载入样式以最后载入的定位为准(后写的样式优先级高,前数岁提是大家的权重一样)
1、!important权值最高。
2、弊毕轿内联样式表的权值为 1000。
3、ID 选择器的权值为 100。
4、Class 类选择器的权值为 10。
5、HTML 标签(类型)选择器的权值为 1。
你的传值方法用反了,你上面的<form>表单里面写的方法是post但是你在后台Servlet处理的时候用的是doGet方法处理,是不可能接受到数据的。做这个上传东西的话,需要导入物信团一些外包,像cosFir这种包来实现比较好一点。如果只是实现提交功能的话,首先思路要明确,你表单的内容提交过来,要直接获取的话用你的方法就可以了,但是注意传值的方法,一般用post传值,因为get方法传值太小,容易丢失数据。还有就是你传过来了在servlet处理的时候最后弄个标记来处理,这样可以利用if分支来处理多个页面出来的的请求,当然servlet也只是初步的处理,你最后还得调用javabean来处理,就是你要用一个业务类来专门处理你的sql语句接串,然后提交数据可处理。看一下我写的一个登录的小程序:
登录页面:index.jsp
<%@ page language="坦返java" import="java.util.*" pageEncoding="GBK"%>
<%
String path = request.getContextPath()
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control"罩橘 content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<%
request.setCharacterEncoding("gbk")
String rs_flag=(String)request.getAttribute("rs_flag")
if(rs_flag!=null){
out.println(rs_flag)
}
%>
请登陆:
<form action="LoginServlet" name="form1" method="post">
用户名:<input type="text" name="consumername" >
密码:<input type="password" name="consumerpsw">
<input type="submit" name="sub" value="登陆">
</form>
</body>
</html>
servlet处理Loginservlet
package com.icss.contr
import java.io.IOException
import java.sql.SQLException
import javax.servlet.ServletException
import javax.servlet.http.HttpServlet
import javax.servlet.http.HttpServletRequest
import javax.servlet.http.HttpServletResponse
import com.icss.dao.UserDao
public class LoginServlet extends HttpServlet {
/**
* Constructor of the object.
*/
public LoginServlet() {
super()
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy()// Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response)
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
/*
* servlet要完成用户提交信息的整理
*
*/
request.setCharacterEncoding("GBK")
String consumername=request.getParameter("consumername")
String consumerpsw=request.getParameter("consumerpsw")
int flag=0
/*
* servlet要控制请求由那个业务类处理
*/
UserDao userdao=new UserDao()
try {
flag=userdao.validate(consumername, consumerpsw)
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace()
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace()
}
/*
* servlet 要根据业务类处理的结果(判断分支)选择响应的jsp页面
*/
if(flag==0){
/*
* 在响应之前在做显示信息的准备
*/
String rs_flag="登陆失败!请重试!"
request.setAttribute("rs_flag",rs_flag)
//转发
request.getRequestDispatcher("index.jsp").forward(request,response)
}else{
request.getRequestDispatcher("main.jsp").forward(request,response)
}
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
然后调用javabean业务处理类Userdao来处理
package com.icss.dao
import java.sql.ResultSet
import java.sql.SQLException
import java.util.ArrayList
import java.util.HashMap
import java.util.List
import java.util.Map
import com.icss.base.DbCon
import com.icss.vo.UserVo
public class UserDao extends DbCon {
public int validate(String consumername,String consumerpsw) throws ClassNotFoundException, SQLException{
getCon()
String sql="select * from consumer where consumername='"+consumername+"' and consumerpsw='"+consumerpsw+"'"
int flag=0
ResultSet rs=DbCon.st.executeQuery(sql)
if(rs.next()){
flag=1
}
rs.close()
closeCon()
return flag
}
}
处理完数据库的接串以及查询以后返回结果到servlet做处理,然后返回jsp页面就可以了。
下面这个是连接数据库的,我不知道你用什么数据库,我用的是oracle,不过都差不多,你看一下把:
package com.icss.base
import java.sql.Connection
import java.sql.DriverManager
import java.sql.SQLException
import java.sql.Statement
public class DbCon {
public static Connection conn=null
public static Statement st=null
public void getCon() throws ClassNotFoundException, SQLException{
Class.forName("oracle.jdbc.driver.OracleDriver")//创建数据库驱动对象
conn=DriverManager.getConnection("jdbc:oracle:thin:@192.168.0.207:1521:ICSS","TEST","MANAGER")//创建数据库连接对象
st=conn.createStatement()//创建执行sql语句对象
}
public void closeCon() throws SQLException{
if(st!=null){
st.close()
}
if(conn!=null){
conn.close()
}
}
/**
* @param args
*/
public static void main(String[] args) {
DbCon dbc=new DbCon()
try {
dbc.getCon()
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace()
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace()
}
}
}
呼呼,写这个真是有点浪费时间~·不过好歹完工了,当作是复习一下。希望对你有用。。
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