Tengo una página web que tiene el componente de carga de archivos para cargar los tipos de documentos permitidos solo a mi sistema (solo imágenes). No quiero usar la expresión regular para determinar el tipo de archivo y usar la extensión.Determine el tipo de archivo con C#
Háganme saber si existe algún otro medio para determinar los tipos de archivos en C#.
Hay una clase auxiliar en .NET para eso, llamada Ruta de acceso. Lo que necesita es
Path.GetExtension();
Se encuentra en el espacio de nombres System.IO.
También Peter Ritchie tiene razón, debería poder obtener tipos MIME, pero no estoy exactamente seguro sobre la forma correcta de hacerlo. – Robert
Puedo subir un exe fácilmente con una extensión 'jpg' o 'txt'. –
La protección de AFAIK de ejecutables envueltos es un problema de protección de virus/firewall, y no el trabajo del programa en sí.Pero una vez más, no soy un experto en el tema. – Robert
HttpFileCollection hfc = Request.Files;
for (int i = 0; i < hfc.Count - 1; i++)
{
HttpPostedFile hpf = hfc(i);
if (hpf.ContentType == "image/jpeg")
{
//its a jpeg
}
}
Todo lo que ha hecho es comprobar lo que se supone que es el archivo. Podría ser cualquier cosa. Es un buen primer paso, pero algo de inspección de contenido está en orden. –
Vi un ejemplo que estaba en la línea de esto. Debería señalarte en la dirección correcta. Desde el sitio msdn.
string fileName = @"C:\mydir.old\myfile.ext";
string path = @"C:\mydir.old\";
string extension;
extension = Path.GetExtension(fileName);
Console.WriteLine("GetExtension('{0}') returns '{1}'",
fileName, extension);
extension = Path.GetExtension(path);
Console.WriteLine("GetExtension('{0}') returns '{1}'",
path, extension);
// This code produces output similar to the following:
//
// GetExtension('C:\mydir.old\myfile.ext') returns '.ext'
// GetExtension('C:\mydir.old\') returns ''
Parece que está buscando FindMimeFromData. Hay mucha información y código adicional en this question.
Acabo de convertir mi clase VB.NET a C# para detectar tipos de mime. Se identificarán por una mezcla de olfatear los primeros 256 bytes de un archivo (urlmon.dll - es decir, utilizado por Internet Explorer) y un conjunto de tipos conocidos.
También puede usarlo para verificar si el archivo es lo que pretende ser (si la extensión coincide con el tipo).
// check whether or not the uploaded file is an image:
var contentType = MimeTypes.GetContentType(FileUpload1.PostedFile.FileName);
if(contentType.StartsWith("image"))
{
// do something with the image ...
}
Aquí está la clase:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.IO;
public class MimeTypes
{
private static List<string> knownTypes;
private static Dictionary<string, string> mimeTypes;
[DllImport("urlmon.dll", CharSet = CharSet.Auto)]
private static extern UInt32 FindMimeFromData(
UInt32 pBC, [MarshalAs(UnmanagedType.LPStr)]
string pwzUrl, [MarshalAs(UnmanagedType.LPArray)]
byte[] pBuffer, UInt32 cbSize, [MarshalAs(UnmanagedType.LPStr)]
string pwzMimeProposed, UInt32 dwMimeFlags, ref UInt32 ppwzMimeOut, UInt32 dwReserverd
);
public static string GetContentType(string fileName)
{
if (knownTypes == null || mimeTypes == null)
InitializeMimeTypeLists();
string contentType = "";
