Struts2(九.初始化用户列表时显示用户照片数目)
1.userlist.jsp
//显示每个用户照片的数目(遍历每个用户)
$(".picture").each(function(i,e){
$.post("${pageContext.request.contextPath}/picture/getpicnum",{"picture.uid":e.lang},function(data){
e.innerHTML=e.innerHTML+"("+ data +")"
});
});
2.PictureAction
/** * 通过当前用户id(uid)获取在数据库中照片的张数 * @return * @throws ClassNotFoundException * @throws SQLException * @throws NamingException * @throws IOException */ public String getpicnum() throws ClassNotFoundException, SQLException, NamingException, IOException{ PictureDAO dao=new PictureDAO(); int num=dao.getPictureNum(picture.getUid()); out=response.getWriter(); out.print(num); return null; }
3.PictureDAO
/** * 通过uid(当前用户id)从数据库获得当前用户的所有照片的张数 * @param id * @return * @throws SQLException * @throws NamingException */ public int getPictureNum(int id) throws SQLException, NamingException{ if(conn.isClosed()) { Context ctx = new InitialContext(); DataSource ds = (DataSource) ctx.lookup("java:comp/env/jdbc/mysql"); conn = ds.getConnection(); } int num = 0; sql="select count(*) from pictures where uid = ?"; ps=conn.prepareStatement(sql); ps.setInt(1, id); ResultSet rs = ps.executeQuery(); while(rs.next()){ num=rs.getInt(1); } conn.close(); return num; }
4.效果