PHP MongoDB数据库操作类代码

分享一个PHP实现的数据库操作类，参考mysql版的操作类实现的。
完整代码：

class HMongodb {
    private $mongo; //Mongodb连接
    private $curr_db_name;
    private $curr_table_name;
    private $error;
    public function getInstance($mongo_server, $flag=array())
    {
        static $mongodb_arr;
        if (empty($flag['tag']))
        {
            $flag['tag'] = 'default'; }
        if (isset($flag['force']) && $flag['force'] == true)
        {
            $mongo = new HMongodb($mongo_server);
            if (empty($mongodb_arr[$flag['tag']]))
            {
                $mongodb_arr[$flag['tag']] = $mongo;
            }
            return $mongo;
        }
        else if (isset($mongodb_arr[$flag['tag']]) && is_resource($mongodb_arr[$flag['tag']]))
        {
            return $mongodb_arr[$flag['tag']];
        }
        else
        {
            $mongo = new HMongodb($mongo_server);
            $mongodb_arr[$flag['tag']] = $mongo;
            return $mongo;
        }
    }
    /**
     * 构造函数
     * 支持传入多个mongo_server(1.一个出问题时连接其它的server 2.自动将查询均匀分发到不同server)
     *
     * 参数：
     * $mongo_server:数组或字符串-array("127.0.0.1:1111", "127.0.0.1:2222")-"127.0.0.1:1111"
     * $connect:初始化mongo对象时是否连接，默认连接
     * $auto_balance:是否自动做负载均衡，默认是
     *
     * 返回值：
     * 成功：mongo object
     * 失败：false
     */
    private function __construct($mongo_server, $connect=true, $auto_balance=true)
    {
     if (is_array($mongo_server))
     {
      $mongo_server_num = count($mongo_server);
      if ($mongo_server_num > 1 && $auto_balance)
      {
       $prior_server_num = rand(1, $mongo_server_num);
       $rand_keys = array_rand($mongo_server,$mongo_server_num);
       $mongo_server_str = $mongo_server[$prior_server_num-1];
       foreach ($rand_keys as $key)
       {
        if ($key != $prior_server_num - 1)
        {
         $mongo_server_str .= ',' . $mongo_server[$key];
        }
       }
      }
      else
      {
       $mongo_server_str = implode(',', $mongo_server);
      } }
      else
      {
       $mongo_server_str = $mongo_server;
      }
      try {
       $this->mongo = new Mongo($mongo_server, array('connect'=>$connect));
      }
      catch (MongoConnectionException $e)
      {
       $this->error = $e->getMessage();
       return false;
      }
    }
    /**
    * 连接mongodb server
    *
    * 参数：无
    *
    * 返回值：
    * 成功：true
    * 失败：false
    */
    public function connect()
    {
        try {
            $this->mongo->connect();
            return true;
        }
        catch (MongoConnectionException $e)
        {
            $this->error = $e->getMessage();
            return false;
        }
    }
    /**
    * select db
    *
    * 参数：$dbname
    *
    * 返回值：无
    */
    public function selectDb($dbname)
    {
        $this->curr_db_name = $dbname;
    }
    /**
    * 创建索引：如索引已存在，则返回。
    *
    * 参数：
    * $table_name:表名
    * $index:索引-array("id"=>1)-在id字段建立升序索引
    * $index_param:其它条件-是否唯一索引等
    *
    * 返回值：
    * 成功：true
    * 失败：false
    */
    public function ensureIndex($table_name, $index, $index_param=array())
    {
        $dbname = $this->curr_db_name;
        $index_param['safe'] = 1;
        try {
            $this->mongo->$dbname->$table_name->ensureIndex($index, $index_param);
            return true;
        }
        catch (MongoCursorException $e)
        {
            $this->error = $e->getMessage();
            return false;
        }
    }
    /**
    * 插入记录
    *
    * 参数：
    * $table_name:表名
    * $record:记录
    *
    * 返回值：
    * 成功：true
    * 失败：false
    */
    public function insert($table_name, $record)
    {
        $dbname = $this->curr_db_name;
        try {
            $this->mongo->$dbname->$table_name->insert($record, array('safe'=>true));
            return true;
        }
        catch (MongoCursorException $e)
        {
            $this->error = $e->getMessage();
            return false;
        }
    }
    /**
    * 查询表的记录数
    *
    * 参数：
    * $table_name:表名
    *
    * 返回值：表的记录数
    */
    public function count($table_name)
    {
        $dbname = $this->curr_db_name;
