如何从文件扩展名中获得MIME类型?
当前回答
Bryan Denny上面的帖子不适合我，因为不是所有的扩展在注册表中都有一个“内容类型”子键。我不得不调整代码如下:
private string GetMimeType(string sFileName)
{
// Get file extension and if it is empty, return unknown
string sExt = Path.GetExtension(sFileName);
if (string.IsNullOrEmpty(sExt)) return "Unknown file type";
// Default type is "EXT File"
string mimeType = string.Format("{0} File", sExt.ToUpper().Replace(".", ""));
// Open the registry key for the extension under HKEY_CLASSES_ROOT and return default if it doesn't exist
Microsoft.Win32.RegistryKey regKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(sExt);
if (regKey == null) return mimeType;
// Get the "(Default)" value and re-open the key for that value
string sSubType = regKey.GetValue("").ToString();
regKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(sSubType);
// If it exists, get the "(Default)" value of the new key
if (regKey?.GetValue("") != null) mimeType = regKey.GetValue("").ToString();
// Return the value
return mimeType;
}
现在它可以为我所有注册的文件类型和未注册的或通用的文件类型(如JPG等)。
其他回答
您可以在注册表中找到这些信息。例如，.pdf文件的MIME类型可以在键HKEY_CLASSES_ROOT\.pdf中找到，在值"Content type "中:
string mimeType = Registry.GetValue(@"HKEY_CLASSES_ROOT\.pdf", "Content Type", null) as string;
我喜欢Samuel Neff所做的工作，但不喜欢每次创建字典的想法和开销。
我把它重组成一个开关案例。是的，你不能迭代它，但在我的情况下，我只使用它来快速查找一个值。特别是因为它是在web服务中完成的，所以我最不希望的就是在应用程序准备其结构时产生大量开销。编译器会把这个转换成散列查找，所以会非常快。
public static string GetMimeType(string extension)
{
if (extension == null)
throw new ArgumentNullException("extension");
if (extension.StartsWith("."))
extension = extension.Substring(1);
switch (extension.ToLower())
{
#region Big freaking list of mime types
case "323": return "text/h323";
case "3g2": return "video/3gpp2";
case "3gp": return "video/3gpp";
case "3gp2": return "video/3gpp2";
case "3gpp": return "video/3gpp";
case "7z": return "application/x-7z-compressed";
case "aa": return "audio/audible";
case "aac": return "audio/aac";
case "aaf": return "application/octet-stream";
case "aax": return "audio/vnd.audible.aax";
case "ac3": return "audio/ac3";
case "aca": return "application/octet-stream";
case "accda": return "application/msaccess.addin";
case "accdb": return "application/msaccess";
case "accdc": return "application/msaccess.cab";
case "accde": return "application/msaccess";
case "accdr": return "application/msaccess.runtime";
case "accdt": return "application/msaccess";
case "accdw": return "application/msaccess.webapplication";
case "accft": return "application/msaccess.ftemplate";
case "acx": return "application/internet-property-stream";
case "addin": return "text/xml";
case "ade": return "application/msaccess";
case "adobebridge": return "application/x-bridge-url";
case "adp": return "application/msaccess";
case "adt": return "audio/vnd.dlna.adts";
case "adts": return "audio/aac";
case "afm": return "application/octet-stream";
case "ai": return "application/postscript";
case "aif": return "audio/x-aiff";
case "aifc": return "audio/aiff";
case "aiff": return "audio/aiff";
case "air": return "application/vnd.adobe.air-application-installer-package+zip";
case "amc": return "application/x-mpeg";
case "application": return "application/x-ms-application";
case "art": return "image/x-jg";
case "asa": return "application/xml";
case "asax": return "application/xml";
case "ascx": return "application/xml";
case "asd": return "application/octet-stream";
case "asf": return "video/x-ms-asf";
case "ashx": return "application/xml";
case "asi": return "application/octet-stream";
case "asm": return "text/plain";
case "asmx": return "application/xml";
case "aspx": return "application/xml";
case "asr": return "video/x-ms-asf";
case "asx": return "video/x-ms-asf";
