JSP網站開發基礎總結《五》

2019-11-14 23:20:56

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jsp網站開發基礎總結《五》

　　開始本篇總結之前，首先聊一聊上一篇中存在的一點小問題，上上篇總結數據庫創建表時，存在一個問題，name、year、form好像屬于關鍵字，不能做為表的屬性，所以大家注意一下，在創建表時保證表的屬性不存在沖突，故而上一篇中關于sql語句的地方大家需要修改一下表的屬性名。

　　下面開始本篇關于JSP與MySQL的交互連接，為了方便總結，我將以創建一個學生信息管理系統為目標，本篇就以登錄功能的實現為主體進行總結。

　1、創建管理員表：

　2、創建一個管理員類：

public class Manager {    PRivate int id;    private String name ;     private String passWord;    private int key;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }    public int getKey() {        return key;    }    public void setKey(int key) {        this.key = key;    }    }

　3、添加用戶名、密碼判斷方法：

public class ManagerMaImp {    //登錄驗證    public boolean getByName(String name, String password){        System.out.println(name+"    "+password);        boolean flag = false;        Connection conn = null;        Statement st = null;        ResultSet rs = null;        conn = DBO.getConnection();        String sql = "select * from manager where user_name='"+name+"' and pwd='"+password+"' and num="+1;        try {            st = conn.createStatement();            rs = st.executeQuery(sql);            if(rs.next()){                flag = true;            }        } catch (SQLException e) {            e.printStackTrace();        }        return flag;    }}

　4、設計登錄JSP頁面：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><%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>學生管理系統登錄</title>        <meta http-equiv="pragma" content="no-cache">    <meta http-equiv="cache-control" content="no-cache">    <meta http-equiv="expires" content="0">        <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">    <meta http-equiv="descr　　效果圖：
　　
　5、用于身份判斷的select：
public class login extends HttpServlet {    public void doGet(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {        doPost(request, response);    }    public void doPost(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {        request.setCharacterEncoding("utf-8");        response.setCharacterEncoding("utf-8");        String name = request.getParameter("name");        String password = request.getParameter("pwd");        ManagerMaImp mmi = new ManagerMaImp();        boolean flag = mmi.getByName(name, password);        if(flag){            StudentMaImp smi = new StudentMaImp();            List<Student> list = new ArrayList<Student>();            list = smi.getAll();            request.setAttribute("list", list);            request.getRequestDispatcher("All.jsp").forward(request, response);        }else{            response.sendRedirect("Login.jsp");        }    }}
　6、主界面（All.jsp）：
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><%@page import="com.mysql.jsp.student.Student"%><%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>遍歷數據庫</title>        <meta http-equiv="pragma" content="no-cache">    <meta http-equiv="cache-control" 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">  </head>    <body>  <% List<Student> list = (List<Student>)request.getAttribute("list"); %>    <center>        <h1>遍歷數據庫中的數據</h1>        <hr/>        <form action="get" method="post">            <table width="80%">                <tr>                    <td><a href="Add.jsp">添加</a></td><td>&nbsp;</td><td>精確查找:<input type="text" name="queding"/></td><td>&nbsp;</td><td>模糊查找:<input type="text" name="mohu"/></td>                </tr>            </table>        </form>        <table border="1" width="80%">            <TR>                <TD>ID</TD><td>姓名</td><td>性別</td><td>年齡</td><td>家鄉</td><td>學校</td><td colspan="2">操作</td>            </TR>            <%                if(list.size()!=0){                    for(int i=0; i<list.size(); i++){                        Student student = list.get(i);            %>                    <tr><TD><%=student.getId() %></TD><td><%=student.getName() %></td><td><%if(student.getSex()==1){ %>男<%}else{ %>女<%} %></td><td><%=student.getYear() %></td><td><%=student.getFrom() %></td><td><%=student.getSchool() %></td><td><a href="getId?id=<%=student.getId() %>">修改</a></td><td><a href="del?id=<%=student.getId() %>">刪除</a></td></tr>            <%                    }                }             %>        </table>    </center>  </body></html>
　　效果圖：
　　
　　本篇總結：本篇提到了select，JSP就是通過select與后臺數據庫進行交互的，我們上一篇總結的增刪改查方法，將會在接下來的幾篇一一為大家實現具體的使用。在主界面JSP代碼中，你一定看到了很多:<%%>，我們可以在<%添加JAVA代碼%>。
　　下一篇將系統為大家總結增、刪、改的具體操作。