Javaweb简易程序的完善:

      今日完善了上周测试的web程序修改功能,做出了最终的修改功能,对于修改功能一直是我以前不太会的点,之前我会修改的函数的编写,但是不太明确在jsp文件中参数的传递,经常导致页面显示修改成功而数据库没有改变的显现,曾经一度想过将修改做成删除加增加,但是今天我在经过学习别人在修改的jsp文件中的操作,学会了修改的操作,完善了之前的测试程序。

修改部分代码

Test.java中修改部分代码:

 1 public void revisedata(String biao0,String zheng,String tian,String biao)
 2     {
 3         Connection connection = getConnection();
 4         PreparedStatement preparedStatement=null;
 5         try {
 6 
 7             String sql = "update bao set 标题=?,内容=?,坚持天数=? where 标题=?";
 8             preparedStatement=connection.prepareStatement(sql);
 9             preparedStatement.setString(1,biao);
10             preparedStatement.setString(2,zheng);
11             preparedStatement.setString(3,tian);
12             preparedStatement.setString(4,biao0);
13             preparedStatement.executeUpdate();
14 
15         } catch (SQLException  e) {
16             e.printStackTrace();
17         }finally{
18             close(preparedStatement);
19             close(connection);
20         }
21     }

jsp文件中修改部分:

revise.jsp

 1 <%@ page contentType="text/html;charset=UTF-8" language="java" %>
 2 <html>
 3 <head>
 4     <title>修改</title>
 5 </head>
 6 <body>
 7 <form action="revisejudge.jsp" method="get">
 8     <p style="text-align:center;color: black; font-family: 宋体; font-size: 20px">
 9         <br> 要修改的日记标题: <input type="text" name="biao" /> <br>
10         <br><input type="submit" value="确定" />
11         <br> <input type="button" value="返回菜单" onclick="location.href='index.jsp'" /> <br>
12     </p>
13 </form>
14 </body>
15 </html>

revisejudge.jsp

 1 <%@ page language="java" import="java.sql.*" contentType="text/html; charset=UTF-8"
 2          pageEncoding="UTF-8"%>
 3 <!DOCTYPE html>
 4 <html>
 5 <head>
 6     <meta charset="UTF-8">
 7 </head>
 8 <body>
 9 
10 <jsp:useBean id="util" class="test.Test" scope="page" />
11 <%
12     String biao=(String)request.getParameter("biao");
13     if(biao==""){
14         out.print("<script language='javaScript'> alert('输入为空'); window.history.back(-1); </script>");
15     }
16     else if(!util.isSame(biao))
17     {
18         out.print("<script language='javaScript'> alert('该信息不存在'); window.history.back(-1); </script>");
19     }
20     else{
21 %>
22 <table border="1"style="text-align:center;">
23     <tr>
24         <td align="center" width=6%>标题</td>
25         <td align="center" width=8%>正文</td>
26         <td align="center" width=10%>天数</td>
27         <td align="center" width=3%>修改</td>
28     </tr>
29     <%
30         Connection connection = util.getConnection();
31         PreparedStatement preparedStatement=null;
32         ResultSet rs=null;
33         try {
34             String sql = "select * from bao";
35             preparedStatement=connection.prepareStatement(sql);
36             rs=preparedStatement.executeQuery();
37             while(rs.next()){
38                 if(biao.equals(rs.getObject(1)))
39                 {
40     %>
41     <tr>
42         <td align="center"><%=rs.getObject(1) %></td>
43         <td align="center"><%=rs.getObject(2) %></td>
44         <td align="center"><%=rs.getObject(3) %></td>
45         <td align="center"><a style="color:blue" href='revisejudge1.jsp?biao0=<%=rs.getObject(1) %>' onclick="javascript:return del()">修改</a> </td>
46     </tr>
47 
48     <%
49                 }
50             }
51         } catch (SQLException  e) {
52             e.printStackTrace();
53         }finally{
54             util.close(rs);
55             util.close(preparedStatement);
56             util.close(connection);
57         }
58     %>
59 </table>
60 <%
61     }
62 %>
63 <%--
64 界面提示
65 --%>
66 <script>
67     function del(){
68         var r = confirm("确定修改这条吗?")
69         if (r == true) {
70             return true;
71         } else {
72             return false;
73         }
74     }
75 </script>
76 <p style="text-align:center;color: black; font-family: 宋体; font-size: 20px">
77     <br> <input type="button" value="返回菜单" onclick="location.href='index.jsp'" /> <br>
78 </p>
79 </body>
80 </html>