case "atom": return "application/atom+xml";
case "au": return "audio/basic";
case "avi": return "video/x-msvideo";
case "axs": return "application/olescript";
case "bas": return "text/plain";
case "bcpio": return "application/x-bcpio";
case "bin": return "application/octet-stream";
case "bmp": return "image/bmp";
case "c": return "text/plain";
case "cab": return "application/octet-stream";
case "caf": return "audio/x-caf";
case "calx": return "application/vnd.ms-office.calx";
case "cat": return "application/vnd.ms-pki.seccat";
case "cc": return "text/plain";
case "cd": return "text/plain";
case "cdda": return "audio/aiff";
case "cdf": return "application/x-cdf";
case "cer": return "application/x-x509-ca-cert";
case "chm": return "application/octet-stream";
case "class": return "application/x-java-applet";
case "clp": return "application/x-msclip";
case "cmx": return "image/x-cmx";
case "cnf": return "text/plain";
case "cod": return "image/cis-cod";
case "config": return "application/xml";
case "contact": return "text/x-ms-contact";
case "coverage": return "application/xml";
case "cpio": return "application/x-cpio";
case "cpp": return "text/plain";
case "crd": return "application/x-mscardfile";
case "crl": return "application/pkix-crl";
case "crt": return "application/x-x509-ca-cert";
case "cs": return "text/plain";
case "csdproj": return "text/plain";
case "csh": return "application/x-csh";
case "csproj": return "text/plain";
case "css": return "text/css";
case "csv": return "text/csv";
case "cur": return "application/octet-stream";
case "cxx": return "text/plain";
case "dat": return "application/octet-stream";
case "datasource": return "application/xml";
case "dbproj": return "text/plain";
case "dcr": return "application/x-director";
case "def": return "text/plain";
case "deploy": return "application/octet-stream";
case "der": return "application/x-x509-ca-cert";
case "dgml": return "application/xml";
case "dib": return "image/bmp";
case "dif": return "video/x-dv";
case "dir": return "application/x-director";
case "disco": return "text/xml";
case "dll": return "application/x-msdownload";
case "dll.config": return "text/xml";
case "dlm": return "text/dlm";
case "doc": return "application/msword";
case "docm": return "application/vnd.ms-word.document.macroenabled.12";
case "docx": return "application/vnd.openxmlformats-officedocument.wordprocessingml.document";
case "dot": return "application/msword";
case "dotm": return "application/vnd.ms-word.template.macroenabled.12";
case "dotx": return "application/vnd.openxmlformats-officedocument.wordprocessingml.template";
case "dsp": return "application/octet-stream";
case "dsw": return "text/plain";
case "dtd": return "text/xml";
case "dtsconfig": return "text/xml";
case "dv": return "video/x-dv";
case "dvi": return "application/x-dvi";
case "dwf": return "drawing/x-dwf";
case "dwp": return "application/octet-stream";
case "dxr": return "application/x-director";
case "eml": return "message/rfc822";
case "emz": return "application/octet-stream";
case "eot": return "application/octet-stream";
case "eps": return "application/postscript";
case "etl": return "application/etl";
case "etx": return "text/x-setext";
case "evy": return "application/envoy";
case "exe": return "application/octet-stream";
case "exe.config": return "text/xml";
case "fdf": return "application/vnd.fdf";
case "fif": return "application/fractals";
case "filters": return "application/xml";
case "fla": return "application/octet-stream";
case "flr": return "x-world/x-vrml";
case "flv": return "video/x-flv";
case "fsscript": return "application/fsharp-script";
case "fsx": return "application/fsharp-script";
