两个jsp文件:
1.login.jsp
<%@ page contentType="text/html; charset=GBK" %><html>
<head>
<title>
login
</title>
</head>
<body bgcolor="#ffffff">
<h1>
<!-- 输出的内容 -->
Welcome to login!
</h1>
<form action="checklogin.jsp" method="POST">
<!-- 构造输入域和按钮 -->
username:<input name="username" value="kingbill">
password:<input name="password" value="111111">
<input type="submit" value="确认"/>
<input type="reset"/>
</form>
</body>
</html>2.checklogin.jsp
<%@ page contentType="text/html; charset=GBK" %>
<%@page import="java.sql.*"%>
<%
//获取表单输入参数
String username = request.getParameter("username");
String password = request.getParameter("password");boolean loginsuccess = false;
Connection con = null;
Statement stmt = null;
ResultSet rs = null;System.out.println(username + "89799 " + password);
try {
Class.forName("org.gjt.mm.mysql.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/login",
"root","123456789");
stmt = con.createStatement();
String sql ="select * from user where username = '" + username + "'";System.out.println(username + "99999 " + password);
rs = stmt.executeQuery(sql);System.out.println(username + "8798979 " + password);
System.out.println(rs.getInt("userId") + " " +
rs.getString("username") + " " +
rs.getString("password"));
System.out.println(username + " " + password);
while (rs.next()){
System.out.println(rs.getInt("userId") + " " +
rs.getString("username") + " " +
rs.getString("password"));
if(password.equals(rs.getString("password"))){
loginsuccess = true;
}
}
} catch (Exception sqlex1) {
sqlex1.printStackTrace();
} finally {
if (con != null) {
try {
con.close();
} catch (Exception sqlex2) {
sqlex2.printStackTrace();
}
}
}
if(loginsuccess){
%>
<jsp:forward page = "welcome.jsp"></jsp:forward>
<%
}else{
%>
<!-- (2) -->
<jsp:forward page="error.jsp"></jsp:forward>
<%
}
%>请教,红色部分的打印信息为什么是NULL,好象接收或者发送表单上出了问题。新人,还请大家多指教,谢谢!
1.login.jsp
<%@ page contentType="text/html; charset=GBK" %><html>
<head>
<title>
login
</title>
</head>
<body bgcolor="#ffffff">
<h1>
<!-- 输出的内容 -->
Welcome to login!
</h1>
<form action="checklogin.jsp" method="POST">
<!-- 构造输入域和按钮 -->
username:<input name="username" value="kingbill">
password:<input name="password" value="111111">
<input type="submit" value="确认"/>
<input type="reset"/>
</form>
</body>
</html>2.checklogin.jsp
<%@ page contentType="text/html; charset=GBK" %>
<%@page import="java.sql.*"%>
<%
//获取表单输入参数
String username = request.getParameter("username");
String password = request.getParameter("password");boolean loginsuccess = false;
Connection con = null;
Statement stmt = null;
ResultSet rs = null;System.out.println(username + "89799 " + password);
try {
Class.forName("org.gjt.mm.mysql.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/login",
"root","123456789");
stmt = con.createStatement();
String sql ="select * from user where username = '" + username + "'";System.out.println(username + "99999 " + password);
rs = stmt.executeQuery(sql);System.out.println(username + "8798979 " + password);
System.out.println(rs.getInt("userId") + " " +
rs.getString("username") + " " +
rs.getString("password"));
System.out.println(username + " " + password);
while (rs.next()){
System.out.println(rs.getInt("userId") + " " +
rs.getString("username") + " " +
rs.getString("password"));
if(password.equals(rs.getString("password"))){
loginsuccess = true;
}
}
} catch (Exception sqlex1) {
sqlex1.printStackTrace();
} finally {
if (con != null) {
try {
con.close();
} catch (Exception sqlex2) {
sqlex2.printStackTrace();
}
}
}
if(loginsuccess){
%>
<jsp:forward page = "welcome.jsp"></jsp:forward>
<%
}else{
%>
<!-- (2) -->
<jsp:forward page="error.jsp"></jsp:forward>
<%
}
%>请教,红色部分的打印信息为什么是NULL,好象接收或者发送表单上出了问题。新人,还请大家多指教,谢谢!
解决方案 »
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