用PHP从MySQL中下载二进制文件

function getfile($blockid)
{
    global $msa_db;
    $sql = "select filename, filedata from blocks where blockid = '$blockid'";
    $query = mysql_query($sql, $msa_db);
    $result['filename'] = mysql_result($query,0,0);
    $result['filedata'] = mysql_result($query,0,1);
    return $result;

}

function download($fileinfo)
{
    $file = base64_decode($fileinfo['filedata']);
    header("Cache-Control: no-cache private");
    header("Content-Description: File Transfer");
    header('Content-disposition: attachment; filename='.$fileinfo['filename']);
    header("Content-Type: application/vnd.ms-excel");
    header("Content-Transfer-Encoding: binary");
    header('Content-Length: '. strlen($file));
    echo $file;
    exit;
}

$fileinfo = getfile($blockid);

download($fileinfo);

刚找到解决办法

http://www.codeproject.com/Articles/831185/CREATE-DOWNLOAD-ZIP-FILE-USING-PHP

    $data = base64_decode($data);

    header("Cache-Control: no-cache private");
    header("Content-Description: File Transfer");
    header("Content-disposition: attachment; filename='".$identifier.".zip'");      
    header("Content-Type: application/octet-stream");
    header("Content-Transfer-Encoding: binary");
    header('Content-Length: '. strlen($data));      
    header("Pragma: no-cache");
    header("Expires: 0");

    ob_clean();
    flush();

    echo $data;