case "generictest": return "application/xml";
case "gif": return "image/gif";
case "group": return "text/x-ms-group";
case "gsm": return "audio/x-gsm";
case "gtar": return "application/x-gtar";
case "gz": return "application/x-gzip";
case "h": return "text/plain";
case "hdf": return "application/x-hdf";
case "hdml": return "text/x-hdml";
case "hhc": return "application/x-oleobject";
case "hhk": return "application/octet-stream";
case "hhp": return "application/octet-stream";
case "hlp": return "application/winhlp";
case "hpp": return "text/plain";
case "hqx": return "application/mac-binhex40";
case "hta": return "application/hta";
case "htc": return "text/x-component";
case "htm": return "text/html";
case "html": return "text/html";
case "htt": return "text/webviewhtml";
case "hxa": return "application/xml";
case "hxc": return "application/xml";
case "hxd": return "application/octet-stream";
case "hxe": return "application/xml";
case "hxf": return "application/xml";
case "hxh": return "application/octet-stream";
case "hxi": return "application/octet-stream";
case "hxk": return "application/xml";
case "hxq": return "application/octet-stream";
case "hxr": return "application/octet-stream";
case "hxs": return "application/octet-stream";
case "hxt": return "text/html";
case "hxv": return "application/xml";
case "hxw": return "application/octet-stream";
case "hxx": return "text/plain";
case "i": return "text/plain";
case "ico": return "image/x-icon";
case "ics": return "application/octet-stream";
case "idl": return "text/plain";
case "ief": return "image/ief";
case "iii": return "application/x-iphone";
case "inc": return "text/plain";
case "inf": return "application/octet-stream";
case "inl": return "text/plain";
case "ins": return "application/x-internet-signup";
case "ipa": return "application/x-itunes-ipa";
case "ipg": return "application/x-itunes-ipg";
case "ipproj": return "text/plain";
case "ipsw": return "application/x-itunes-ipsw";
case "iqy": return "text/x-ms-iqy";
case "isp": return "application/x-internet-signup";
case "ite": return "application/x-itunes-ite";
case "itlp": return "application/x-itunes-itlp";
case "itms": return "application/x-itunes-itms";
case "itpc": return "application/x-itunes-itpc";
case "ivf": return "video/x-ivf";
case "jar": return "application/java-archive";
case "java": return "application/octet-stream";
case "jck": return "application/liquidmotion";
case "jcz": return "application/liquidmotion";
case "jfif": return "image/pjpeg";
case "jnlp": return "application/x-java-jnlp-file";
case "jpb": return "application/octet-stream";
case "jpe": return "image/jpeg";
case "jpeg": return "image/jpeg";
case "jpg": return "image/jpeg";
case "js": return "application/x-javascript";
case "jsx": return "text/jscript";
case "jsxbin": return "text/plain";
case "latex": return "application/x-latex";
case "library-ms": return "application/windows-library+xml";
case "lit": return "application/x-ms-reader";
case "loadtest": return "application/xml";
case "lpk": return "application/octet-stream";
case "lsf": return "video/x-la-asf";
case "lst": return "text/plain";
case "lsx": return "video/x-la-asf";
case "lzh": return "application/octet-stream";
case "m13": return "application/x-msmediaview";
case "m14": return "application/x-msmediaview";
case "m1v": return "video/mpeg";
case "m2t": return "video/vnd.dlna.mpeg-tts";
case "m2ts": return "video/vnd.dlna.mpeg-tts";
case "m2v": return "video/mpeg";
case "m3u": return "audio/x-mpegurl";
case "m3u8": return "audio/x-mpegurl";
case "m4a": return "audio/m4a";
case "m4b": return "audio/m4b";
case "m4p": return "audio/m4p";
case "m4r": return "audio/x-m4r";
case "m4v": return "video/x-m4v";
