简单实现网页信息分页显示
<%!
int toptalPageCount=0; //信息总页数
int pageSize = 5; //页面大小，即每页显示的记录数
int totalCount; //信息的总条数
int index=0;
Connection con = null;
PreparedStatement ps=null;
ResultSet rs =null;
//给toptalPageCount赋值，算出一共多少页
void setTotalCount(int totalCount){
toptalPageCount = this.totalCount%pageSize ==0?(this.totalCount/pageSize):(this.totalCount/pageSize+1);
}
%>
<%
//传递页码跳转的值
if(request.getParameter("index") != null){
index =Integer.parseInt(request.getParameter("index"));
}
//连接数据库
Context ctx = new InitialContext();
DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/news");
try{
//查询一共多少条信息
con = ds.getConnection();
ps = con.prepareStatement("select count(1) from news");
rs = ps.executeQuery();
//给totalCount赋值
if(rs.next()){
totalCount =Integer.parseInt(rs.getString("count(1)"));
}
//判断上一页，下一页
if(index <=0){
index =1;
}else if(index >=12){
index =12;
}
//执行分页查询
ps = con.prepareStatement("select ntitle from news limit ?,?");
ps.setInt(1, (index-1)*pageSize);
ps.setInt(2, pageSize);
rs = ps.executeQuery();
//读取新闻数据
while(rs.next()){
out.print(rs.getString("ntitle")+"<br>");
}
//传递totalCount参数
setTotalCount(totalCount);
out.print("<a href='index.jsp?index="+(index-1)+"'>"+"上一页"+"</a>");
//显示页码
for(int i=0; i<toptalPageCount;i++){
out.print("<a href='index.jsp?index="+(i+1)+"'>"+(i+1)+"</a> ");
}
out.print("<a href='index.jsp?index="+(index+1)+"'>"+"下一页"+"</a>");
}catch(Exception e){
e.printStackTrace();
}finally{
//释放资源
try{
rs.close();
}catch(Exception e){
e.printStackTrace();
}
try{
ps.close();
}catch(Exception e){
e.printStackTrace();
}
try{
con.close();
}catch(Exception e){
e.printStackTrace();
}
}
%>