string extension = System.IO.Path.GetExtension(fileName).Replace(".", "").ToLower();
mimeTypes.TryGetValue(extension, out contentType);
if (string.IsNullOrEmpty(contentType) || knownTypes.Contains(contentType))
{
string headerType = ScanFileForMimeType(fileName);
if (headerType != "application/octet-stream" || string.IsNullOrEmpty(contentType))
contentType = headerType;
}
return contentType;
}
private static string ScanFileForMimeType(string fileName)
{
try
{
byte[] buffer = new byte[256];
using (FileStream fs = new FileStream(fileName, FileMode.Open))
{
int readLength = Convert.ToInt32(Math.Min(256, fs.Length));
fs.Read(buffer, 0, readLength);
}
UInt32 mimeType = default(UInt32);
FindMimeFromData(0, null, buffer, 256, null, 0, ref mimeType, 0);
IntPtr mimeTypePtr = new IntPtr(mimeType);
string mime = Marshal.PtrToStringUni(mimeTypePtr);
Marshal.FreeCoTaskMem(mimeTypePtr);
if (string.IsNullOrEmpty(mime))
mime = "application/octet-stream";
return mime;
} catch (Exception ex)
{
return "application/octet-stream";
}
}
private static void InitializeMimeTypeLists()
{
knownTypes = new string[] {
"text/plain",
"text/html",
"text/xml",
"text/richtext",
"text/scriptlet",
"audio/x-aiff",
"audio/basic",
"audio/mid",
"audio/wav",
"image/gif",
"image/jpeg",
"image/pjpeg",
"image/png",
"image/x-png",
"image/tiff",
"image/bmp",
"image/x-xbitmap",
"image/x-jg",
"image/x-emf",
"image/x-wmf",
"video/avi",
"video/mpeg",
"application/octet-stream",
"application/postscript",
"application/base64",
"application/macbinhex40",
"application/pdf",
"application/xml",
"application/atom+xml",
"application/rss+xml",
"application/x-compressed",
"application/x-zip-compressed",
"application/x-gzip-compressed",
"application/java",
"application/x-msdownload"
}.ToList();
mimeTypes = new Dictionary<string, string>();
mimeTypes.Add("3dm", "x-world/x-3dmf");
mimeTypes.Add("3dmf", "x-world/x-3dmf");
mimeTypes.Add("a", "application/octet-stream");
mimeTypes.Add("aab", "application/x-authorware-bin");
mimeTypes.Add("aam", "application/x-authorware-map");
mimeTypes.Add("aas", "application/x-authorware-seg");
mimeTypes.Add("abc", "text/vnd.abc");
mimeTypes.Add("acgi", "text/html");
mimeTypes.Add("afl", "video/animaflex");
mimeTypes.Add("ai", "application/postscript");
mimeTypes.Add("aif", "audio/aiff");
mimeTypes.Add("aifc", "audio/aiff");
mimeTypes.Add("aiff", "audio/aiff");
mimeTypes.Add("aim", "application/x-aim");
mimeTypes.Add("aip", "text/x-audiosoft-intra");
mimeTypes.Add("ani", "application/x-navi-animation");
mimeTypes.Add("aos", "application/x-nokia-9000-communicator-add-on-software");
mimeTypes.Add("aps", "application/mime");
mimeTypes.Add("arc", "application/octet-stream");
mimeTypes.Add("arj", "application/arj");
mimeTypes.Add("art", "image/x-jg");
mimeTypes.Add("asf", "video/x-ms-asf");
mimeTypes.Add("asm", "text/x-asm");
mimeTypes.Add("asp", "text/asp");
mimeTypes.Add("asx", "application/x-mplayer2");
mimeTypes.Add("au", "audio/basic");
mimeTypes.Add("avi", "video/avi");
mimeTypes.Add("avs", "video/avs-video");
mimeTypes.Add("bcpio", "application/x-bcpio");
mimeTypes.Add("bin", "application/octet-stream");
mimeTypes.Add("bm", "image/bmp");
mimeTypes.Add("bmp", "image/bmp");
mimeTypes.Add("boo", "application/book");
