<?phpheader("Content-Type:text/html;charset=utf-8");class PdoMysql{  public static $config = array();//設置連接參數，配置信息  public static $link = null;//保存連接標識符  public static $pconnect = false;//是否開啟長連接  public static $dbVersion = null;//保存數據庫版本  public static $connected = false;//判斷是否連接成功  public static $PDOStatement = null;//保證PDOStatement對象  public static $queryStr = null;//保存最后執行的操作  public static $error = null;//保存錯誤信息  public static $lastInsertId = null;//保存上一步插入操作保存的AUTO_INCREMANT  public static $numRows = null;//受影響記錄的條數  /**   * 構造函數，連接數據庫   *   * @param   array|string $dbConfig The database configuration   *   * @return   boolean    ( description_of_the_return_value )   */  public function __construct($dbConfig=''){    if(!class_exists("PDO")){      self::throw_exception("不支持PDO,請先開啟");    }    if(!is_array($dbConfig)){      $dbConfig = array(              'hostname' => 'localhost',              'username' => 'root',              'password' => '1234',              'database' => 'test',              'hostport' => '3306',              'dbms'   => 'mysql',              'dsn'   => 'mysql:host=localhost;dbname=test'            );    }    if(empty($dbConfig['hostname'])){      self::throw_exception("沒有定義數據庫配置,請先定義");    }    self::$config = $dbConfig;    if(empty(self::$config['params'])){      self::$config['params'] = array();    }    if(!isset(self::$link)){      $configs = self::$config;      if(self::$pconnect){        //開啟長連接,添加到配置數組中        $configs['params'][constant("PDO::ATTR_PERSISTENT")] = true;      }      try {        self::$link = new PDO($configs['dsn'],$configs['username'],$configs['password'],$configs['params']);      } catch (PDOException $e) {        self::throw_exception($e->getMessage());      }      if(!self::$link){        self::throw_exception("PDO連接錯誤");        return false;      }      self::$link->exec("set names utf8");      self::$dbVersion = self::$link->getAttribute(constant("PDO::ATTR_SERVER_VERSION"));      unset($configs);    }  }  /**   * 得到所有記錄   *   * @param   <type> $sql  The sql   *   * @return   <type> All.   */  public static function getAll($sql=null){    if($sql!=null){      self::query($sql);    }    $result = self::$PDOStatement->fetchAll(constant("PDO::FETCH_ASSOC"));    return $result;  }  /**   * 得到一條記錄   *   * @param   <type> $sql  The sql   *   * @return   <type> The row.   */  public static function getRow($sql=null){    if($sql!=null){      self::query($sql);    }    $result = self::$PDOStatement->fetch(constant("PDO::FETCH_ASSOC"));    return $result;  }  /**   * 執行增刪改操作，返回受影響記錄的條數   *   * @param   <type>  $sql  The sql   *   * @return   boolean ( description_of_the_return_value )   */  public static function execute($sql=null){    $link = self::$link;    if(!$link)return false;    if($sql!=null){      self::$queryStr = $sql;    }    if(!empty(self::$PDOStatement))self::free();    $result = $link->exec(self::$queryStr);    self::haveErrorThrowException();    if($result){      self::$lastInsertId = $link->lastInsertId();      self::$numRows = $result;      return $result;    }else{      return false;    }  }  /**   * 根據主鍵查找記錄   *   * @param   <type> $tabName The tab name   * @param   <type> $priId  The pri identifier   * @param   string $fields  The fields   *   * @return   <type> ( description_of_the_return_value )   */  public static function findById($tabName,$priId,$fields='*'){    $sql = 'SELECT %s FROM %s WHERE id=%d';    return self::getRow(sprintf($sql,self::parseFields($fields),$tabName,$priId));  }  /**   * 執行普通查詢   *   * @param   <type> $tables The tables   * @param   <type> $where  The where   * @param   string $fields The fields   * @param   <type> $group  The group   * @param   <type> $having The having   * @param   <type> $order  The order   * @param   <type> $limit  The limit   *   * @return   <type> ( description_of_the_return_value )   */  public static function find($tables,$where=null,$fields='*',$group=null,$having=null,$order=null,$limit    =null){    $sql = 'SELECT '.self::parseFields($fields).' FROM '.$tables    .self::parseWhere($where)    .self::parseGroup($group)    .self::parseHaving($having)    .self::parseOrder($order)    .self::parseLimit($limit);    $data = self::getAll($sql);    return $data;  }  /**   * 添加記錄   *   * @param   <type> $data  The data   * @param   <type> $table The table   *   * @return   <type> ( description_of_the_return_value )   */  public static function add($data,$table){    $keys = array_keys($data);    array_walk($keys, array('PdoMySQL','addSpecialChar'));    $fieldsStr = join(',',$keys);    $values = "'".join("','",array_values($data))."'";    $sql = "INSERT {$table}({$fieldsStr}) VALUES({$values})";    return self::execute($sql);  }  /**   * 更新數據   *   * @param   <type> $data  The data   * @param   <type> $table The table   * @param   <type> $where The where   * @param   <type> $order The order   * @param   <type> $limit The limit   */  public static function update($data,$table,$where=null,$order=null,$limit=null){    $sets = '';    foreach ($data as $key => $value) {      $sets .= $key."='".