<?php
if(isset($_GET["file"])){
   downFile(realpath($_GET["file"]));
}
else
{
   echo("请输入文件路径!");
}
function downFile($sFilePath)
{
   if(file_exists($sFilePath)){
       $aFilePath=explode("/",str_replace("\\","/",$sFilePath),$sFilePath);
       $sFileName=$aFilePath[count($aFilePath)-1];
       $nFileSize=filesize ($sFilePath);
       header ("Content-Disposition: attachment; filename=" . $sFileName);
       header ("Content-Length: " . $nFileSize);
       header ("Content-type: application/octet-stream");
       readfile($sFilePath);
   }
   else
   {
       echo("文件不存在!");
   }
}
?>