case "mac": return "image/x-macpaint";
case "mak": return "text/plain";
case "man": return "application/x-troff-man";
case "manifest": return "application/x-ms-manifest";
case "map": return "text/plain";
case "master": return "application/xml";
case "mda": return "application/msaccess";
case "mdb": return "application/x-msaccess";
case "mde": return "application/msaccess";
case "mdp": return "application/octet-stream";
case "me": return "application/x-troff-me";
case "mfp": return "application/x-shockwave-flash";
case "mht": return "message/rfc822";
case "mhtml": return "message/rfc822";
case "mid": return "audio/mid";
case "midi": return "audio/mid";
case "mix": return "application/octet-stream";
case "mk": return "text/plain";
case "mmf": return "application/x-smaf";
case "mno": return "text/xml";
case "mny": return "application/x-msmoney";
case "mod": return "video/mpeg";
case "mov": return "video/quicktime";
case "movie": return "video/x-sgi-movie";
case "mp2": return "video/mpeg";
case "mp2v": return "video/mpeg";
case "mp3": return "audio/mpeg";
case "mp4": return "video/mp4";
case "mp4v": return "video/mp4";
case "mpa": return "video/mpeg";
case "mpe": return "video/mpeg";
case "mpeg": return "video/mpeg";
case "mpf": return "application/vnd.ms-mediapackage";
case "mpg": return "video/mpeg";
case "mpp": return "application/vnd.ms-project";
case "mpv2": return "video/mpeg";
case "mqv": return "video/quicktime";
case "ms": return "application/x-troff-ms";
case "msi": return "application/octet-stream";
case "mso": return "application/octet-stream";
case "mts": return "video/vnd.dlna.mpeg-tts";
case "mtx": return "application/xml";
case "mvb": return "application/x-msmediaview";
case "mvc": return "application/x-miva-compiled";
case "mxp": return "application/x-mmxp";
case "nc": return "application/x-netcdf";
case "nsc": return "video/x-ms-asf";
case "nws": return "message/rfc822";
case "ocx": return "application/octet-stream";
case "oda": return "application/oda";
case "odc": return "text/x-ms-odc";
case "odh": return "text/plain";
case "odl": return "text/plain";
case "odp": return "application/vnd.oasis.opendocument.presentation";
case "ods": return "application/oleobject";
case "odt": return "application/vnd.oasis.opendocument.text";
case "one": return "application/onenote";
case "onea": return "application/onenote";
case "onepkg": return "application/onenote";
case "onetmp": return "application/onenote";
case "onetoc": return "application/onenote";
case "onetoc2": return "application/onenote";
case "orderedtest": return "application/xml";
case "osdx": return "application/opensearchdescription+xml";
case "p10": return "application/pkcs10";
case "p12": return "application/x-pkcs12";
case "p7b": return "application/x-pkcs7-certificates";
case "p7c": return "application/pkcs7-mime";
case "p7m": return "application/pkcs7-mime";
case "p7r": return "application/x-pkcs7-certreqresp";
case "p7s": return "application/pkcs7-signature";
case "pbm": return "image/x-portable-bitmap";
case "pcast": return "application/x-podcast";
case "pct": return "image/pict";
case "pcx": return "application/octet-stream";
case "pcz": return "application/octet-stream";
case "pdf": return "application/pdf";
case "pfb": return "application/octet-stream";
case "pfm": return "application/octet-stream";
case "pfx": return "application/x-pkcs12";
case "pgm": return "image/x-portable-graymap";
case "pic": return "image/pict";
case "pict": return "image/pict";
case "pkgdef": return "text/plain";
case "pkgundef": return "text/plain";
case "pko": return "application/vnd.ms-pki.pko";
case "pls": return "audio/scpls";
case "pma": return "application/x-perfmon";