mimeTypes.Add("book", "application/book");
mimeTypes.Add("boz", "application/x-bzip2");
mimeTypes.Add("bsh", "application/x-bsh");
mimeTypes.Add("bz", "application/x-bzip");
mimeTypes.Add("bz2", "application/x-bzip2");
mimeTypes.Add("c", "text/plain");
mimeTypes.Add("c++", "text/plain");
mimeTypes.Add("cat", "application/vnd.ms-pki.seccat");
mimeTypes.Add("cc", "text/plain");
mimeTypes.Add("ccad", "application/clariscad");
mimeTypes.Add("cco", "application/x-cocoa");
mimeTypes.Add("cdf", "application/cdf");
mimeTypes.Add("cer", "application/pkix-cert");
mimeTypes.Add("cha", "application/x-chat");
mimeTypes.Add("chat", "application/x-chat");
mimeTypes.Add("class", "application/java");
mimeTypes.Add("com", "application/octet-stream");
mimeTypes.Add("conf", "text/plain");
mimeTypes.Add("cpio", "application/x-cpio");
mimeTypes.Add("cpp", "text/x-c");
mimeTypes.Add("cpt", "application/x-cpt");
mimeTypes.Add("crl", "application/pkcs-crl");
mimeTypes.Add("css", "text/css");
mimeTypes.Add("def", "text/plain");
mimeTypes.Add("der", "application/x-x509-ca-cert");
mimeTypes.Add("dif", "video/x-dv");
mimeTypes.Add("dir", "application/x-director");
mimeTypes.Add("dl", "video/dl");
mimeTypes.Add("doc", "application/msword");
mimeTypes.Add("dot", "application/msword");
mimeTypes.Add("dp", "application/commonground");
mimeTypes.Add("drw", "application/drafting");
mimeTypes.Add("dump", "application/octet-stream");
mimeTypes.Add("dv", "video/x-dv");
mimeTypes.Add("dvi", "application/x-dvi");
mimeTypes.Add("dwf", "drawing/x-dwf (old)");
mimeTypes.Add("dwg", "application/acad");
mimeTypes.Add("dxf", "application/dxf");
mimeTypes.Add("eps", "application/postscript");
mimeTypes.Add("es", "application/x-esrehber");
mimeTypes.Add("etx", "text/x-setext");
mimeTypes.Add("evy", "application/envoy");
mimeTypes.Add("exe", "application/octet-stream");
mimeTypes.Add("f", "text/plain");
mimeTypes.Add("f90", "text/x-fortran");
mimeTypes.Add("fdf", "application/vnd.fdf");
mimeTypes.Add("fif", "image/fif");
mimeTypes.Add("fli", "video/fli");
mimeTypes.Add("flv", "video/x-flv");
mimeTypes.Add("for", "text/x-fortran");
mimeTypes.Add("fpx", "image/vnd.fpx");
mimeTypes.Add("g", "text/plain");
mimeTypes.Add("g3", "image/g3fax");
mimeTypes.Add("gif", "image/gif");
mimeTypes.Add("gl", "video/gl");
mimeTypes.Add("gsd", "audio/x-gsm");
mimeTypes.Add("gtar", "application/x-gtar");
mimeTypes.Add("gz", "application/x-compressed");
mimeTypes.Add("h", "text/plain");
mimeTypes.Add("help", "application/x-helpfile");
mimeTypes.Add("hgl", "application/vnd.hp-hpgl");
mimeTypes.Add("hh", "text/plain");
mimeTypes.Add("hlp", "application/x-winhelp");
mimeTypes.Add("htc", "text/x-component");
mimeTypes.Add("htm", "text/html");
mimeTypes.Add("html", "text/html");
mimeTypes.Add("htmls", "text/html");
mimeTypes.Add("htt", "text/webviewhtml");
mimeTypes.Add("htx", "text/html");
mimeTypes.Add("ice", "x-conference/x-cooltalk");
mimeTypes.Add("ico", "image/x-icon");
mimeTypes.Add("idc", "text/plain");
mimeTypes.Add("ief", "image/ief");
mimeTypes.Add("iefs", "image/ief");
mimeTypes.Add("iges", "application/iges");
mimeTypes.Add("igs", "application/iges");
mimeTypes.Add("ima", "application/x-ima");
