需要名称为book的mysql数据库表
表中含有下列字段：
id下载的文件的唯一标识
downnum  点击数

first.php
<?while($myrow = @mysql_fetch_array($result))
{
?>
<TR>
<TD>
<?if(empty($myrow["downnum"])) echo "0"; else echo $myrow["downnum"]; ?>  
</TD>
<TD>
<a  href="ddload.php?purl=downfileurl&dnnum=<?echo $myrow['downnum'] ?>&id=<?echo $myrow['id']?>">click here download </a>
</TD>
</TR>
<?};?>
  
ddload.php
<?
  include("data.inc.php");
  if($incerror)
  {
  echo $incerror;
  exit;
  }
  if(empty($dnnum)) $dnnum = 1;
  else $dnnum ++;
  $sql = "update book set downnum ='$dnnum' where id =$id";
  mysql_query($sql);
  mysql_close($connect);
  header("location:$purl");
?>