Come utilizzare i gestori generici (ASHX) in ASP.NET MVC?

Question

Ho bisogno di un generatore di immagini nella mia applicazione ASP.NET MVC, ma non so se è possibile utilizzare ASHX in ASP.NET MVC.

Se esiste una classe simile a IHttpHandler che eredita IViewDataContainer, allora potrei usare ViewData.Model sul mio ASHX.

Ho letto un post di blog su di esso ma sembra obsoleto dalle informazioni che ho ricevuto nel forum ASP.NET

Qualche idea?

Answer 1

Dovresti essere in grado di restituire l'immagine dall'azione? Vedi qui per di più.

E sì, puoi usare ashx insieme a MVC (dicendogli di ignorare il percorso) - ma non sono sicuro che sia l'approccio migliore se non per riutilizzare il codice esistente.

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Mi dispiace ragazzi, il link è stato rimosso. Succede.

Answer 2

Puoi anche usare questa classe ImageResult per restituire un'immagine.

Non è necessario un gestore per creare una route come:

/ ImageGenerator / {action} / {} ImageID /

e restituisce un ImageResult per la richiesta.

 public class ImageResult : ActionResult
    {
        public string SourceFilename { get; set; }
        public MemoryStream SourceStream { get; set; }
        public string ContentType { get; set; }
        public ImageResult(string sourceFilename)
        {
            SourceFilename = sourceFilename;
            ContentType = FileTypeHelper.GetContentType(SourceFilename);
        }
        public ImageResult(MemoryStream sourceStream, string contentType)
        {
            SourceStream = sourceStream;
            ContentType = contentType;
        }
        public override void ExecuteResult(ControllerContext context)
        {   
            var res = context.HttpContext.Response;
            res.Clear();
            res.Cache.SetCacheability(HttpCacheability.NoCache);
            res.ContentType = ContentType;

            if (SourceStream != null)
            {
                SourceStream.WriteTo(res.OutputStream);

            }
            else
            {
               res.TransmitFile(SourceFilename);
            }

        }


    }

Per utilizzare questo, procedi come segue in un controller e aggiungi una route per esso:

public ImageResult GetImage(int imageId)
{
   // Database fetch of image details
   var imageInfo = repository.Get<ImageInfo>(imageId);
   return new ImageResult(imageInfo.FullFilename);
}

Ho aggiunto anche la classe helper FileType:

