<?php
// 连接数据库
class Db {
 static public function getDB() {
  try {
   $pdo = new PDO(DB_DSN, DB_USER, DB_PWD);
   $pdo->setAttribute(PDO::ATTR_PERSISTENT, true); // 设置数据库连接为持久连接
   $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); // 设置抛出错误
   $pdo->setAttribute(PDO::ATTR_ORACLE_NULLS, true); // 设置当字符串为空转换为 SQL 的 NULL
   $pdo->query('SET NAMES utf8'); // 设置数据库编码
  } catch (PDOException $e) {
   exit('数据库连接错误，错误信息：'. $e->getMessage());
  }
  return $pdo;
 }
}
?>

<?php
/**
* 数据库操作类库
* author Lee.
* Last modify $Date: 2012-1-19 13:59；04 $
*/
class M {
 private $_db; //数据库句柄
 public $_sql; //SQL语句
 /**
  * 构造方法
  */
 public function __construct() {
  $this->_db = Db::getDB();
 }
 /**
  * 数据库添加操作
  * @param string $tName 表名
  * @param array $field 字段数组
  * @param array $val 值数组
  * @param bool $is_lastInsertId 是否返回添加ID
  * @return int 默认返回成功与否，$is_lastInsertId 为true，返回添加ID
  */
 public function insert($tName, $fields, $vals, $is_lastInsertId=FALSE) {
  try {
   if (!is_array($fields) || !is_array($vals))
    exit($this->getError(__FUNCTION__, __LINE__));
   $fields = $this->formatArr($fields);
   $vals = $this->formatArr($vals, false);
   $tName = $this->formatTabName($tName);
   $this->_sql = "INSERT INTO {$tName} ({$fields}) VALUES ({$vals})";
   if (!$is_lastInsertId) {
    $row = $this->_db->exec($this->_sql);
    return $row;
   } else {
    $this->_db->exec($this->_sql);
    $lastId = (int)$this->_db->lastInsertId();
    return $lastId;
   }
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 数据库修改操作
  * @param string $tName 表名
  * @param array $field 字段数组
  * @param array $val 值数组
  * @param string $condition 条件
  * @return int 受影响的行数
  */
 public function update($tName, $fieldVal, $condition) {
  try {
   if (!is_array($fieldVal) || !is_string($tName) || !is_string($condition))
    exit($this->getError(__FUNCTION__, __LINE__));
   $tName = $this->formatTabName($tName);
   $upStr = '';
   foreach ($fieldVal as $k=>$v) {
    $upStr .= '`'.$k . '`=' . '\'' . $v . '\'' . ',';
   }
   $upStr = rtrim($upStr, ',');
   $this->_sql = "UPDATE {$tName} SET {$upStr} WHERE {$condition}";
   $row = $this->_db->exec($this->_sql);
   return $row;
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 数据库删除操作（注：必须添加 where 条件）
  * @param string $tName 表名
  * @param string $condition 条件
  * @return int 受影响的行数
  */
 public function del($tName, $condition) {
  try {
   if (!is_string($tName) || !is_string($condition))
    exit($this->getError(__FUNCTION__, __LINE__));
   $tName= $this->formatTabName($tName);
   $this->_sql = "DELETE FROM {$tName} WHERE {$condition}";
   $row = $this->_db->exec($this->_sql);
   return $row;
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 返回表总个数
  * @param string $tName 表名
  * @param string $condition 条件
  * @return int
  */
 public function total($tName, $condition='') {
  try {
   if (!is_string($tName))
    exit($this->getError(__FUNCTION__, __LINE__));
   $tName = $this->formatTabName($tName);
   $this->_sql = "SELECT COUNT(*) AS total FROM {$tName}" .
