一个PHP数据库操作类源码

class Core{
  /*对数组进行继承*/
  static function inHerit($arr_orgin,$arr_output){
    return array_merge($arr_orgin,$arr_output);
 
  }

  /*打印错误*/
  static function throwError($errmsg){
    echo '

error:'.$errmsg.'

';
    exit();
  }
}
?>
class db{
    private $result = array();
    private $connector = array();
    private $configs = array();
    private $active = 0;
    private $default_config = array(
        'dbtype' => 'mysql',
          'index' => 0,'user' => 'root', 'pwd' => '' ,'host' => 'localhost' ,'port'=> 3306,'charset' => 'utf8' ,'dbname' => null
    );
   
   /*初始化*/
   public function __construct($config = array()){
     if($config) $this->connect($config);
   }

   public function __destruct(){
       foreach($this->connector as $index => $connect)
           $this->{'_'.$this->configs[$index]['dbtype'].'_close'}($connect);
           
   }

   private function _mysql_close($connect){
      mysqli_close($connect);
   }
   /*选择连接*/
   public function selectConnect($index){
        return  isset($this->connector[$index]) && (($this->active = $index) || true);
   }
   /*建立连接*/
   public function connect($config){
     (!isset($config['index'])) && $config['index'] = $this->default_config['index']++  ;

     $config = Core::inHerit($this->default_config,$config);
     !in_array($config['dbtype'],array('mysql')) &&  Core::throwError('未支持的数据库类型');
     extract($config);
     $this->configs[$index] = $config;
     $this->{'_'.$config['dbtype'].'_connect'}($user, $pwd,$host,$dbname,$charset,$index,$port);
   
   }
   private function _mysql_connect($user = 'root', $pwd = '' ,$host = 'localhost' ,$dbname = null,$charset = 'utf8' ,$index = 0 ,$port = 3306){
     $this->connector[$index] =  mysqli_connect ( $host, $user, $pwd , null, $port) or Core::throwError(mysql_error());
     $this->active = $index;
     if($dbname) $this->selectDb($dbname,$charset);
   }
  
   /*取得当前连接*/
   private function _getConnect(){
     return $this->connector[$this->active];
   }
   /*取得当前连接使用的数据库类型 带参数自动拼接为函数名*/
   private function _getDbTypeFunc($funcname = null){
     $dbtype = $this->configs[$this->active]['dbtype'];
     return $funcname?'_'.$dbtype.'_'.$funcname:$dbtype;
   }
   /*选择数据库*/
   public function selectDb($dbname,$charset){
     mysqli_select_db($this->_getConnect(),$dbname) or Core::throwError(mysql_error());
     $this->_mysql_query('set names '.$charset);
   }
  
   /*执行语句*/
   private function _mysql_query($sql){
    $result = mysqli_query($this->_getConnect(),$sql) or Core::throwError(mysql_error());
    return $result;
   }

   private function _mysql_bind_by_name($sql , $sqlv){
        $sql_param = array();
       
        $getparam = $getparam2 =   '\w+?';// $getparam = array_keys($sqlv); implode('|',$getparam);
        preg_match_all('/:('.$getparam.')\b/iU',$sql,$getparam) or   Core::throwError('参数绑定错误');
       
        $getparam = $getparam[1];
        $getparam = array_flip($getparam);

        count($getparam) != count($sqlv) || array_diff_key($getparam,$sqlv) &&  Core::throwError('参数不匹配');

        $sql = preg_replace('/:('.$getparam2.')\b/iU','?',$sql)  ;
               
        $sqlv = array_merge($getparam,$sqlv);
       
        unset($getparam2);
        unset($getparam);
       
       
        $stmt = mysqli_prepare($this->_getConnect(),$sql) or Core::throwError('wrong sql:'.$sql);
       
       
        $ptype = '';
        $bindparam = array($stmt,'');
   
        foreach ($sqlv as $k => $v){
            $ptype .= $this->_getParamType($k);
            $bindparam[] = $v;
            }
        $bindparam[1] = $ptype;
   
        call_user_func_array('mysqli_stmt_bind_param',$bindparam);
        return $this->_mysql_stmt_exec($stmt,$sql);
   }

   private function _mysql_bind_in_sort(){
       $argus = func_get_args() ;
       $sql = array_shift($argus);
       $stmt = mysqli_prepare($this->_getConnect(),$sql) or Core::throwError('wrong sql:'.$sql);
       $pcount = mysqli_stmt_param_count($stmt);
      
       $pcount != count($argus)  && Core::throwError('参数不匹配');
       $ptype = str_repeat('s',$pcount);
       array_splice($argus, 0, 0 ,array($stmt,$ptype));
       call_user_func_array('mysqli_stmt_bind_param',$argus);

       return $this->_mysql_stmt_exec($stmt,$sql);
   }

   private function _mysql_stmt_exec($stmt,$sql){
         mysqli_stmt_execute($stmt);

        if($this->isSelect($sql)){ ///返回值绑定
           
            mysqli_stmt_bind_result($stmt,$a);
             while ($stmt->fetch()) {
                    print_r($a);
                    echo '
';
                }
         }
         $stmt->close();
  
   }

   /*根据参数形式使用不同函数*/
   private function _mysql_iquery($sql , $sqlv = array()){
     if ($sqlv){
         if (is_array($sqlv))
             return  $this->_mysql_bind_by_name($sql , $sqlv);
         else{
             $argus = func_get_args() ;
             return call_user_func_array(array($this,'_mysql_bind_in_sort'),$argus);
         }
     }else{
         return $this->_mysql_query($sql,$sqlv);
     }
   }
 
  /*根据键名前缀区分数据类型*/
  private function _getParamType($key){
     $r = 's';
     /*首字母小写 第二个字母大写 则第一个字母为模式前缀*/
     $mode = array(
       'i' => 'i','s' => 's','d' => 'd','b' => 'b'   
     );
     if (strlen($key) >= 2 &&  $key[0] == strtolower($key[0]) && $key[1] == strtoupper($key[1]) && in_array($key[0],$mode))
        $r = $mode[$key[0]];
   
     return $r;
  }
 /*分析sql语句 判断行为*/
  private function _cmdType($sql){
      return substr(strtolower($sql),0,strpos($sql,' '));
       
   }
   /*分析sql语句是否为select语句*/
   private function isSelect($sql){
        return  'select' == $this->_cmdType($sql);
   }
   public function query($sql , $sqlv = array()){
       $func = $this->_getDbTypeFunc('iquery');
      
       $argus = func_get_args() ;
       $argus[0] = trim($argus[0]);
       return call_user_func_array(array($this,$func),$argus);
   }
 
}
?>

$d = array(
  'dbname' => 'test',
  'charset' => 'latin1'
  );
$db = new db($d);

//数组方式绑定参数
$sqlv = array('iId1'=>'14','id2' => 30);
$r = $db -> query("select id from toselect where   id > :iId1 and id

//标准方式绑定参数
$r = $db -> query("select content from toselect where   id > ? ",13);

var_dump($r);
?>