Definition and usage of public model classes of CI framework

<?php
/**
 * Created by PhpStorm.
 * User: kangjianrong
 * Date: 16-8-26
 * Time: 上午10:29
 */
class My_model extends CI_Model {
  //数据库
  public $errors = array();
  const dataBase = &#39;qndnew&#39;;
  public function __construct()
  {
    // Call the CI_Model constructor
    parent::__construct();
  }
  /**
   * 查询分页数据（使用于简单的单表操作）
   * @param string $model 模型     例如：User_model
   * @param string $table 表名
   * @param string $select_fields 要显示字段
   * @param array $param 查询条件：
   *   compare（比较）:
   *     array($key => $val) $key为要操作的字段，$val为要操作的值
   *     array(&#39;name !=&#39; => $name, &#39;id <&#39; => $id, &#39;date >&#39; => $date);
   *   like(模糊查询)
   *     array(&#39;title&#39; => $match, &#39;page1&#39; => $match, &#39;page2&#39; => $match)
   *   customStr（自定义字符串）:
   *     "name=&#39;Joe&#39; AND status=&#39;boss&#39; OR status=&#39;active&#39;"
   *   in:
   *     array(&#39;userName&#39; => array(&#39;Frank&#39;, &#39;Todd&#39;, &#39;James&#39;))
   * @param string $page 当前页数（查询全部数据时，设置为空）
   * @param string $limit 查询条数（查询全部数据时，设置为空）
   * @param array $order 排序条件：
   *   array($key => $val)
   *   $key为排序依据的字段，
   *   $val为排序的方式【asc (升序，默认)或 desc(降序), 或 random(随机)】
   * @$isReturnCount boole    是否返回总条数
   * @return array|boolean
   *
   */
  public function pageData($model, $table, $param = array(),$select_fields = &#39;&#39;, $page = &#39;1&#39;, $limit = &#39;15&#39;, $order = array(),$isReturnCount = true){
    if(empty($model) || empty($table)){
      return false;
    }
    $this -> load -> model($model);
    $table = $this->db->dbprefix.$table;
    //处理查询字段
    if(!empty($select_fields)){
      $this->db->select($select_fields)->from($table);
    }elseif(isset($this -> $model -> selectFields)){
      $this->db->select($this -> $model -> selectFields)->from($table);
    }else{
      $this->db->select(&#39;*&#39;)->from($table);
    }
    //处理查询条件
    if (is_array($param) && count($param) > 0){
      $this -> parseParam($param);
    }
    //统计总数
    if($isReturnCount){
      $rs[&#39;count&#39;]  = $this->db->count_all_results(&#39;&#39;,false);//不重置查询构造器
      array_push($this -> errors,$this->db->last_query());
    }
    //分页数据处理
    if(isset($page) && isset($param[&#39;limit&#39;])){
      //分页边界值 设置
      $offset = $param[&#39;page&#39;] <= 1 ? 0 : ($param[&#39;page&#39;]-1) * $param[&#39;limit&#39;];
      $this->db->limit($param[&#39;limit&#39;], $offset);
    }
    //排序规则的组合
    if (!empty($order) && is_array($order))
    {
      foreach ($order as $key => $val)
      {
        $this->db->order_by($key, $val);
      }
    }else{
      //默认按照此表的主键倒序
      $primary = $this->getPrimary();
      if(!empty($primary))
      {
        $this->db->order_by($primary, &#39;DESC&#39;);
      }
    }
    $query = $this->db->get();
    array_push($this -> errors,$this->db->last_query());
    $rs[&#39;list&#39;] = $query->result_array();
    return $rs;
  }
  /**
   * 解析参数
   */
  private function parseParam($param){
    if(isset($param[&#39;compare&#39;])){
      foreach ($param[&#39;compare&#39;] as $key => $val){
        if (!empty($val)) $this->db->where($key, $val);
      }
    }
    if(isset($param[&#39;like&#39;])){
      foreach ($param[&#39;like&#39;] as $key => $val){
        if (!empty($val)) $this->db->like($key, $val);
      }
    }
    if(isset($param[&#39;in&#39;])){
      foreach ($param[&#39;in&#39;] as $key => $val){
        if (!empty($val)) $this->db->where_in($key, $val);
      }
    }
    if(isset($param[&#39;customStr&#39;])){
      if (!empty($val)) $this->db->where($param[&#39;customStr&#39;]);
    }
  }
  /**
   * 新增信息
   * @param string $table 表名称
   * @param array $param 数据变量
   * @return INT ID
   */
  public function add($table = &#39;&#39;, $param = array())
  {
    if(empty($table) || !is_array($param) || empty ($param)){
      return FALSE;
    }
    //写入数据表
    $this->db->insert($table, $param);
      array_push($this -> errors,$this->db->last_query());
    //返回记录ID
    return $this->db->insert_id();
  }
  /**
   * 更新分类信息
   * @param string  $table   表名称
   * @param string  $primary  表主键
   * @param int    $id     分类ID
   * @param array   $param   更新的数据
   * @return type
   */
  public function update($table = &#39;&#39;, $primary = &#39;&#39;, $id = 0, $param = array())
  {
    if(empty($table) || empty($primary) || empty($param) || empty($id))
    {
      return FALSE;
    }
    $id = (int)$id;
    $this->db->where($primary, $id)
         ->limit(1)
         ->update($table, $param);
    array_push($this -> errors,$this->db->last_query());
    return $this->db->affected_rows();
  }
  /**
   * 删除指定ID记录
   * @param string  $table   表名称
   * @param string  $primary  表主键
   * @param array   $id     分类ID
   * @return int
   */
  public function delete($table = &#39;&#39;, $primary = &#39;&#39;, $id = array()){
    if(empty($table) || empty($primary) || empty($id)){
      return FALSE;
    }
    $this->db->where_in($primary, $id)
        ->delete($table);
    array_push($this -> errors,$this->db->last_query());
    return $this->db->affected_rows();
  }
  /**
   * 获取表的主键
   * @param string  $database  数据库名称
   * @param strting  $table   表名称
   */
  public function getPrimary($table = &#39;&#39;, $database = self::dataBase)
  {
    if(empty($database) || empty($table))
    {
      return FALSE;
    }
    $sql = "SELECT k.column_name
        FROM information_schema.table_constraints t
        JOIN information_schema.key_column_usage k
        USING (constraint_name,table_schema,table_name)
        WHERE t.constraint_type=&#39;PRIMARY KEY&#39;
         AND t.table_schema=&#39;qndnew&#39;
         AND t.table_name=&#39;qnd_user&#39;";
    $query = $this->db->query($sql)->result_array();
    return isset($query[0][&#39;column_name&#39;]) ? $query[0][&#39;column_name&#39;] : false;
  }
  /**
   * debug sql语句
   */
  public function debugSql(){
    if(count($this->errors) > 0){
      foreach($this->errors as $val){
        echo $val.&#39;<br>&#39;;
      }
    }
  }
}

class User_model extends My_model {
  const USER = 'qnd_user';
  public $selectFields = array(
    'id',
    'guid',
    'phone',
    'userName',
    'password',
    'headPortraits',
    'nickName',
    'createTime',
  );
  const SMS_ROLE = 'qnd_role';
  public function __construct()
  {
  }
}

public function modelTest(){
    $this -> load -> model('User_model'); // 載入 model
    $whereArr = array(
            'compare'=>array(
              'userName' => 'Frank',
            ),
          );
    $rs = $this -> User_model -> pageData('User_model','user',$whereArr);
    print_r($rs);
    $this -> User_model -> debugSql();
  }