   ($condition=='' ? '' : ' WHERE ' . $condition);
   $re = $this->_db->query($this->_sql);
   foreach ($re as $v) {
    $total = $v['total'];
   }
   return (int)$total;
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 数据库删除多条数据
  * @param string $tName 表名
  * @param string $field 依赖字段
  * @param array $ids 删除数组
  * @return int 受影响的行数
  */
 public function delMulti($tName, $field, $ids) {
  try {
   if (!is_string($tName) || !is_array($ids))
    exit($this->getError(__FUNCTION__, __LINE__));
   $delStr = '';
   $tName = $this->formatTabName($tName);
   $field = $this->formatTabName($field);
   foreach ($ids as $v) {
    $delStr .= $v . ',';
   }
   $delStr = rtrim($delStr, ',');
   $this->_sql = "DELETE FROM {$tName} WHERE {$field} IN ({$delStr})";
   $row = $this->_db->exec($this->_sql);
   return $row;
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 获取表格的最后主键（注：针对 INT 类型）
  * @param string $tName 表名
  * @return int
  */
 public function insertId($tName) {
  try {
   if (!is_string($tName))
    exit($this->getError(__FUNCTION__, __LINE__));
   $this->_sql = "SHOW TABLE STATUS LIKE '{$tName}'";
   $result = $this->_db->query($this->_sql);
   $insert_id = 0;
   foreach ($result as $v) {
    $insert_id = $v['Auto_increment'];
   }
   return (int)$insert_id;
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 检查数据是否已经存在（依赖条件）
  * @param string $tName 表名
  * @param string $field 依赖的字段
  * @return bool
  */
 public function exists($tName, $condition) {
  try {
   if (!is_string($tName) || !is_string($condition))
    exit($this->getError(__FUNCTION__, __LINE__));
   $tName = $this->formatTabName($tName);
   $this->_sql = "SELECT COUNT(*) AS total FROM {$tName} WHERE {$condition}";
   $result = $this->_db->query($this->_sql);
   foreach ($result as $v) {
     $b = $v['total'];
   }
   if ($b) {
    return true;
   } else {
    return false;
   }
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 检查数据是否已经存在（依赖 INT 主键）
  * @param string $tName 表名
  * @param string $primary 主键
  * @param int $id 主键值
  * @return bool
  */
 public function existsByPK($tName, $primary, $id) {
  try {
   if (!is_string($tName) || !is_string($primary)
   || !is_int($id))
    exit($this->getError(__FUNCTION__, __LINE__));
   $tName = $this->formatTabName($tName);
   $this->_sql = "SELECT COUNT(*) AS total FROM {$tName} WHERE {$primary} = ". $id;
   $result = $this->_db->query($this->_sql);
   foreach ($result as $v) {
     $b = $v['total'];
   }
   if ($b) {
    return true;
   } else {
    return false;
   }
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 预处理删除（注：针对主键为 INT 类型，推荐使用）
  * @param string $tName 表名
  * @param string $primary 主键字段
  * @param int or array or string $ids 如果是删除一条为 INT，多条为 array，删除一个范围为 string
  * @return int 返回受影响的行数
  */
 public function delByPK($tName, $primary, $ids, $mult=FALSE) {
  try {
   if (!is_string($tName) || !is_string($primary)
   || (!is_int($ids) && !is_array($ids) && !is_string($ids))
   || !is_bool($mult)) exit($this->getError(__FUNCTION__, __LINE__));
   $tName = $this->formatTabName($tName);
   $stmt = $this->_db->prepare("DELETE FROM {$tName} WHERE {$primary}=?");
   if (!$mult) {
    $stmt->bindParam(1, $ids);
    $row = $stmt->execute();
   } else {
    if (is_array($ids)) {
     $row = 0;
     foreach ($ids as $v) {
      $stmt->bindParam(1, $v);
      if ($stmt->execute()) {
       $row++;
      }
     }
    } elseif (is_string($ids)) {
     if (!strpos($ids, '-'))
      exit($this->getError(__FUNCTION__, __LINE__));