mimeTypes.Add("imap", "application/x-httpd-imap");
mimeTypes.Add("inf", "application/inf");
mimeTypes.Add("ins", "application/x-internett-signup");
mimeTypes.Add("ip", "application/x-ip2");
mimeTypes.Add("isu", "video/x-isvideo");
mimeTypes.Add("it", "audio/it");
mimeTypes.Add("iv", "application/x-inventor");
mimeTypes.Add("ivr", "i-world/i-vrml");
mimeTypes.Add("ivy", "application/x-livescreen");
mimeTypes.Add("jam", "audio/x-jam");
mimeTypes.Add("jav", "text/plain");
mimeTypes.Add("java", "text/plain");
mimeTypes.Add("jcm", "application/x-java-commerce");
mimeTypes.Add("jfif", "image/jpeg");
mimeTypes.Add("jfif-tbnl", "image/jpeg");
mimeTypes.Add("jpe", "image/jpeg");
mimeTypes.Add("jpeg", "image/jpeg");
mimeTypes.Add("jpg", "image/jpeg");
mimeTypes.Add("jps", "image/x-jps");
mimeTypes.Add("js", "application/x-javascript");
mimeTypes.Add("jut", "image/jutvision");
mimeTypes.Add("kar", "audio/midi");
mimeTypes.Add("ksh", "application/x-ksh");
mimeTypes.Add("la", "audio/nspaudio");
mimeTypes.Add("lam", "audio/x-liveaudio");
mimeTypes.Add("latex", "application/x-latex");
mimeTypes.Add("lha", "application/lha");
mimeTypes.Add("lhx", "application/octet-stream");
mimeTypes.Add("list", "text/plain");
mimeTypes.Add("lma", "audio/nspaudio");
mimeTypes.Add("log", "text/plain");
mimeTypes.Add("lsp", "application/x-lisp");
mimeTypes.Add("lst", "text/plain");
mimeTypes.Add("lsx", "text/x-la-asf");
mimeTypes.Add("ltx", "application/x-latex");
mimeTypes.Add("lzh", "application/octet-stream");
mimeTypes.Add("lzx", "application/lzx");
mimeTypes.Add("m", "text/plain");
mimeTypes.Add("m1v", "video/mpeg");
mimeTypes.Add("m2a", "audio/mpeg");
mimeTypes.Add("m2v", "video/mpeg");
mimeTypes.Add("m3u", "audio/x-mpequrl");
mimeTypes.Add("man", "application/x-troff-man");
mimeTypes.Add("map", "application/x-navimap");
mimeTypes.Add("mar", "text/plain");
mimeTypes.Add("mbd", "application/mbedlet");
mimeTypes.Add("mc$", "application/x-magic-cap-package-1.0");
mimeTypes.Add("mcd", "application/mcad");
mimeTypes.Add("mcf", "image/vasa");
mimeTypes.Add("mcp", "application/netmc");
mimeTypes.Add("me", "application/x-troff-me");
mimeTypes.Add("mht", "message/rfc822");
mimeTypes.Add("mhtml", "message/rfc822");
mimeTypes.Add("mid", "audio/midi");
mimeTypes.Add("midi", "audio/midi");
mimeTypes.Add("mif", "application/x-frame");
mimeTypes.Add("mime", "message/rfc822");
mimeTypes.Add("mjf", "audio/x-vnd.audioexplosion.mjuicemediafile");
mimeTypes.Add("mjpg", "video/x-motion-jpeg");
mimeTypes.Add("mm", "application/base64");
mimeTypes.Add("mme", "application/base64");
mimeTypes.Add("mod", "audio/mod");
mimeTypes.Add("moov", "video/quicktime");
mimeTypes.Add("mov", "video/quicktime");
mimeTypes.Add("movie", "video/x-sgi-movie");
mimeTypes.Add("mp2", "audio/mpeg");
mimeTypes.Add("mp3", "audio/mpeg3");
mimeTypes.Add("mpa", "audio/mpeg");
mimeTypes.Add("mpc", "application/x-project");
mimeTypes.Add("mpe", "video/mpeg");
mimeTypes.Add("mpeg", "video/mpeg");
mimeTypes.Add("mpg", "video/mpeg");
mimeTypes.Add("mpga", "audio/mpeg");
mimeTypes.Add("mpp", "application/vnd.ms-project");
mimeTypes.Add("mpt", "application/x-project");
mimeTypes.Add("mpv", "application/x-project");
mimeTypes.Add("mpx", "application/x-project");