case "pmc": return "application/x-perfmon";
case "pml": return "application/x-perfmon";
case "pmr": return "application/x-perfmon";
case "pmw": return "application/x-perfmon";
case "png": return "image/png";
case "pnm": return "image/x-portable-anymap";
case "pnt": return "image/x-macpaint";
case "pntg": return "image/x-macpaint";
case "pnz": return "image/png";
case "pot": return "application/vnd.ms-powerpoint";
case "potm": return "application/vnd.ms-powerpoint.template.macroenabled.12";
case "potx": return "application/vnd.openxmlformats-officedocument.presentationml.template";
case "ppa": return "application/vnd.ms-powerpoint";
case "ppam": return "application/vnd.ms-powerpoint.addin.macroenabled.12";
case "ppm": return "image/x-portable-pixmap";
case "pps": return "application/vnd.ms-powerpoint";
case "ppsm": return "application/vnd.ms-powerpoint.slideshow.macroenabled.12";
case "ppsx": return "application/vnd.openxmlformats-officedocument.presentationml.slideshow";
case "ppt": return "application/vnd.ms-powerpoint";
case "pptm": return "application/vnd.ms-powerpoint.presentation.macroenabled.12";
case "pptx": return "application/vnd.openxmlformats-officedocument.presentationml.presentation";
case "prf": return "application/pics-rules";
case "prm": return "application/octet-stream";
case "prx": return "application/octet-stream";
case "ps": return "application/postscript";
case "psc1": return "application/powershell";
case "psd": return "application/octet-stream";
case "psess": return "application/xml";
case "psm": return "application/octet-stream";
case "psp": return "application/octet-stream";
case "pub": return "application/x-mspublisher";
case "pwz": return "application/vnd.ms-powerpoint";
case "qht": return "text/x-html-insertion";
case "qhtm": return "text/x-html-insertion";
case "qt": return "video/quicktime";
case "qti": return "image/x-quicktime";
case "qtif": return "image/x-quicktime";
case "qtl": return "application/x-quicktimeplayer";
case "qxd": return "application/octet-stream";
case "ra": return "audio/x-pn-realaudio";
case "ram": return "audio/x-pn-realaudio";
case "rar": return "application/octet-stream";
case "ras": return "image/x-cmu-raster";
case "rat": return "application/rat-file";
case "rc": return "text/plain";
case "rc2": return "text/plain";
case "rct": return "text/plain";
case "rdlc": return "application/xml";
case "resx": return "application/xml";
case "rf": return "image/vnd.rn-realflash";
case "rgb": return "image/x-rgb";
case "rgs": return "text/plain";
case "rm": return "application/vnd.rn-realmedia";
case "rmi": return "audio/mid";
case "rmp": return "application/vnd.rn-rn_music_package";
case "roff": return "application/x-troff";
case "rpm": return "audio/x-pn-realaudio-plugin";
case "rqy": return "text/x-ms-rqy";
case "rtf": return "application/rtf";
case "rtx": return "text/richtext";
case "ruleset": return "application/xml";
case "s": return "text/plain";
case "safariextz": return "application/x-safari-safariextz";
case "scd": return "application/x-msschedule";
case "sct": return "text/scriptlet";
case "sd2": return "audio/x-sd2";
case "sdp": return "application/sdp";
case "sea": return "application/octet-stream";
case "searchconnector-ms": return "application/windows-search-connector+xml";
case "setpay": return "application/set-payment-initiation";
case "setreg": return "application/set-registration-initiation";
case "settings": return "application/xml";
case "sgimb": return "application/x-sgimb";
case "sgml": return "text/sgml";
case "sh": return "application/x-sh";
case "shar": return "application/x-shar";
case "shtml": return "text/html";
