var$link_ready=false;
var$db_ready=false;
//setorreturnConnectionString 返回，或者设定连接字符串
functionconnection_string($connstr="")
{
if(""==$connstr)
{
//如果没有参数传入，返回已有的连接字符
return"Server=".$this->db_server.";DataBase=".$this->db_name.";UserID=".$this-
>db_user.";PassWord=".$this->db_passwd;
}
else
{
//否则，解析连接字符，初始化变量
preg_match_all("|([a-zA-Z0-9]*)=([a-zA-Z0-9]*);*|",$connstr, 
$tmparr,PREG_PATTERN_ORDER);
$this->db_server=(strtolower($tmparr[1][0])=="server")?$tmparr[2][0]:"";
$this->db_name =(strtolower($tmparr[1][1])=="database")?$tmparr[2][1]:"";
$this->db_user =(strtolower($tmparr[1][2])=="userid")?$tmparr[2][2]:"";
$this->db_passwd=(strtolower($tmparr[1][3])=="password")?$tmparr[2][3]:"";
//var_dump($tmparr);
if(""==$this->db_serveror""==$this->db_nameor""==$this->db_useror""==$this->db_passwd)
$this->conntstr_ready=false;//如果有其中一个以上变量被赋以空字符串"",准备未就绪
else
$this->conntstr_ready=true;
return$this->conntstr_ready;
}
}

//连接数据库，返回连接对象
functionconnect()
{
if(!$this->conntstr_ready)
{
if($this->debug){$this->debuginfo.="连接字符串无效！\r\n";}
return$this->link_ready;
}
if($this->db_link=@mysql_connect($this->db_server,$this->db_user,$this->db_passwd))
{
$this->link_ready=true;
return$this->link_ready;
}
}