        return $this->mongo->$dbname->$table_name->count();
    }
    /**
    * 更新记录
    *
    * 参数：
    * $table_name:表名
    * $condition:更新条件
    * $newdata:新的数据记录
    * $options:更新选择-upsert/multiple
    *
    * 返回值：
    * 成功：true
    * 失败：false
    */
    public function update($table_name, $condition, $newdata, $options=array())
    {
        $dbname = $this->curr_db_name;
        $options['safe'] = 1;
        if (!isset($options['multiple']))
        {
            $options['multiple'] = 0; }
        try {
            $this->mongo->$dbname->$table_name->update($condition, $newdata, $options);
            return true;
        }
        catch (MongoCursorException $e)
        {
            $this->error = $e->getMessage();
            return false;
        }
    }
    /**
    * 删除记录
    *
    * 参数：
    * $table_name:表名
    * $condition:删除条件
    * $options:删除选择-justOne
    *
    * 返回值：
    * 成功：true
    * 失败：false
    */
    public function remove($table_name, $condition, $options=array())
    {
        $dbname = $this->curr_db_name;
        $options['safe'] = 1;
        try {
            $this->mongo->$dbname->$table_name->remove($condition, $options);
            return true;
        }
        catch (MongoCursorException $e)
        {
            $this->error = $e->getMessage();
            return false;
    } }
    /**
    * 查找记录
    *
    * 参数：
    * $table_name:表名
    * $query_condition:字段查找条件
    * $result_condition:查询结果限制条件-limit/sort等
    * $fields:获取字段
    *
    * 返回值：
    * 成功：记录集
    * 失败：false
    */
    public function find($table_name, $query_condition, $result_condition=array(), $fields=array())
    {
        $dbname = $this->curr_db_name;
        $cursor = $this->mongo->$dbname->$table_name->find($query_condition, $fields);
        if (!empty($result_condition['start']))
        {
            $cursor->skip($result_condition['start']);
        } www.jbxue.com
        if (!empty($result_condition['limit']))
        {
            $cursor->limit($result_condition['limit']);
        }
        if (!empty($result_condition['sort']))
        {
            $cursor->sort($result_condition['sort']);
        }
        $result = array();
        try {
            while ($cursor->hasNext())
            {
                $result[] = $cursor->getNext();
            }
        }
        catch (MongoConnectionException $e)
        {
            $this->error = $e->getMessage();
            return false;
        } www.jbxue.com
        catch (MongoCursorTimeoutException $e)
        {
            $this->error = $e->getMessage();
            return false;
        }
        return $result;
    }
    /**
    * 查找一条记录
    *
    * 参数：
    * $table_name:表名
    * $condition:查找条件
    * $fields:获取字段
    *
    * 返回值：
    * 成功：一条记录
    * 失败：false
    */
    public function findOne($table_name, $condition, $fields=array())
    {
        $dbname = $this->curr_db_name;
        return $this->mongo->$dbname->$table_name->findOne($condition, $fields);
    }
    /**
    * 获取当前错误信息
    *
    * 参数：无
    *
    * 返回值：当前错误信息
    */
    public function getError()
    {
        return $this->error;
    }
    /*** Mongodb类** examples:
     * $mongo = new HMongodb("127.0.0.1:11223");
    * $mongo->selectDb("test_db");
    * 创建索引
    * $mongo->ensureIndex("test_table", array("id"=>1), array('unique'=>true));
    * 获取表的记录
    * $mongo->count("test_table");
    * 插入记录
    * $mongo->insert("test_table", array("id"=>2, "title"=>"asdqw"));
    * 更新记录
    * $mongo->update("test_table", array("id"=>1),array("id"=>1,"title"=>"bbb"));
    * 更新记录-存在时更新，不存在时添加-相当于set
    * $mongo->update("test_table", array("id"=>1),array("id"=>1,"title"=>"bbb"),array("upsert"=>1));
    * 查找记录
    * $mongo->find("c", array("title"=>"asdqw"), array("start"=>2,"limit"=>2,"sort"=>array("id"=>1)))
    * 查找一条记录
    * $mongo->findOne("$mongo->findOne("ttt", array("id"=>1))", array("id"=>1));
    * 删除记录
    * $mongo->remove("ttt", array("title"=>"bbb"));
    * 仅删除一条记录
    * $mongo->remove("ttt", array("title"=>"bbb"), array("justOne"=>1));
    * 获取Mongo操作的错误信息
    * $mongo->getError();
    */
}