CI(Codeigniter)的Setting增强配置类实例

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

_ci = &get_instance();
    $this->settings_db = $this->_ci->config->item('settings_table');
    $this->autoload();
  }
  // ------------------------------------------------------------------------
  // 华丽的分割线 正式开始
  // ------------------------------------------------------------------------
  
  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;
  }
  // ------------------------------------------------------------------------
  
  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);
  }
  // ------------------------------------------------------------------------
  
  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;
  }
  // ------------------------------------------------------------------------
  
  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;
  }
  // ------------------------------------------------------------------------
  
  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;
  }
  // ------------------------------------------------------------------------
  
  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;
  }
  // ------------------------------------------------------------------------
  
  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

$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。