一个简单记事本--php操作mysql辅助类创建

//SqlHelper.class.php
<?php
class SqlHelper{
    public $conn;
    public $host="localhost";
    public $user="root";
    public $passwrd="passwd";
    public $db="notebook";
    function __construct(){
        $this->conn=mysql_connect($this->host,$this->user,$this->passwrd);
        if(!$this->conn){
           die("连接失败".mysql_error()); 
        }
        mysql_select_db($this->db);
        mysql_query("set names utf8");
    }
    //增删改
    function execute_dml($sql){
       $b=mysql_query($sql);
       if(!$b){
           return 0;
           //die("操作失败".mysql_error());
       }else if(mysql_affected_rows($this->conn)>0){
           return 1;
       }else{
           return 2;
       }
    }
    //查询，多条结果
    function execute_dql($sql){
        $arr=array();
        $res=mysql_query($sql);
        $i=0;
        while($row=mysql_fetch_assoc($res)){
            $arr[$i++]=$row;
        }
        mysql_free_result($res);
        return $arr;
    }
    //查询，单条结果
    function execute_dql2($sql){
        $res=mysql_query($sql);
        return $res;
    }
    function conn_close(){
        if(!empty($this->conn)){
            mysql_close($this->conn);
        }
    }  
}