 public static class FileTypeHelper
{
    public static string GetContentType(string SourceFileName)
    {
        var extension = Path.GetExtension(SourceFileName).ToLower();
         switch (extension)
        {
            case ".ai": return "application/postscript";
            case ".aif": return "audio/x-aiff";
            case ".aifc": return "audio/x-aiff";
            case ".aiff": return "audio/x-aiff";
            case ".asc": return "text/plain";
            case ".au": return "audio/basic";
            case ".avi": return "video/x-msvideo";
            case ".bcpio": return "application/x-bcpio";
            case ".bin": return "application/octet-stream";
            case ".c": return "text/plain";
            case ".cc": return "text/plain";
            case ".ccad": return "application/clariscad";
            case ".cdf": return "application/x-netcdf";
            case ".class": return "application/octet-stream";
            case ".cpio": return "application/x-cpio";
            case ".cpp": return "text/plain";
            case ".cpt": return "application/mac-compactpro";
            case ".cs": return "text/plain";
            case ".csh": return "application/x-csh";
            case ".css": return "text/css";
            case ".dcr": return "application/x-director";
            case ".dir": return "application/x-director";
            case ".dms": return "application/octet-stream";
            case ".doc": return "application/msword";
            case ".drw": return "application/drafting";
            case ".dvi": return "application/x-dvi";
            case ".dwg": return "application/acad";
            case ".dxf": return "application/dxf";
            case ".dxr": return "application/x-director";
            case ".eps": return "application/postscript";
            case ".etx": return "text/x-setext";
            case ".exe": return "application/octet-stream";
            case ".ez": return "application/andrew-inset";
            case ".f": return "text/plain";
            case ".f90": return "text/plain";
            case ".fli": return "video/x-fli";
            case ".flv": return "video/x-flv";
            case ".gif": return "image/gif";
            case ".gtar": return "application/x-gtar";
            case ".gz": return "application/x-gzip";
            case ".h": return "text/plain";
            case ".hdf": return "application/x-hdf";
            case ".hh": return "text/plain";
            case ".hqx": return "application/mac-binhex40";
            case ".htm": return "text/html";
            case ".html": return "text/html";
            case ".ice": return "x-conference/x-cooltalk";
            case ".ief": return "image/ief";
            case ".iges": return "model/iges";
            case ".igs": return "model/iges";
            case ".ips": return "application/x-ipscript";
            case ".ipx": return "application/x-ipix";
            case ".jpe": return "image/jpeg";
            case ".jpeg": return "image/jpeg";
            case ".jpg": return "image/jpeg";
            case ".js": return "application/x-javascript";
            case ".kar": return "audio/midi";
            case ".latex": return "application/x-latex";
            case ".lha": return "application/octet-stream";
            case ".lsp": return "application/x-lisp";
            case ".lzh": return "application/octet-stream";
            case ".m": return "text/plain";
            case ".man": return "application/x-troff-man";
            case ".me": return "application/x-troff-me";
            case ".mesh": return "model/mesh";
            case ".mid": return "audio/midi";
            case ".midi": return "audio/midi";
            case ".mime": return "www/mime";
            case ".mov": return "video/quicktime";
            case ".movie": return "video/x-sgi-movie";
            case ".mp2": return "audio/mpeg";
            case ".mp3": return "audio/mpeg";
            case ".mpe": return "video/mpeg";
            case ".mpeg": return "video/mpeg";
            case ".mpg": return "video/mpeg";
            case ".mpga": return "audio/mpeg";
            case ".ms": return "application/x-troff-ms";
            case ".msh": return "model/mesh";
            case ".nc": return "application/x-netcdf";
            case ".oda": return "application/oda";
            case ".pbm": return "image/x-portable-bitmap";
            case ".pdb": return "chemical/x-pdb";
            case ".pdf": return "application/pdf";
            case ".pgm": return "image/x-portable-graymap";
            case ".pgn": return "application/x-chess-pgn";
            case ".png": return "image/png";
            case ".pnm": return "image/x-portable-anymap";
            case ".pot": return "application/mspowerpoint";
            case ".ppm": return "image/x-portable-pixmap";
            case ".pps": return "application/mspowerpoint";
            case ".ppt": return "application/mspowerpoint";
            case ".ppz": return "application/mspowerpoint";
            case ".pre": return "application/x-freelance";
            case ".prt": return "application/pro_eng";
            case ".ps": return "application/postscript";
            case ".qt": return "video/quicktime";
            case ".ra": return "audio/x-realaudio";
            case ".ram": return "audio/x-pn-realaudio";
            case ".ras": return "image/cmu-raster";
            case ".rgb": return "image/x-rgb";
            case ".rm": return "audio/x-pn-realaudio";
            case ".roff": return "application/x-troff";
            case ".rpm": return "audio/x-pn-realaudio-plugin";
            case ".rtf": return "text/rtf";
            case ".rtx": return "text/richtext";
            case ".scm": return "application/x-lotusscreencam";
            case ".set": return "application/set";
            case ".sgm": return "text/sgml";
            case ".sgml": return "text/sgml";
            case ".sh": return "application/x-sh";
            case ".shar": return "application/x-shar";
            case ".silo": return "model/mesh";
            case ".sit": return "application/x-stuffit";
            case ".skd": return "application/x-koan";
            case ".skm": return "application/x-koan";
            case ".skp": return "application/x-koan";
            case ".skt": return "application/x-koan";
            case ".smi": return "application/smil";
            case ".smil": return "application/smil";
            case ".snd": return "audio/basic";
            case ".sol": return "application/solids";
            case ".spl": return "application/x-futuresplash";
            case ".src": return "application/x-wais-source";
            case ".step": return "application/STEP";
            case ".stl": return "application/SLA";
            case ".stp": return "application/STEP";
            case ".sv4cpio": return "application/x-sv4cpio";
            case ".sv4crc": return "application/x-sv4crc";
            case ".swf": return "application/x-shockwave-flash";
            case ".t": return "application/x-troff";
            case ".tar": return "application/x-tar";
            case ".tcl": return "application/x-tcl";
            case ".tex": return "application/x-tex";
            case ".tif": return "image/tiff";
            case ".tiff": return "image/tiff";
            case ".tr": return "application/x-troff";
            case ".tsi": return "audio/TSP-audio";
            case ".tsp": return "application/dsptype";
            case ".tsv": return "text/tab-separated-values";
            case ".txt": return "text/plain";
            case ".unv": return "application/i-deas";
            case ".ustar": return "application/x-ustar";
            case ".vcd": return "application/x-cdlink";
            case ".vda": return "application/vda";
            case ".vrml": return "model/vrml";
            case ".wav": return "audio/x-wav";
            case ".wrl": return "model/vrml";
            case ".xbm": return "image/x-xbitmap";
            case ".xlc": return "application/vnd.ms-excel";
            case ".xll": return "application/vnd.ms-excel";
            case ".xlm": return "application/vnd.ms-excel";
            case ".xls": return "application/vnd.ms-excel";
            case ".xlw": return "application/vnd.ms-excel";
            case ".xml": return "text/xml";
            case ".xpm": return "image/x-xpixmap";
            case ".xwd": return "image/x-xwindowdump";
            case ".xyz": return "chemical/x-pdb";
            case ".zip": return "application/zip";
            default: return string.Format("application/{0}", extension);
        }
    }
}