revisejudge1.jsp

 1 <%@ page language="java" import="java.sql.*" contentType="text/html; charset=UTF-8"
 2          pageEncoding="UTF-8"%>
 3 <!DOCTYPE html>
 4 <html>
 5 <head>
 6   <meta charset="UTF-8">
 7 </head>
 8 <body>
 9 <jsp:useBean id="util" class="test.Test" scope="page" />
10 <%
11   String biao0=(String)request.getParameter("biao0");
12   session.setAttribute("biao0",biao0);
13 %>
14 <table border="1"style="text-align:center;">
15   <tr>
16     <td align="center" width="8%">标题</td>
17     <td align="center" width=8%>正文</td>
18     <td align="center" width=10%>天数</td>
19 
20   </tr>
21   <%
22     Connection connection = util.getConnection();
23     PreparedStatement preparedStatement=null;
24     ResultSet rs=null;
25     try {
26       String sql = "select * from bao";
27       preparedStatement=connection.prepareStatement(sql);
28       rs=preparedStatement.executeQuery();
29       while(rs.next()){
30         if(biao0.equals(rs.getObject(1)))
31         {
32   %>
33   <tr>
34     <td align="center"><%=rs.getObject(1)%></td>
35     <td align="center"><%=rs.getObject(2) %></td>
36     <td align="center"><%=rs.getObject(3) %></td>
37   </tr>
38   <%
39         }
40       }
41     } catch (SQLException  e) {
42       e.printStackTrace();
43     }finally{
44       util.close(rs);
45       util.close(preparedStatement);
46       util.close(connection);
47     }
48   %>
49 </table>
50 
51 <form action="revisejudge2.jsp" method="get">
52       <br>
53       <br>
54       修改信息
55       <br>
56       <br>
57       标题:
58       <br>
59       <input type="text" name="biao">
60       <br>
61       <br>
62       正文:
63       <br>
64       <textarea  style="width: auto" name="zheng"></textarea>
65       <br>
66       天数:
67       <br>
68       <input type="text" name="tian">
69     <br><input type="submit" value="提交" />
70     <br>
71     <br> <input type="button" value="返回菜单" onclick="location.href='index.jsp'" /> <br>
72 </form>
73 </body>
74 </html>

revisejudge2.jsp

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2          pageEncoding="UTF-8"%>
 3 <!DOCTYPE html>
 4 <html>
 5 <head>
 6     <meta charset="UTF-8">
 7 </head>
 8 <body>
 9 <jsp:useBean id="util" class="test.Test" scope="page" />
10 <%
11     request.setCharacterEncoding("UTF-8");
12     String biao0=(String)session.getAttribute("biao0");
13     String biao=(String)request.getParameter("biao");
14     String zheng=(String)request.getParameter("zheng");
15     String tian=(String)request.getParameter("tian");
16 
17     if(biao==""||zheng==""||tian=="")
18     {
19         out.print("<script language='javaScript'> alert('输入为空');window.history.back(-1);</script>");
20     }
21     else
22     {
23         util.revisedata(biao0,zheng,tian,biao);
24         out.print("<script language='javaScript'> alert('修改成功');</script>");
25         response.setHeader("refresh", "0;url=search.jsp");
26     }
27 %>
28 <p style="text-align:center;color: black; font-family: 宋体; font-size: 20px">
29     <br> <input type="button" value="返回菜单" onclick="location.href='index.jsp'" /> <br>
30 </p>
31 </body>
32 </html>
02-28 22:07