mimeTypes.Add("mrc", "application/marc");
mimeTypes.Add("ms", "application/x-troff-ms");
mimeTypes.Add("mv", "video/x-sgi-movie");
mimeTypes.Add("my", "audio/make");
mimeTypes.Add("mzz", "application/x-vnd.audioexplosion.mzz");
mimeTypes.Add("nap", "image/naplps");
mimeTypes.Add("naplps", "image/naplps");
mimeTypes.Add("nc", "application/x-netcdf");
mimeTypes.Add("ncm", "application/vnd.nokia.configuration-message");
mimeTypes.Add("nif", "image/x-niff");
mimeTypes.Add("niff", "image/x-niff");
mimeTypes.Add("nix", "application/x-mix-transfer");
mimeTypes.Add("nsc", "application/x-conference");
mimeTypes.Add("nvd", "application/x-navidoc");
mimeTypes.Add("o", "application/octet-stream");
mimeTypes.Add("oda", "application/oda");
mimeTypes.Add("omc", "application/x-omc");
mimeTypes.Add("omcd", "application/x-omcdatamaker");
mimeTypes.Add("omcr", "application/x-omcregerator");
mimeTypes.Add("p", "text/x-pascal");
mimeTypes.Add("p10", "application/pkcs10");
mimeTypes.Add("p12", "application/pkcs-12");
mimeTypes.Add("p7a", "application/x-pkcs7-signature");
mimeTypes.Add("p7c", "application/pkcs7-mime");
mimeTypes.Add("pas", "text/pascal");
mimeTypes.Add("pbm", "image/x-portable-bitmap");
mimeTypes.Add("pcl", "application/vnd.hp-pcl");
mimeTypes.Add("pct", "image/x-pict");
mimeTypes.Add("pcx", "image/x-pcx");
mimeTypes.Add("pdf", "application/pdf");
mimeTypes.Add("pfunk", "audio/make");
mimeTypes.Add("pgm", "image/x-portable-graymap");
mimeTypes.Add("pic", "image/pict");
mimeTypes.Add("pict", "image/pict");
mimeTypes.Add("pkg", "application/x-newton-compatible-pkg");
mimeTypes.Add("pko", "application/vnd.ms-pki.pko");
mimeTypes.Add("pl", "text/plain");
mimeTypes.Add("plx", "application/x-pixclscript");
mimeTypes.Add("pm", "image/x-xpixmap");
mimeTypes.Add("png", "image/png");
mimeTypes.Add("pnm", "application/x-portable-anymap");
mimeTypes.Add("pot", "application/mspowerpoint");
mimeTypes.Add("pov", "model/x-pov");
mimeTypes.Add("ppa", "application/vnd.ms-powerpoint");
mimeTypes.Add("ppm", "image/x-portable-pixmap");
mimeTypes.Add("pps", "application/mspowerpoint");
mimeTypes.Add("ppt", "application/mspowerpoint");
mimeTypes.Add("ppz", "application/mspowerpoint");
mimeTypes.Add("pre", "application/x-freelance");
mimeTypes.Add("prt", "application/pro_eng");
mimeTypes.Add("ps", "application/postscript");
mimeTypes.Add("psd", "application/octet-stream");
mimeTypes.Add("pvu", "paleovu/x-pv");
mimeTypes.Add("pwz", "application/vnd.ms-powerpoint");
mimeTypes.Add("py", "text/x-script.phyton");
mimeTypes.Add("pyc", "applicaiton/x-bytecode.python");
mimeTypes.Add("qcp", "audio/vnd.qcelp");
mimeTypes.Add("qd3", "x-world/x-3dmf");
mimeTypes.Add("qd3d", "x-world/x-3dmf");
mimeTypes.Add("qif", "image/x-quicktime");
mimeTypes.Add("qt", "video/quicktime");
mimeTypes.Add("qtc", "video/x-qtc");
mimeTypes.Add("qti", "image/x-quicktime");
mimeTypes.Add("qtif", "image/x-quicktime");
mimeTypes.Add("ra", "audio/x-pn-realaudio");
mimeTypes.Add("ram", "audio/x-pn-realaudio");
mimeTypes.Add("ras", "application/x-cmu-raster");
mimeTypes.Add("rast", "image/cmu-raster");
mimeTypes.Add("rexx", "text/x-script.rexx");
mimeTypes.Add("rf", "image/vnd.rn-realflash");
mimeTypes.Add("rgb", "image/x-rgb");