case "sit": return "application/x-stuffit";
case "sitemap": return "application/xml";
case "skin": return "application/xml";
case "sldm": return "application/vnd.ms-powerpoint.slide.macroenabled.12";
case "sldx": return "application/vnd.openxmlformats-officedocument.presentationml.slide";
case "slk": return "application/vnd.ms-excel";
case "sln": return "text/plain";
case "slupkg-ms": return "application/x-ms-license";
case "smd": return "audio/x-smd";
case "smi": return "application/octet-stream";
case "smx": return "audio/x-smd";
case "smz": return "audio/x-smd";
case "snd": return "audio/basic";
case "snippet": return "application/xml";
case "snp": return "application/octet-stream";
case "sol": return "text/plain";
case "sor": return "text/plain";
case "spc": return "application/x-pkcs7-certificates";
case "spl": return "application/futuresplash";
case "src": return "application/x-wais-source";
case "srf": return "text/plain";
case "ssisdeploymentmanifest": return "text/xml";
case "ssm": return "application/streamingmedia";
case "sst": return "application/vnd.ms-pki.certstore";
case "stl": return "application/vnd.ms-pki.stl";
case "sv4cpio": return "application/x-sv4cpio";
case "sv4crc": return "application/x-sv4crc";
case "svc": return "application/xml";
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 "testrunconfig": return "application/xml";
case "testsettings": return "application/xml";
case "tex": return "application/x-tex";
case "texi": return "application/x-texinfo";
case "texinfo": return "application/x-texinfo";
case "tgz": return "application/x-compressed";
case "thmx": return "application/vnd.ms-officetheme";
case "thn": return "application/octet-stream";
case "tif": return "image/tiff";
case "tiff": return "image/tiff";
case "tlh": return "text/plain";
case "tli": return "text/plain";
case "toc": return "application/octet-stream";
case "tr": return "application/x-troff";
case "trm": return "application/x-msterminal";
case "trx": return "application/xml";
case "ts": return "video/vnd.dlna.mpeg-tts";
case "tsv": return "text/tab-separated-values";
case "ttf": return "application/octet-stream";
case "tts": return "video/vnd.dlna.mpeg-tts";
case "txt": return "text/plain";
case "u32": return "application/octet-stream";
case "uls": return "text/iuls";
case "user": return "text/plain";
case "ustar": return "application/x-ustar";
case "vb": return "text/plain";
case "vbdproj": return "text/plain";
case "vbk": return "video/mpeg";
case "vbproj": return "text/plain";
case "vbs": return "text/vbscript";
case "vcf": return "text/x-vcard";
case "vcproj": return "application/xml";
case "vcs": return "text/plain";
case "vcxproj": return "application/xml";
case "vddproj": return "text/plain";
case "vdp": return "text/plain";
case "vdproj": return "text/plain";
case "vdx": return "application/vnd.ms-visio.viewer";
case "vml": return "text/xml";
case "vscontent": return "application/xml";
case "vsct": return "text/xml";
case "vsd": return "application/vnd.visio";
case "vsi": return "application/ms-vsi";
case "vsix": return "application/vsix";
case "vsixlangpack": return "text/xml";
case "vsixmanifest": return "text/xml";
case "vsmdi": return "application/xml";
case "vspscc": return "text/plain";
case "vss": return "application/vnd.visio";
case "vsscc": return "text/plain";
case "vssettings": return "text/xml";
case "vssscc": return "text/plain";
case "vst": return "application/vnd.visio";
case "vstemplate": return "text/xml";
case "vsto": return "application/x-ms-vsto";
case "vsw": return "application/vnd.visio";
case "vsx": return "application/vnd.visio";
case "vtx": return "application/vnd.visio";
case "wav": return "audio/wav";
