本文实例讲述了Codeigniter的Setting增强配置类。分享给大家供大家参考，具体如下：

该增强配置类适用配置项要求比较灵活的项目。可实现预加载配置、组配置、单项调取、增、删、改配置，无需在改动config文档。

使用：

在需要的地方
复制代码 代码如下:$this->load->library('setting');
对于预加载项可以使用复制代码 代码如下:$this->config->item();进行获取
对于临时调取项可以使用复制代码 代码如下:$this->setting->item();进行获取

首先，创建数据表

CREATE TABLE `system_settings` ( `id` int(11) unsigned NOT NULL AUTO_INCREMENT, `key` varchar(64) NOT NULL DEFAULT '', `value` mediumtext NOT NULL, `group` varchar(55) NOT NULL DEFAULT 'site', `autoload` enum('no','yes') NOT NULL DEFAULT 'yes', PRIMARY KEY (`id`,`key`), KEY `name` (`key`), KEY `autoload` (`autoload`)) ENGINE=MyISAM AUTO_INCREMENT=11 DEFAULT CHARSET=utf8;

然后，在application/libraries目录下创建setting.php，内容如下

<?phpif (!defined('BASEPATH')) exit('No direct script access allowed');class Setting { private $_ci; private $settings_autoloaded; private $settings = array(); private $settings_group = array(); private $settings_db; public function __construct() { $this->_ci = &get_instance(); $this->settings_db = $this->_ci->config->item('settings_table'); $this->autoload(); } // ------------------------------------------------------------------------ // 华丽的分割线 正式开始 // ------------------------------------------------------------------------ /** * 从数据库获取所有自动加载的设置 */ public function autoload() { //如果存在则直接返回 if (!empty($this->settings)) { return $this->settings; } //如果系统不存在数据表则返回false if (!$this->_ci->db->table_exists($this->settings_db)) { return FALSE; } //查询标记为自动加载的项 $this->_ci->db->select('key,value')->from($this->settings_db)->where('autoload', 'yes'); $query = $this->_ci->db->get(); if ($query->num_rows() == 0) { return FALSE; } //循环写入系统配置 foreach ($query->result() as $k => $row) { $this->settings[$row->key] = $row->value; $this->_ci->config->set_item($row->key, $row->value); } //标记会话，避免重复读库 //$this->_ci->session->set_userdata('settings_autoloaded', TRUE); return $this->settings; } // ------------------------------------------------------------------------ /** * 获取单个设定 * * <code> * <?php $this->settings->get('config_item'); ?> * </code> */ public function item($key) { if (!$key) { return FALSE; } //首先检查是否系统已经自动加载 if (isset($this->settings[$key])) { return $this->settings[$key]; } //查询数据库 $this->_ci->db->select('value')->from($this->settings_db)->where('key', $key); $query = $this->_ci->db->get(); if ($query->num_rows() > 0) { $row = $query->row(); $this->settings[$key] = $row->value; return $row->value; } // 查询不到结果则查找系统config，返回值或者false return $this->_ci->config->item($key); } // ------------------------------------------------------------------------ /** * 获取组配置 */ public function group($group = '') { if (!$group) { return FALSE; } $this->_ci->db->select('key,value')->from($this->settings_db)->where('group', $group); $query = $this->_ci->db->get(); if ($query->num_rows() == 0) { return FALSE; } foreach ($query->result() as $k => $row) { $this->settings[$row->key] = $row->value; $arr[$row->key] = $row->value; } return $arr; } // ------------------------------------------------------------------------ /** * 更改设置 */ public function edit($key, $value) { $this->_ci->db->where('key', $key); $this->_ci->db->update($this->settings_db, array('value' => $value)); if ($this->_ci->db->affected_rows() == 0) { return FALSE; } return TRUE; } // ------------------------------------------------------------------------ /** * 新增设置 */ public function insert($key, $value = '', $group = 'addon', $autoload = 'no') { // 检查是否已经被添加的设置 $this->_ci->db->select('value')->from($this->settings_db)->where('key', $key); $query = $this->_ci->db->get(); if ($query->num_rows() > 0) { return $this->edit($key, $value); } $data = array('key' => $key, 'value' => $value, 'group' => $group, 'autoload' => $autoload, ); $this->_ci->db->insert($this->settings_db, $data); if ($this->_ci->db->affected_rows() == 0) { return FALSE; } return TRUE; } // ------------------------------------------------------------------------ /** * 删除设置 */ public function delete($key) { $this->_ci->db->delete($this->settings_db, array('key' => $key)); if ($this->_ci->db->affected_rows() == 0) { return FALSE; } return TRUE; } // ------------------------------------------------------------------------ /** * 删除设置组及成员配置 */ public function delete_group($group) { $this->_ci->db->delete($this->settings_db, array('group' => $group)); if ($this->_ci->db->affected_rows() == 0) { return FALSE; } return TRUE; }}

最后，打开application/config/config.php，新增

/** * 系统配置表名 */$config['settings_table'] = "system_settings";

希望本文所述对大家基于Codeigniter框架的PHP程序设计有所帮助。