mimeTypes.Add("rm", "application/vnd.rn-realmedia");
mimeTypes.Add("rmi", "audio/mid");
mimeTypes.Add("rmm", "audio/x-pn-realaudio");
mimeTypes.Add("rmp", "audio/x-pn-realaudio");
mimeTypes.Add("rng", "application/ringing-tones");
mimeTypes.Add("rnx", "application/vnd.rn-realplayer");
mimeTypes.Add("roff", "application/x-troff");
mimeTypes.Add("rp", "image/vnd.rn-realpix");
mimeTypes.Add("rpm", "audio/x-pn-realaudio-plugin");
mimeTypes.Add("rt", "text/richtext");
mimeTypes.Add("rtf", "text/richtext");
mimeTypes.Add("rtx", "application/rtf");
mimeTypes.Add("rv", "video/vnd.rn-realvideo");
mimeTypes.Add("s", "text/x-asm");
mimeTypes.Add("s3m", "audio/s3m");
mimeTypes.Add("saveme", "application/octet-stream");
mimeTypes.Add("sbk", "application/x-tbook");
mimeTypes.Add("scm", "application/x-lotusscreencam");
mimeTypes.Add("sdml", "text/plain");
mimeTypes.Add("sdp", "application/sdp");
mimeTypes.Add("sdr", "application/sounder");
mimeTypes.Add("sea", "application/sea");
mimeTypes.Add("set", "application/set");
mimeTypes.Add("sgm", "text/sgml");
mimeTypes.Add("sgml", "text/sgml");
mimeTypes.Add("sh", "application/x-bsh");
mimeTypes.Add("shtml", "text/html");
mimeTypes.Add("sid", "audio/x-psid");
mimeTypes.Add("sit", "application/x-sit");
mimeTypes.Add("skd", "application/x-koan");
mimeTypes.Add("skm", "application/x-koan");
mimeTypes.Add("skp", "application/x-koan");
mimeTypes.Add("skt", "application/x-koan");
mimeTypes.Add("sl", "application/x-seelogo");
mimeTypes.Add("smi", "application/smil");
mimeTypes.Add("smil", "application/smil");
mimeTypes.Add("snd", "audio/basic");
mimeTypes.Add("sol", "application/solids");
mimeTypes.Add("spc", "application/x-pkcs7-certificates");
mimeTypes.Add("spl", "application/futuresplash");
mimeTypes.Add("spr", "application/x-sprite");
mimeTypes.Add("sprite", "application/x-sprite");
mimeTypes.Add("src", "application/x-wais-source");
mimeTypes.Add("ssi", "text/x-server-parsed-html");
mimeTypes.Add("ssm", "application/streamingmedia");
mimeTypes.Add("sst", "application/vnd.ms-pki.certstore");
mimeTypes.Add("step", "application/step");
mimeTypes.Add("stl", "application/sla");
mimeTypes.Add("stp", "application/step");
mimeTypes.Add("sv4cpio", "application/x-sv4cpio");
mimeTypes.Add("sv4crc", "application/x-sv4crc");
mimeTypes.Add("svf", "image/vnd.dwg");
mimeTypes.Add("svr", "application/x-world");
mimeTypes.Add("swf", "application/x-shockwave-flash");
mimeTypes.Add("t", "application/x-troff");
mimeTypes.Add("talk", "text/x-speech");
mimeTypes.Add("tar", "application/x-tar");
mimeTypes.Add("tbk", "application/toolbook");
mimeTypes.Add("tcl", "application/x-tcl");
mimeTypes.Add("tcsh", "text/x-script.tcsh");
mimeTypes.Add("tex", "application/x-tex");
mimeTypes.Add("texi", "application/x-texinfo");
mimeTypes.Add("texinfo", "application/x-texinfo");
mimeTypes.Add("text", "text/plain");
mimeTypes.Add("tgz", "application/x-compressed");
mimeTypes.Add("tif", "image/tiff");
mimeTypes.Add("tr", "application/x-troff");
mimeTypes.Add("tsi", "audio/tsp-audio");
mimeTypes.Add("tsp", "audio/tsplayer");
mimeTypes.Add("tsv", "text/tab-separated-values");
mimeTypes.Add("turbot", "image/florian");
mimeTypes.Add("txt", "text/plain");
