How to use Generic Handlers (ASHX) in ASP.NET MVC? How to use Generic Handlers (ASHX) in ASP.NET MVC? asp.net asp.net

How to use Generic Handlers (ASHX) in ASP.NET MVC?


You can also use this ImageResult class to return an image.

No need for a handler just create a route such as:

/ImageGenerator/{action}/{imageid}/

and return an ImageResult for the request.

 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);            }        }    }

To use this do the following in a controller and add a route for it:

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

Have added the FileType helper class too:

 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);        }    }}


You should just be able to return the image from the action? See here for more.

And yes, you can use ashx alongside MVC (by telling it to ignore the route) - but I'm not sure that is the best approach unless it is to re-use existing code.


Sorry guys, the link has been removed. It happens.