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

落爺英雄遲暮 提交于 2019-12-02 15:15:55

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.

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);
        }
    }
}
易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!