: 3px; height: 60px;"><span
style="margin-left: 5px;"><%=phone%></span></td>
<td style="padding: 3px; height: 60px;"><span
style="margin-left: 5px;"><%=address%></span></td>
<td style="padding: 3px; height: 60px;"><span
style="margin-left: 5px;"><a href="RemoveUser.jsp"
<%=username%>>Remove</a></span></td>
</tr>
<%
}
} catch (Exception e) {
}
%>
</table>
</div>
<div style="clear: both;"> </div>
</div>
</body>
</html>
RemoveUser.jsp
<%
String username = (String) session.getAttribute("name");
%>
<%@page
import="com.oreilly.servlet.*,java.sql.*,java.lang.*,java.text.SimpleDateFormat,java.util.*,java.io.*,javax.servlet.*, javax.servlet.http.*"
errorPage="Error.jsp"%>
<%@page import=" java.security.MessageDigest"%>
<%@page import=" java.security.*"%>
<%@page import="javax.crypto.*"%>
<%
username = request.getParameter("username");
Connection con = null;
try {
try {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/db", "root", "root123");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
Statement st = con.createStatement();
int x = st.executeUpdate("delete from newuser where username='" + username + "'");
if (x != 0) {
out.println("Success..!!");
} else {
out.println("Failed..!!");
}
} catch (Exception e) {
out.println(e);
}
%>
您好， 我在删除用户时遇到问题。它显示执行后输出失败。我认为它不需要来自viewUser的用户名。请帮我。 查询没问题，数据库连接仍然存在问题，取用用户名并删除它。 谢谢 ！
答案 0 :(得分：0)
还有其他例外吗？ 因为x = 0表示更新已执行，但没有发现删除，请注意mysql区分大小写，还需要提交操作。
答案 1 :(得分：0)
在Remove.jsp页面中：
... 的
username = request.getParameter("username");
没有任何参数是＆＃39;用户名＆＃39;，您需要在?之后的删除链接中设置参数Remove.jsp?<%=username%>
在ViewUser.jsp页面中：
... 的
<td style="padding: 3px; height: 60px;">
<span style="margin-left: 5px;">
<a href="RemoveUser.jsp"<%=username%>>Remove</a>
</span>
</td>
应该修改：
... 的
<td style="padding: 3px; height: 60px;">
<span style="margin-left: 5px;">
<a href="RemoveUser.jsp?<%=username%>">Remove</a>
</span>
</td>