mydb.php

是个关于网格编程的程序

<?
class db{

var $linkid;
var $sqlid;
var $record;
function db($host="",$username="",$password="",$database="")
	{
	if(!$this->linkid)  @$this->linkid = mysql_connect($host, $username, $password) or die("连接服务器失败.");
	@mysql_select_db($database,$this->linkid) or die("无法打开数据库");
	return $this->linkid;}
function query($sql)
	{if($this->sqlid=mysql_query($sql,$this->linkid)) return $this->sqlid;
	else {
		$this->err_report($sql,mysql_error);
	return false;}
	}
function nr($sql_id="")
	{if(!$sql_id) $sql_id=$this->sqlid;
	return mysql_num_rows($sql_id);}

function nf($sql_id="")
	{if(!$sql_id) $sql_id=$this->sqlid;
	return mysql_num_fields($sql_id);}

function nextrecord($sql_id="")
	{if(!$sql_id) $sql_id=$this->sqlid;
	if($this->record=mysql_fetch_array($sql_id))  return $this->record;
	else return false;
	}

function f($name)
	{
	if($this->record[$name]) return $this->record[$name];
	else return false;
	}

function close() {mysql_close($this->linkid);}

function lock($tblname,$op="WRITE")
	{if(mysql_query("lock tables ".$tblname." ".$op)) return true; else return false;}

function unlock()
	{if(mysql_query("unlock tables")) return true; else return false;}

function ar() {
    return @mysql_affected_rows($this->linkid);
  }

function i_id() {
		return mysql_insert_id();
	}

function err_report($sql,$err)
	{
echo "Mysql查询错误<br>";
echo "查询语句：".$sql."<br>";
echo "错误信息：".$err;
	}
/****************************************类结束***************************/
}?>