mimeTypes.Add("uil", "text/x-uil");
mimeTypes.Add("uni", "text/uri-list");
mimeTypes.Add("unis", "text/uri-list");
mimeTypes.Add("unv", "application/i-deas");
mimeTypes.Add("uri", "text/uri-list");
mimeTypes.Add("uris", "text/uri-list");
mimeTypes.Add("ustar", "application/x-ustar");
mimeTypes.Add("uu", "application/octet-stream");
mimeTypes.Add("vcd", "application/x-cdlink");
mimeTypes.Add("vcs", "text/x-vcalendar");
mimeTypes.Add("vda", "application/vda");
mimeTypes.Add("vdo", "video/vdo");
mimeTypes.Add("vew", "application/groupwise");
mimeTypes.Add("viv", "video/vivo");
mimeTypes.Add("vivo", "video/vivo");
mimeTypes.Add("vmd", "application/vocaltec-media-desc");
mimeTypes.Add("vmf", "application/vocaltec-media-file");
mimeTypes.Add("voc", "audio/voc");
mimeTypes.Add("vos", "video/vosaic");
mimeTypes.Add("vox", "audio/voxware");
mimeTypes.Add("vqe", "audio/x-twinvq-plugin");
mimeTypes.Add("vqf", "audio/x-twinvq");
mimeTypes.Add("vql", "audio/x-twinvq-plugin");
mimeTypes.Add("vrml", "application/x-vrml");
mimeTypes.Add("vrt", "x-world/x-vrt");
mimeTypes.Add("vsd", "application/x-visio");
mimeTypes.Add("vst", "application/x-visio");
mimeTypes.Add("vsw", "application/x-visio");
mimeTypes.Add("w60", "application/wordperfect6.0");
mimeTypes.Add("w61", "application/wordperfect6.1");
mimeTypes.Add("w6w", "application/msword");
mimeTypes.Add("wav", "audio/wav");
mimeTypes.Add("wb1", "application/x-qpro");
mimeTypes.Add("wbmp", "image/vnd.wap.wbmp");
mimeTypes.Add("web", "application/vnd.xara");
mimeTypes.Add("wiz", "application/msword");
mimeTypes.Add("wk1", "application/x-123");
mimeTypes.Add("wmf", "windows/metafile");
mimeTypes.Add("wml", "text/vnd.wap.wml");
mimeTypes.Add("wmlc", "application/vnd.wap.wmlc");
mimeTypes.Add("wmls", "text/vnd.wap.wmlscript");
mimeTypes.Add("wmlsc", "application/vnd.wap.wmlscriptc");
mimeTypes.Add("word", "application/msword");
mimeTypes.Add("wp", "application/wordperfect");
mimeTypes.Add("wp5", "application/wordperfect");
mimeTypes.Add("wp6", "application/wordperfect");
mimeTypes.Add("wpd", "application/wordperfect");
mimeTypes.Add("wq1", "application/x-lotus");
mimeTypes.Add("wri", "application/mswrite");
mimeTypes.Add("wrl", "application/x-world");
mimeTypes.Add("wrz", "model/vrml");
mimeTypes.Add("wsc", "text/scriplet");
mimeTypes.Add("wsrc", "application/x-wais-source");
mimeTypes.Add("wtk", "application/x-wintalk");
mimeTypes.Add("xbm", "image/x-xbitmap");
mimeTypes.Add("xdr", "video/x-amt-demorun");
mimeTypes.Add("xgz", "xgl/drawing");
mimeTypes.Add("xif", "image/vnd.xiff");
mimeTypes.Add("xl", "application/excel");
mimeTypes.Add("xla", "application/excel");
mimeTypes.Add("xlb", "application/excel");
mimeTypes.Add("xlc", "application/excel");
mimeTypes.Add("xld", "application/excel");
mimeTypes.Add("xlk", "application/excel");
mimeTypes.Add("xll", "application/excel");
mimeTypes.Add("xlm", "application/excel");
mimeTypes.Add("xls", "application/excel");
mimeTypes.Add("xlsx", "application/excel");
mimeTypes.Add("xlt", "application/excel");
mimeTypes.Add("xlv", "application/excel");
mimeTypes.Add("xlw", "application/excel");
mimeTypes.Add("xm", "audio/xm");
mimeTypes.Add("xml", "text/xml");
mimeTypes.Add("xmz", "xgl/movie");
