javaweb简单的增删改查之“通过姓名查找，查询所有信息”

Posted 2021-03-22 亮哥哥哥

1.方法
/*
     * 查看全部信息
     */
    public List<Member> selectByName(String name) {
        // TODO Auto-generated method stub
        List<Member> list=new ArrayList<Member>();
        PreparedStatement pre=null;
        ResultSet rs=null;
        try {
            String sql="select*from blog where name=?";
            pre=con.prepareStatement(sql);
            pre.setString(1, name);
            rs=pre.executeQuery();
            while(rs.next()) {
                Member user=new Member();
                user.setName(rs.getString("name"));
                user.setAge(rs.getString("age"));
                list.add(user);
            }
            
        }catch(SQLException e) {
            e.printStackTrace();
        }finally {
            Databass.Databass.close(rs, pre, con);
        }
        return list;
    }
    
    public List<Member> selectall(){
        List<Member> list=new ArrayList<Member>();
        try {
            String sql="select * from blog";
            PreparedStatement  pre=con.prepareStatement(sql);
            ResultSet rs=pre.executeQuery();
            while(rs.next()) {
                Member user=new Member();
                user.setName(rs.getString("name"));
                user.setAge(rs.getString("age"));
                list.add(user);
            }
            rs.close();
            pre.close();
            con.close();
            }catch(SQLException e) {
                e.printStackTrace();
            }
        return list;
    }

通过姓名查找servlet
/**
 * Servlet implementation class ServletSearchByname
 */
@WebServlet("/ServletSearchByname")
public class ServletSearchByname extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ServletSearchByname() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        response.getWriter().append("Served at: ").append(request.getContextPath());
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        //设置请求字体
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");
        String name=request.getParameter("name");
        Method ww=new Method();
        List<Member> list=ww.selectByName(name);
        request.setAttribute("list", list);
        request.getRequestDispatcher("/searchByName1.jsp").forward(request, response);
        
    }

}

查询所有信息servlet
package Servlet;

import java.io.IOException;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import Member.Member;
import Method.Method;


/**
 * Servlet implementation class ServletShow
 */
@WebServlet("/ServletShow")
public class ServletShow extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ServletShow() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        response.getWriter().append("Served at: ").append(request.getContextPath());
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //设置请求字体
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");
        Method sd=new Method();
        List<Member> list=sd.selectByName(request.getParameter("name"));
        request.setAttribute("list", list);
        request.getRequestDispatcher("/show.jsp").forward(request, response);
    }

}

输入姓名进行查找
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ page import="Method.*,Member.*,Servlet.*,java.util.List" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>通过姓名进行查找</title>
</head>
<body>
<form action="ServletSearchByname" method="post">
请输入要查询的姓名：
<a><input type="text" name="name"></a>
<a><input type="submit" value="查询"></a>
</form>



</body>
</html>

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@page import="Member.*,Method.*,java.util.List,Servlet.*" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>通过姓名查找</title>
</head>
<body>

<table>
<tr>
            <td>姓名</td>
            <td>年龄</td>
            </tr>
<%
String name=request.getParameter("name");
Method ww=new Method();
List<Member> list=ww.selectByName(name);
request.setAttribute("list", list);
%>
<c:forEach var="u" items="${list}">
                  <tr>
                    
                    <td>${u.name}</td>
                    <td>${u.age }</td>
                    
                </tr>
                </c:forEach>
</table>



</body>
</html>

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
    <%@page import="Member.*,Method.*,java.util.List,Servlet.*" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<table border="" >
            <tr>
            <td>姓名：</td>
            <td>年龄：</td>
            </tr>
            
            <%
                    
                    Method sd=new Method();
                    List<Member> list=sd.selectall();
                    request.setAttribute("list", list); %>
            
                  <c:forEach var="u" items="${list}">
                  <tr>
                    
                    <td>${u.name}</td>
                    <td>${u.age }</td>
                    
                </tr>
                  
                 
                  </c:forEach>
            </table>
            <a href="main.jsp">返回主页</a>
            


</body>
</html>