case "wave": return "audio/wav";
case "wax": return "audio/x-ms-wax";
case "wbk": return "application/msword";
case "wbmp": return "image/vnd.wap.wbmp";
case "wcm": return "application/vnd.ms-works";
case "wdb": return "application/vnd.ms-works";
case "wdp": return "image/vnd.ms-photo";
case "webarchive": return "application/x-safari-webarchive";
case "webtest": return "application/xml";
case "wiq": return "application/xml";
case "wiz": return "application/msword";
case "wks": return "application/vnd.ms-works";
case "wlmp": return "application/wlmoviemaker";
case "wlpginstall": return "application/x-wlpg-detect";
case "wlpginstall3": return "application/x-wlpg3-detect";
case "wm": return "video/x-ms-wm";
case "wma": return "audio/x-ms-wma";
case "wmd": return "application/x-ms-wmd";
case "wmf": return "application/x-msmetafile";
case "wml": return "text/vnd.wap.wml";
case "wmlc": return "application/vnd.wap.wmlc";
case "wmls": return "text/vnd.wap.wmlscript";
case "wmlsc": return "application/vnd.wap.wmlscriptc";
case "wmp": return "video/x-ms-wmp";
case "wmv": return "video/x-ms-wmv";
case "wmx": return "video/x-ms-wmx";
case "wmz": return "application/x-ms-wmz";
case "wpl": return "application/vnd.ms-wpl";
case "wps": return "application/vnd.ms-works";
case "wri": return "application/x-mswrite";
case "wrl": return "x-world/x-vrml";
case "wrz": return "x-world/x-vrml";
case "wsc": return "text/scriptlet";
case "wsdl": return "text/xml";
case "wvx": return "video/x-ms-wvx";
case "x": return "application/directx";
case "xaf": return "x-world/x-vrml";
case "xaml": return "application/xaml+xml";
case "xap": return "application/x-silverlight-app";
case "xbap": return "application/x-ms-xbap";
case "xbm": return "image/x-xbitmap";
case "xdr": return "text/plain";
case "xht": return "application/xhtml+xml";
case "xhtml": return "application/xhtml+xml";
case "xla": return "application/vnd.ms-excel";
case "xlam": return "application/vnd.ms-excel.addin.macroenabled.12";
case "xlc": return "application/vnd.ms-excel";
case "xld": return "application/vnd.ms-excel";
case "xlk": 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 "xlsb": return "application/vnd.ms-excel.sheet.binary.macroenabled.12";
case "xlsm": return "application/vnd.ms-excel.sheet.macroenabled.12";
case "xlsx": return "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
case "xlt": return "application/vnd.ms-excel";
case "xltm": return "application/vnd.ms-excel.template.macroenabled.12";
case "xltx": return "application/vnd.openxmlformats-officedocument.spreadsheetml.template";
case "xlw": return "application/vnd.ms-excel";
case "xml": return "text/xml";
case "xmta": return "application/xml";
case "xof": return "x-world/x-vrml";
case "xoml": return "text/plain";
case "xpm": return "image/x-xpixmap";
case "xps": return "application/vnd.ms-xpsdocument";
case "xrm-ms": return "text/xml";
case "xsc": return "application/xml";
case "xsd": return "text/xml";
case "xsf": return "text/xml";
case "xsl": return "text/xml";
case "xslt": return "text/xml";
case "xsn": return "application/octet-stream";
case "xss": return "application/xml";
case "xtp": return "application/octet-stream";
case "xwd": return "image/x-xwindowdump";
case "z": return "application/x-compress";
case "zip": return "application/x-zip-compressed";
#endregion
default: return "application/octet-stream";
}
}
. net框架提供了获取mime类型的内置方法。不需要编写自定义代码。
string mimeType = System.Web.MimeMapping.GetMimeMapping(fileName);
您可以使用Apache的httpd提供的表。将其映射到函数、字典、列表等应该是很简单的。
另外，正如这里所看到的，extension->mime类型不一定是函数。每个文件扩展名可能有多种常见的MIME类型，所以你应该看看你的应用程序的需求，看看你为什么关心MIME类型，你想用它们“做什么”等等。您可以使用文件扩展名来确定相同的行为吗?您是否也需要读取文件的前几个字节来确定其MIME类型?
