【推荐】2019 Java 开发者跳槽指南.pdf(吐血整理) >>> 
<?php Class DB { private $link_id; private $handle; private $is_log; private $time; private $getLastSql; public function DB($dbhost='localhost',$dbuser='', $dbpw='', $dbname='' ) { if ($dbhost && $dbuser && $dbpw && $dbname) { $this->connect($dbhost,$dbuser, $dbpw, $dbname); } } //数据库连接 public function connect($dbhost, $dbuser, $dbpw, $dbname, $pconnect = 0,$charset='utf8') { if( $pconnect==0 ) { $this->link_id = @mysql_connect($dbhost, $dbuser, $dbpw, true); if(!$this->link_id){ $this->halt("数据库连接失败"); } } else { $this->link_id = @mysql_pconnect($dbhost, $dbuser, $dbpw); if(!$this->link_id){ $this->halt("数据库持久连接失败"); } } if(!@mysql_select_db($dbname,$this->link_id)) { $this->halt('数据库选择失败'); } @mysql_query("set names ".$charset); } //查询 public function query($sql) { $this->write_log("查询 ".$sql); $query = mysql_query($sql,$this->link_id); $this->getLastSql = $sql; if(!$query) $this->halt('Query Error: ' . $sql); return $query; } //获取一条记录（MYSQL_ASSOC，MYSQL_NUM，MYSQL_BOTH） public function get_one($sql,$result_type = MYSQL_ASSOC) { $query = $this->query($sql); $rt =& mysql_fetch_array($query,$result_type); $this->getLastSql = $sql; $this->write_log("获取一条记录 ".$sql); return $rt; } //获取一条记录（MYSQL_ASSOC，MYSQL_NUM，MYSQL_BOTH） public function get_row($sql,$result_type = MYSQL_ASSOC) { $query = $this->query($sql); $rt =& mysql_fetch_array($query,$result_type); $this->getLastSql = $sql; $this->write_log("获取一条记录 ".$sql); return $rt; } //获取全部记录 public function get_all($sql,$result_type = MYSQL_ASSOC) { $query = $this->query($sql); $i = 0; $rt = array(); while($row =& mysql_fetch_array($query,$result_type)) { $rt[$i]=$row; $i++; } $this->getLastSql = $sql; $this->write_log("获取全部记录 ".$sql); return $rt; } //获取全部记录 public function get_rows($sql,$result_type = MYSQL_ASSOC) { $query = $this->query($sql); $i = 0; $rt = array(); while($row =& mysql_fetch_array($query,$result_type)) { $rt[$i]=$row; $i++; } $this->getLastSql = $sql; $this->write_log("获取全部记录 ".$sql); return $rt; } //插入 public function insert($table,$dataArray) { $field = ""; $value = ""; if( !is_array($dataArray) || count($dataArray)<=0) { $this->halt('没有要插入的数据'); return false; } while(list($key,$val)=each($dataArray)) { $field .="$key,"; $value .="'$val',"; } $field = substr( $field,0,-1); $value = substr( $value,0,-1); $sql = "insert into $table($field) values($value)"; $this->write_log("插入 ".$sql); $this->getLastSql = $sql; if(!$this->query($sql)) return false; return true; } //更新 public function update( $table,$dataArray,$condition="") { if( !is_array($dataArray) || count($dataArray)<=0) { $this->halt('没有要更新的数据'); return false; } $value = ""; while( list($key,$val) = each($dataArray)) $value .= "$key = '$val',"; $value .= substr( $value,0,-1); $sql = "update $table set $value where 1=1 and $condition"; $this->write_log("更新 ".$sql); $this->getLastSql = $sql; if(!$this->query($sql)) return false; return true; } //删除 public function delete( $table,$condition="") { if( empty($condition) ) { $this->halt('没有设置删除的条件'); return false; } $sql = "delete from $table where 1=1 and $condition"; $this->write_log("删除 ".$sql); $this->getLastSql = $sql; if(!$this->query($sql)) return false; return true; } //返回结果集 public function fetch_array($query, $result_type = MYSQL_ASSOC){ $this->write_log("返回结果集"); return mysql_fetch_array($query, $result_type); } //获取记录条数 public function num_rows($results) { if(!is_bool($results)) { $num = mysql_num_rows($results); $this->write_log("获取的记录条数为".$num); return $num; } else { return 0; } } //释放结果集 public function free_result() { $void = func_get_args(); foreach($void as $query) { if(is_resource($query) && get_resource_type($query) === 'mysql result') { return mysql_free_result($query); } } $this->write_log("释放结果集"); } //获取最后插入的id public function insert_id() { $id = mysql_insert_id($this->link_id); $this->write_log("最后插入的id为".$id); return $id; } //关闭数据库连接 protected function close() { $this->write_log("已关闭数据库连接"); return @mysql_close($this->link_id); } //错误提示 private function halt($msg='') { $msg .= "\r\n".mysql_error(); $this->write_log($msg); die($msg); } //析构函数 public function __destruct() { $this->free_result(); $use_time = ($this-> microtime_float())-($this->time); $this->write_log("完成整个查询任务,所用时间为".$use_time); if($this->is_log){ fclose($this->handle); } } //写入日志文件 public function write_log($msg=''){ if($this->is_log){ $text = date("Y-m-d H:i:s")." ".$msg."\r\n"; fwrite($this->handle,$text); } } //获取毫秒数 public function microtime_float() { list($usec, $sec) = explode(" ", microtime()); return ((float)$usec + (float)$sec); } public function getLastSql() { return $this->getLastSql; } } ?>
/*
用法： **** 连接 $db=new DB($dbhost, $dbuser, $dbpw, $dbname);
*** 查询： get_one($sql); 查一条记录 get_row($sql); 查一条记录 （习惯用这个名）
get_all($sql); 查多条记录 get_rows($sql); 查多条记录
*** 操作更新 insert($table,$dataArray); 我喜欢，这样的insert update( $table,$dataArray,$condition="") ; $condition是字符串哟 delete( $table,$condition="")
*** 其它
insert_id(); //获取最后插入的id write_log(); //写入日志文件
$db->getLastSql(); //有点thinkphp的味道
这个类，写得有点简单。以后加上打印错误及事务处理，就最好了。
*/
来源：oschina
链接：https://my.oschina.net/u/733235/blog/685701