php分页类，附带例子

<?php /** * The Database class work tighly with a MySQL database. * The class methods interact with the MySQL database and returns resultsets or values from the MySQL database. * The class should be used as a replacement for handling MySQL calls flat out in the open PHP code. **/ class Database { private $_queries, $_result, $_server, $_user, $_password, $_database; public function __construct($database, $server, $user, $password) { $this->_queries = 0; $this->_result = null; $this->_server = $server; $this->_user = $user; $this->_password = $password; $this->_database = $database; $this->connect(); $this->execQuery("SET NAMES 'utf8'"); } private function connect() { mysql_connect($this->_server, $this->_user, $this->_password) or trigger_error('Server connection failed.', FATAL); mysql_select_db($this->_database) or trigger_error('Database connection failed.', FATAL); } public function setDatabase($database) { $this->_database = $database; $this->connect(); } public function execQuery($query) { $this->_queries++; $this->_result = mysql_query($query); if(!$this->_result) { trigger_error('Method [' . __FUNCTION__ . "] failed [Q: $query]", WARNING); } return $this->_result; } public function fetchValue($query) { $result = $this->execQuery("$query LIMIT 1"); $tuples = mysql_fetch_row($result); return $tuples[0]; } public function fetchDouble($query) { $result[0] = $this->execQuery($query); $result[1] = mysql_num_rows($result[0]); return $result; } public function fetchObject($result = null) { $result = $result == null ? $this->_result : $result; if ($result == null || mysql_num_rows($result) < 1) { return null; } else { return mysql_fetch_object($result); } } public function fetchArray($result = null) { $result = $result == null ? $this->_result : $result; if ($result == null || mysql_num_rows($result) < 1) { return null; } else { return mysql_fetch_array($result,MYSQL_ASSOC); } } public function fetchNum($result = null) { if ($result != null) { return mysql_num_rows($result); } else if ($this->_result != null) { return mysql_num_rows($this->_result); } else { trigger_error('Method [' . __FUNCTION__ . '] failed [R: No resultset available]', WARNING); } } public function dataSeek($result, $seek) { return mysql_data_seek($result, $seek); } public function close() { mysql_close(); } } ?>