php类

<?php

class mysql{

    private $host ;    

private $user = "root";   

  private $pwd = "";  

   private $db = "bbs";   

  private $charset = "utf8";   

  private $conn = "";

    public function __construct($host="127.0.0.1",$user="root",$pwd="",$db="bbs",$charset="utf8"){    

     $this->host = $host;   

      $this->user = $user;     

    $this->pwd = $pwd;     

    $this->db = $db;     

    $this->charset = $charset;    

     $this->conn = get_conn();   

  }

    public function get_conn(){     

    //像下面这种写代码的方式，一般俗称 硬代码     

    //好的程序习惯是，可以设置为变量，那么一定要设置为变量   

      //可以设置为常量，那么最好设置为常量 //    

    mysql_connect("127.0.0.1","root","root");

        $conn = mysql_connect($this->host,$this->user,$this->pwd) or die(mysql_error());     

    mysql_select_db($this->db,$this->conn);     

    mysql_query("set names '$this->charset'");

        return $conn;  

   }

    public function myquery($sql){    

     $result = mysql_query($sql);      

   return $result;   

  }

    public function delete($sql){

        $this->myquery($sql);    

     return mysql_affected_rows();

//如果执行删除成功,那么肯定有受影响的行数 //    

    return $result;   

  }

    public function insert($sql){

    }

}

$mysql = new mysql("127.0.0.1","root","","bbs","utf8");

//$mysql->host = "127.0.0.1";

?>