一个mysql数据库连接类库

<?php /* * created on 2010-3-8 * make by:suniteboy * my first mysql class * */ class mysql{ private $server =""; private $user =""; private $pwd =""; private $database =""; private $linkmode = 1; //连接模式，0表示普通连接，1表示永久连接 private $conn = 0; private $sql =""; //sql语句 private $result =""; //query查询结果 private $record =""; //保存记录 //============================================ // 构造函数 //============================================ public function __construct($server,$user,$pwd,$database,$charset="utf8",$linkmode=0) { if(emptyempty ( $server )| emptyempty( $user ) | emptyempty( $database )) { $this->show_error("连接信息不完整,请检查是否提供了服务器地址,用户名以及连接的数据库信息"); return 0; } $this->server = $server; $this->user = $user; $this->pwd = $pwd; $this->database = $database; $this->charset = $charset; $this->linkmode = $linkmode; $this->connect(); } //============================================ // 连接函数 //============================================ public function connect() { $this->conn = $this->linkmode?mysql_pconnect($this->server,$this->user,$this->pwd): mysql_connect($this->server,$this->user,$this->pwd); if(!$this->conn) { $this->show_error('无法连接服务器'); return 0; } if(!mysql_select_db($this->database)) { $this->show_error('无法连接数据库'.$this->database); return 0; } // $this->query('set names '.$this->charset); return $this->conn; } //============================================ // mysql查询函数 //============================================ public function query($sql) { if(emptyempty($sql)) { $this->show_error('sql语句为空'); return 0; } $this->sql = preg_replace('/ {2,}/',' ',trim($sql)); $this->result = mysql_query($this->sql,$this->conn); if(!$this->result) { $this->show_error('sql语句错误',true); return 0; } return $this->result; } //============================================ // 函数 //============================================ public function select_db($dbname) { return mysql_select_db($dbname); } public function fetch_array($query,$result_type=mysql_assoc) { return mysql_fetch_array($query,$result_type); } public function fetch_row($query) { return mysql_fetch_row($query); } //============================================ // 取得前一次mysql操作所影响到的记录行数 //============================================ public function affected_rows() { return mysql_affected_rows(); } public function num_fields($query) { return mysql_num_fields($query); } public function num_rows($query) { return @mysql_num_rows($query); } public function insert_id() { return mysql_insert_id(); } public function close() { return mysql_close(); } //============================================ // 从记录中取出一条结果 //============================================ public function getone($sql) { $res = $this->query($sql); if($res!==false) { $row = mysql_fetch_row($res); if($row!==false) { return $row; } else { return ''; } } else { return false; } } //============================================ // 从记录中取出所有结果 //============================================ public function getall($sql) { $res = $this->query($sql); if($res!==false) { $arr = array(); while($row = mysql_fetch_assoc($res)) { $arr[] = $row; } return $arr; } else { return false; } } //============================================ // 错误提示函数 //============================================ public function show_error($msg='',$sql=false) { $err = '['.mysql_errno().']'.mysql_error(); if($sql) $sql='sql语句:'.$this->sql; if($msg=='') { echo $err; echo "</br>"; } elseif($sql &&$msg) {//开源代码phpfensi.com echo $msg; echo "</br>"; echo $sql; } else { echo $msg; echo "</br>"; } } } ?>