$value."',";    }    $sets = rtrim($sets,',');    $sql = "UPDATE {$table} SET {$sets}".self::parseWhere($where).self::parseOrder($order).self::parseLimit($limit);    echo $sql;  }  /**   * 刪除數據   *   * @param   <type> $data  The data   * @param   <type> $table The table   * @param   <type> $where The where   * @param   <type> $order The order   * @param   <type> $limit The limit   *   * @return   <type> ( description_of_the_return_value )   */  public static function delete($table,$where=null,$order=null,$limit=null){    $sql = "DELETE FROM {$table} ".self::parseWhere($where).self::parseOrder($order).self::parseLimit($limit);    return self::execute($sql);  }  /**   * 執行查詢   *   * @param   string  $sql  The sql   *   * @return   boolean ( description_of_the_return_value )   */  public static function query($sql=''){    $link = self::$link;    if(!$link)return false;    //判斷之前是否有結果集，如果有的話，釋放結果集    if(!empty(self::$PDOStatement))self::free();    self::$queryStr = $sql;    self::$PDOStatement = $link->prepare(self::$queryStr);    $res = self::$PDOStatement->execute();    self::haveErrorThrowException();    return $res;  }  /**   * 獲取最后執行的sql   *   * @return   boolean The last sql.   */  public static function getLastSql(){    $link = self::$link;    if(!$link){      return false;    }    return self::$queryStr;  }  /**   * 獲取最后插入的ID   *   * @return   boolean The last insert identifier.   */  public static function getLastInsertId(){    $link = self::$link;    if(!$link){      return false;    }    return self::$lastInsertId;  }  /**   * 獲得數據庫的版本   *   * @return   boolean The database version.   */  public static function getDbVersion(){    $link = self::$link;    if(!$link){      return false;    }    return self::$dbVersion;  }  /**   * 得到數據庫中表   *   * @return   array ( description_of_the_return_value )   */  public static function showTables(){    $tables = array();    if(self::query("show tables")){      $result = self::getAll();      foreach ($result as $key => $value) {        $tables[$key] = current($value);      }    }    return $tables;  }  /**   * 解析where條件   *   * @param   <type> $where The where   *   * @return   <type> ( description_of_the_return_value )   */  public static function parseWhere($where){    $whereStr = '';    if(is_string($where)&&!empty($where)){      $whereStr = $where;    }    return empty($whereStr) ? '' : ' WHERE '.$whereStr;  }  /**   * 解析group   *   * @param   <type> $group The group   *   * @return   <type> ( description_of_the_return_value )   */  public static function parseGroup($group){    $groupStr = '';    if(is_array($group)){      $groupStr = implode(',', $group);    }elseif(is_string($group)&&!empty($group)){      $groupStr = $group;    }    return empty($groupStr) ? '' : ' GROUP BY '.$groupStr;  }  /**   * 解析having   *   * @param   <type> $having The having   *   * @return   <type> ( description_of_the_return_value )   */  public static function parseHaving($having){    $havingStr = '';    if(is_string($having)&&!empty($having)){      $havingStr = $having;    }    return empty($havingStr) ? '' : ' HAVING '.$havingStr;  }  /**   * 解析order   *   * @param   <type> $order The order   *   * @return   <type> ( description_of_the_return_value )   */  public static function parseOrder($order){    $orderStr = '';    if(is_string($order)&&!empty($order)){      $orderStr = $order;    }    return empty($orderStr) ? '' : ' ORDER BY '.$orderStr;  }  /**   * 解析limit   *   * @param   <type> $limit The limit   *   * @return   <type> ( description_of_the_return_value )   */  public static function parseLimit($limit){    $limitStr = '';    if(is_array($limit)){      $limitStr = implode(',', $limit);    }elseif(is_string($limit)&&!empty($limit)){      $limitStr = $limit;    }    return empty($limitStr) ? '' : ' LIMIT '.$limitStr;  }  /**   * 解析字段   *   * @param   <type> $fields The fields   *   * @return   string ( description_of_the_return_value )   */  public static function parseFields($fields){    if(is_array($fields)){      array_walk($fields, array('PdoMySQL','addSpecialChar'));      $fieldsStr = implode(',', $fields);    }elseif (is_string($fields)&&!(empty($fields))) {      if(strpos($fields, '`')===false){        $fields = explode(',', $fields);        array_walk($fields, array('PdoMySQL','addSpecialChar'));        $fieldsStr = implode(',', $fields);      }else{        $fieldsStr = $fields;      }    }else{      $fieldsStr = "*";    }    return $fieldsStr;   }  /**   * 通過反引號引用字字段   *   * @param   string $value The value   *   * @return   string ( description_of_the_return_value )   */  public static function addSpecialChar(&$value){    if($value==="*"||strpos($value,'.')!==false||strpos($value,'`')!==false){      //不用做處理    }elseif(strpos($value, '`')===false){      $value = '`'.trim($value).'`';    }    return $value;  }  /**   * 釋放結果集   */  public static function free(){    self::$PDOStatement = null;  }  /**   * 拋出錯誤信息   *   * @return   boolean ( description_of_the_return_value )   */  public static function haveErrorThrowException(){    $obj = empty(self::$PDOStatement) ? self::$link : self::$PDOStatement;    $arrError = $obj->errorInfo();    if($arrError[0]!='00000'){      self::$error = 'SQLSTATE=>'.$arrError[0].'<br/>SQL Error=>'.$arrError[2].'<br/>Error SQL=>'.self::$queryStr;      self::throw_exception(self::$error);      return false;    }    if(self::$queryStr==''){      self::throw_exception('沒有執行SQL語句');      return false;    }  }  /**   * 自定義錯誤處理   *   * @param   <type> $errMsg The error message   */  public static function throw_exception($errMsg){    echo $errMsg;  }  /**   * 銷毀連接對象，關閉數據庫   */  public static function close(){    self::$link = null;  }}$pdo = new PdoMysql();var_dump($pdo->showTables());