mimeTypes.Add("xpix", "application/x-vnd.ls-xpix");
mimeTypes.Add("xpm", "image/x-xpixmap");
mimeTypes.Add("x-png", "image/png");
mimeTypes.Add("xsr", "video/x-amt-showrun");
mimeTypes.Add("xwd", "image/x-xwd");
mimeTypes.Add("xyz", "chemical/x-pdb");
mimeTypes.Add("z", "application/x-compress");
mimeTypes.Add("zip", "application/x-compressed");
mimeTypes.Add("zoo", "application/octet-stream");
mimeTypes.Add("zsh", "text/x-script.zsh");
}
}
Tienes que actualizar esta lista cuando un tipo de MIME es desconocida y no es suficiente para saber que es application/octet-stream. Puede ser suficiente comprobar si una extensión es txt, pero el tipo mime es información binaria, porque eso significa que este archivo no es lo que pretende ser.
Aparte de eso, es realmente más fácil usar un RegularExpressionValidator.
Por ejemplo (sólo JPG imágenes):
<asp:FileUpload ID="FileUpload1" runat="server" /><br />
<br />
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click"
Text="Upload File" /> <br />
<br />
<asp:Label ID="Label1" runat="server"></asp:Label>
<asp:RegularExpressionValidator
id="RegularExpressionValidator1" runat="server"
ErrorMessage="Only jpeg files are allowed!"
ValidationExpression="^(([a-zA-Z]:)|(\\{2}\w+)\$?)(\\(\w[\w].*))
+(.jpg|.JPG|.jpeg|.JPEG)$"
ControlToValidate="FileUpload1"></asp:RegularExpressionValidator>
En CodeBehind:
if (FileUpload1.HasFile)
{
string fileExt =
System.IO.Path.GetExtension(FileUpload1.FileName);
if (fileExt == ".jpeg" || fileExt == ".jpg")
{
//do what you want with this image
}
else
{
Label1.Text = "Only .jpeg files are allowed!";
}
}
¡Esto es excelente!. Una pregunta rápida aquí. Si un archivo exe se guarda como archivo .jpg al cambiar la extensión, qué tan bueno es el enfoque con la expresión regular. –
@YagyaSharma: el enfoque de RegularExpression simplemente comprueba el Nombre de archivo del control FileUpload. Entonces no hay un "control profundo" en absoluto. Pero solo tienes que usar mi clase 'MimeTypes ' en el servidor. 'ScanFileForMimeType' mostrará que no es un tipo de imagen sino una' application/octet-stream'. –
He utilizado el enfoque de tipo MIME para implementar esta funcionalidad. Sin embargo, tan pronto como selecciono el archivo exe del diálogo de selección de archivos, la página se actualiza y aparece el mensaje de error "La página no se puede mostrar". Alguna idea de por qué esto puede estar pasando. Atentamente, Yagya –
puede utilizar Myrmec para identificar el tipo de archivo, esta biblioteca usan la cabeza de bytes del archivo. esta biblioteca está disponible en nuget "Myrmec", y esta es la repo, myrmec también es compatible con el tipo de mimo, puede intentarlo. el código se desea:
// create a sniffer instance.
Sniffer sniffer = new Sniffer();
// populate with mata data.
sniffer.Populate(FileTypes.CommonFileTypes);
// get file head byte, may be 20 bytes enough.
byte[] fileHead = ReadFileHead();
// start match.
List<string> results = sniffer.Match(fileHead);
Usted debe ser capaz de obtener información de la información de tipo de contenido en la solicitud –
me gustaría ser exigente en el número de formatos de imagen que aceptar y usar sólo unos pocos para que sabes que el descompresor se explota gratis. –