说明:用JSP+MySQL数据库创建留言本,首先要创建MySQL数据库,关于MySQL的使用请到 http://pinghui.51.net/download/012mysql.chm 下载教程。现在为了说明的需要,我们假设数据库已经建立完成,数据库的名称是pinghui,其中有comment表是记录留言信息的。
数据库的结构为:
+-----------+-------------+------+-----+---------------------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------+-------------+------+-----+---------------------+----------------+
| userid | int(11) | | PRI | 0 | auto_increment |
| username | char(20) | | | | |
| sex | char(2) | | | | |
| address | char(40) | YES | | NULL | |
| ip | char(15) | | | | |
| post | int(11) | YES | | 0 | |
| oicq | int(11) | YES | | 0 | |
| icq | int(11) | YES | | 0 | |
| telnumber | char(30) | YES | | NULL | |
| comment | text | | | NULL | |
| time | datetime | | | 0000-00-00 00:00:00 | |
+-----------+-------------+------+-----+---------------------+----------------+
如果你认为建立数据库太麻烦的话
建立数据库的语句为:
DROP DATABASE IF EXISTS pinghui;
CREATE DATABASE pinghui;
USE pinghui;
CREATE TABLE comment(
userid int NOT NULL DEFAULT 0 AUTO_INCREMENT PRIMARY KEY,
username char(20) NOT NULL,
sex char(2),
address char(40),
ip char(15) NOT NULL,
post int DEFAULT 0,
oicq int DEFAULT 0,
icq int DEFAULT 0,
telnumber char(30),
comment text NOT NULL,
time datetime NOT NULL
);
INSERT INTO comment (username,ip,comment,time) VALUES ("pinghui","127.0.0.1",
try{Page=Integer.parseInt(string_page);
}catch(NumberFormatException e)
{Page=0;
}
java.sql.Connection sqlConn; //数据库连接对象
java.sql.Statement sqlStmt; //语句对象
java.sql.ResultSet sqlRst; //结果集对象
//登记JDBC驱动对象
Class.forName ("org.gjt.mm.mysql.Driver").newInstance ();
//连接数据库
sqlConn= java.sql.DriverManager.getConnection ("jdbc:mysql://localhost/p","test","");
//创建语句对象
sqlStmt=sqlConn.createStatement
(java.sql.ResultSet.TYPE_SCROLL_INSENSITIVE,java.sql.ResultSet.CONCUR_READ_ONLY);
//执行Sql语句
String sqlQuery="select count(*) from comment";
sqlRst=sqlStmt.executeQuery (sqlQuery);
sqlRst.next();
int count=sqlRst.getInt(1); //取得总的留言记录数
if (Page>=0)RecoderPage=Page;//处理页面
else RecoderPage=0-Page*10;
if (RecoderPage>count/15){ RecoderPage=count/15; Page=RecoderPage; }//页面越界
RecoderRow=RecoderPage*15; //取得要显示的留言记录号
sqlQuery="select * from comment order by userid desc limit "+RecoderRow+",15;"; //一次读取15条记录
sqlRst=sqlStmt.executeQuery (sqlQuery);
%> 总共有条留言
{ //取得下一条记录 %> 第条
昵称: | 性别: | 地址: | |
电话: | 邮编: | OICQ: | ICQ: |
Email: " title="写信给留言者"> | 网址: " title="写信给留言者"> | ||
留言: - (来自) |
//下面对留言进行分页
int i=count/15; //总页,每页显示15条记录
int j=i/10; //总的大页 ,没10个页面分一大页
//Page 显示的页面
int StartPage;
//int HrefPage;
if (Page StartPage=Page/10; //10页分一次
out.print ("[共有"+(i+1)+"页]");
//out.print ("共有"+j+"屏");
//out.print ("显示第"+Page+"页");
//out.print ("StartPage="+StartPage);
if (StartPage>0)
out.print ("|前10页");
for (int k=0;k { int p=StartPage*10+k;
if (p>i) break;
if (p==Page)
out.print ("|第"+Integer.toString(p+1)+"页");
else
out.print ("|第"+Integer.toString(p+1)+"页");
}
if (StartPage
out.print ("|");
%>

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