PHP获取文件大小的几种方法!

一、get_header($url,true)：

$url = 'http://www.xxx.com/MoJing_win_x86_64_V5.125.zip';
$res = get_headers($url,true);
  echo "<pre>";
  print_R($res);
  die;
$filesize = round($res['Content-Length']//,);//四舍五入获取文件大小，单位M

image.png

二、curl：

$url = 'http://www.3d414.com/MoJing_win_x86_64_V5.125.zip';
echo getFileSize($url);die;//
function getFileSize($url,$user='',$pw='')
{
    ob_start();
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_HEADER, );
    curl_setopt($ch, CURLOPT_NOBODY, );
    if (!empty($user) && !empty($pw))
    {
        $headers = array('Authorization: Basic ' . base64_encode($user.':'.$pw));
        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
    }
    $okay = curl_exec($ch);
    curl_close($ch);
    $head = ob_get_contents();
    ob_end_clean();   

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

    $regex = '/Content-Length:\s([0-9].+?)\s/';
    $count = preg_match($regex, $head, $matches);
    $size = isset($matches[])?$matches[]:'unknown';
    //$last=round($size/(1024*1024),3);
    //return $last.' MB';
    return $size;
}  

三、fsockopen：

$url = 'http://www.xxx.com/MoJing_win_x86_64_V5.125.zip';
echo getFileSize($url);die;
function getFileSize($url)
{
    $url = parse_url($url);
    if($fp = @fsockopen($url['host'],empty($url['port'])?:$url['port'],$error))
    {
        fputs($fp,"GET ".(empty($url['path'])?'/':$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[]);
            }
        }
        return null;
    }
    else
    {
        return null;
    }
}  

filesize()，只能获取本地文件大小，不能获取远程文件大小：

$url = './v3.rar';//  获取本地文件
$url ='http://www.xxx.cc/v3.rar';//获取远程文件
echo filesize($url);

file_get_contents(),获取文件内容，strlen()获取内容大小：