php文件下载IE文件名乱码问题

一直用chrome浏览器，没发现问题。今天用ie6，发现文件下载时文件名乱码，ie下迅雷下载文件名也是乱码。网上查了下说在ie下需要使用urlencode编码一下，我试了下

header('Content-Disposition: attachment; filename='. rawurlencode($file_name);

结果用ie下载还是乱码。php文件本身是gbk/gb2312编码，于是我先将$file_name转换成utf-8编码再进行urlencode

header('Content-Disposition: attachment; filename='. rawurlencode(iconv("GBK","UTF-8",$file_name)));

这样使用ie下载就没问题了，难道urlencode只能对utf-8进行转义编码？

还有就是获取远程文件的大小问题，php中的filesize函数只能对本地文件进行处理，处理远程文件会失败并发出一条警告,并且在windows平台传入的参数必须是gbk/gb2312编码，使用utf-8编码将无法访问系统中的资源。

在网上找了四种获取远程文件大小的方法，多谢前辈们的分享，记录一下：

方法一：header

<?php
get_headers($url,true);

//返回结果
Array
(
[0] => HTTP/1.1 200 OK
[Date] => Sat, 29 May 2004 12:28:14 GMT
[Server] => Apache/1.3.27 (Unix)  (Red-Hat/Linux)
[Last-Modified] => Wed, 08 Jan 2003 23:11:55 GMT
[ETag] => "3f80f-1b6-3e1cb03b"
[Accept-Ranges] => bytes
[Content-Length] => 438 
[Connection] => close
[Content-Type] => text/html
)
?>

这里可以根据Content-Length直接获取大小了。

方法二：curl

function remote_filesize($uri,$user='',$pw='')
{
// start output buffering
ob_start();
// initialize curl with given uri
$ch = curl_init($uri);
// make sure we get the header
curl_setopt($ch, CURLOPT_HEADER, 1);
// make it a http HEAD request
curl_setopt($ch, CURLOPT_NOBODY, 1);
// if auth is needed, do it here
if (!emptyempty($user) && !emptyempty($pw))
{
$headers = array('Authorization: Basic ' . base64_encode($user.':'.$pw));
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
}
$okay = curl_exec($ch);
curl_close($ch);
// get the output buffer
$head = ob_get_contents();
// clean the output buffer and return to previous
// buffer settings
ob_end_clean();

echo '<br>head-->'.$head.'<----end <br>';

// gets you the numeric value from the Content-Length
// field in the http header
$regex = '/Content-Length:\s([0-9].+?)\s/';
$count = preg_match($regex, $head, $matches);

// if there was a Content-Length field, its value
// will now be in $matches[1]
if (isset($matches[1]))
{
$size = $matches[1];
}
else
{
$size = 'unknown';
}
//$last=round($size/(1024*1024),3);
//return $last.' MB';
return $size;
}

方法三：fsock

function getFileSize($url)
{
$url = parse_url($url);
if($fp = @fsockopen($url['host'],emptyempty($url['port'])?80:$url['port'],$error))
{
fputs($fp,"GET ".(emptyempty($url['path'])?'/':$url['path'])." HTTP/1.1\r\n");
fputs($fp,"Host:$url[host]\r\n\r\n");
while(!feof($fp))
{
$tmp = fgets($fp);
if(trim($tmp) == '')
{
break;
}
elseif(preg_match('/Content-Length:(.*)/si',$tmp,$arr))
{
return trim($arr[1]);
}
}
return null;
}
else
{
return null;
}
}

方法四：file_get_contents

$fCont = file_get_contents("http://www.cnmiss.cn/");
echo strlen($fCont)/1024;