     $split = explode('-', $ids);
     if (count($split)!=2 || $split[0]>$split[1])
      exit($this->getError(__FUNCTION__, __LINE__));
     $i = null;
     $count = $split[1]-$split[0]+1;
     for ($i=0; $i<$count; $i++) {
      $idArr[$i] = $split[0]++;
     }
     $idStr = '';
     foreach ($idArr as $id) {
      $idStr .= $id . ',';
     }
     $idStr = rtrim($idStr, ',');
     $this->_sql ="DELETE FROM {$tName} WHERE {$primary} in ({$idStr})";
     $row = $this->_db->exec($this->_sql);
    }
   }
   return $row;
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 返回单个字段数据或单条记录
  * @param string $tName 表名
  * @param string $condition 条件
  * @param string or array $fields 返回的字段，默认是*
  * @return string || array
  */
 public function getRow($tName, $condition='', $fields="*") {
  try {
   if (!is_string($tName) || !is_string($condition)
   || !is_string($fields) || empty($fields))
     exit($this->getError(__FUNCTION__, __LINE__));
   $tName = $this->formatTabName($tName);
   $this->_sql = "SELECT {$fields} FROM {$tName} ";
   $this->_sql .= ($condition=='' ? '' : "WHERE {$condition}") . " LIMIT 1";
   $sth = $this->_db->prepare($this->_sql);
   $sth->execute();
   $result = $sth->fetch(PDO::FETCH_ASSOC);
   if ($fields === '*') {
    return $result;
   } else {
    return $result[$fields];
   }
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 返回多条数据
  * @param string $tName 表名
  * @param string $fields 返回字段，默认为*
  * @param string $condition 条件
  * @param string $order 排序
  * @param string $limit 显示个数
  * @return PDOStatement
  */
 public function getAll($tName, $fields='*', $condition='', $order='', $limit='') {
  try {
   if (!is_string($tName) || !is_string($fields)
   || !is_string($condition) || !is_string($order)
   || !is_string($limit))
    exit($this->getError(__FUNCTION__, __LINE__));
   $tName = $this->formatTabName($tName);
   $fields = ($fields=='*' || $fields=='') ? '*' : $fields;
   $condition = $condition=='' ? '' : " WHERE ". $condition ;
   $order = $order=='' ? '' : " ORDER BY ". $order;
   $limit = $limit=='' ? '' : " LIMIT ". $limit;
   $this->_sql = "SELECT {$fields} FROM {$tName} {$condition} {$order} {$limit}";
   $sth = $this->_db->prepare($this->_sql);
   $sth->execute();
   $result = $sth->fetchAll(PDO::FETCH_ASSOC);
   return $result;
  } catch (PDOException $e) {
   exit($e->getMessage());
  }
 }
 /**
  * 格式化数组（表结构和值）
  * @param array $field
  * @param bool $isField
  * @return string
  */
 private function formatArr($field, $isField=TRUE) {
  if (!is_array($field)) exit($this->getError(__FUNCTION__, __LINE__));
  $fields = '';
  if ($isField) {
   foreach ($field as $v) {
    $fields .= '`'.$v.'`,';
   }
  } else {
   foreach ($field as $v) {
    $fields .= '\''.$v.'\''.',';
   }
  }
  $fields = rtrim($fields, ',');
  return $fields;
 }
 /**
  * 格式化问号
  * @param int $count 数量
  * @return string 返回格式化后的字符串
  */
 private function formatMark($count) {
  $str = '';
  if (!is_int($count)) exit($this->getError(__FUNCTION__, __LINE__));
  if ($count==1) return '?';
  for ($i=0; $i<$count; $i++) {
   $str .= '?,';
  }
  return rtrim($str, ',');
 }
 /**
  * 错误提示
  * @param string $fun
  * @return string
  */
 private function getError($fun, $line) {
  return __CLASS__ . '->' . $fun . '() line<font color="red">'. $line .'</font> ERROR!';
 }
 /**
  * 处理表名
  * @param string $tName
  * @return string
  */
 private function formatTabName($tName) {
  return '`' . trim($tName, '`') . '`';
 }
 /**
  * 析构方法
  */
 public function __destruct() {
  $this->_db = null;
 }
}