这个helper类返回任何文件名的mime类型(内容类型)、描述和图标:
using Microsoft.Win32;
using System;
using System.Drawing;
using System.IO;
using System.Runtime.InteropServices;
public static class Helper
{
[DllImport("shell32.dll", CharSet = CharSet.Auto)]
private static extern int ExtractIconEx(string lpszFile, int nIconIndex, IntPtr[] phIconLarge, IntPtr[] phIconSmall, int nIcons);
[DllImport("user32.dll", SetLastError = true)]
private static extern int DestroyIcon(IntPtr hIcon);
public static string GetFileContentType(string fileName)
{
if (fileName == null)
{
throw new ArgumentNullException("fileName");
}
RegistryKey registryKey = null;
try
{
FileInfo fileInfo = new FileInfo(fileName);
if (string.IsNullOrEmpty(fileInfo.Extension))
{
return string.Empty;
}
string extension = fileInfo.Extension.ToLowerInvariant();
registryKey = Registry.ClassesRoot.OpenSubKey(extension);
if (registryKey == null)
{
return string.Empty;
}
object contentTypeObject = registryKey.GetValue("Content Type");
if (!(contentTypeObject is string))
{
return string.Empty;
}
string contentType = (string)contentTypeObject;
return contentType;
}
catch (Exception)
{
return null;
}
finally
{
if (registryKey != null)
{
registryKey.Close();
}
}
}
public static string GetFileDescription(string fileName)
{
if (fileName == null)
{
throw new ArgumentNullException("fileName");
}
RegistryKey registryKey1 = null;
RegistryKey registryKey2 = null;
try
{
FileInfo fileInfo = new FileInfo(fileName);
if (string.IsNullOrEmpty(fileInfo.Extension))
{
return string.Empty;
}
string extension = fileInfo.Extension.ToLowerInvariant();
registryKey1 = Registry.ClassesRoot.OpenSubKey(extension);
if (registryKey1 == null)
{
return string.Empty;
}
object extensionDefaultObject = registryKey1.GetValue(null);
if (!(extensionDefaultObject is string))
{
return string.Empty;
}
string extensionDefaultValue = (string)extensionDefaultObject;
registryKey2 = Registry.ClassesRoot.OpenSubKey(extensionDefaultValue);
if (registryKey2 == null)
{
return string.Empty;
}
object fileDescriptionObject = registryKey2.GetValue(null);
if (!(fileDescriptionObject is string))
{
return string.Empty;
}
string fileDescription = (string)fileDescriptionObject;
return fileDescription;
}
catch (Exception)
{
return null;
}
finally
{
if (registryKey2 != null)
{
registryKey2.Close();
}
if (registryKey1 != null)
{
registryKey1.Close();
}
}
}
public static void GetFileIcons(string fileName, out Icon smallIcon, out Icon largeIcon)
{
if (fileName == null)
{
throw new ArgumentNullException("fileName");
}
smallIcon = null;
largeIcon = null;
RegistryKey registryKey1 = null;
RegistryKey registryKey2 = null;
try
{
FileInfo fileInfo = new FileInfo(fileName);
if (string.IsNullOrEmpty(fileInfo.Extension))
{
return;
}
string extension = fileInfo.Extension.ToLowerInvariant();
registryKey1 = Registry.ClassesRoot.OpenSubKey(extension);
if (registryKey1 == null)
{
return;
}
object extensionDefaultObject = registryKey1.GetValue(null);
if (!(extensionDefaultObject is string))
{
return;
}
string defaultIconKeyName = string.Format("{0}\\DefaultIcon", extensionDefaultObject);
registryKey2 = Registry.ClassesRoot.OpenSubKey(defaultIconKeyName);
if (registryKey2 == null)
{
return;
}
object defaultIconPathObject = registryKey2.GetValue(null);
if (!(defaultIconPathObject is string))
{
return;
}
string defaultIconPath = (string)defaultIconPathObject;
if (string.IsNullOrWhiteSpace(defaultIconPath))
{
return;
}
string iconfileName = null;
int iconIndex = 0;
int commaIndex = defaultIconPath.IndexOf(",");
if (commaIndex > 0)
{
iconfileName = defaultIconPath.Substring(0, commaIndex);
string iconIndexString = defaultIconPath.Substring(commaIndex + 1);
if (!int.TryParse(iconIndexString, out iconIndex))
{
iconIndex = 0;
}
}
else
{
iconfileName = defaultIconPath;
iconIndex = 0;
}
IntPtr[] phiconSmall = new IntPtr[1] { IntPtr.Zero };
IntPtr[] phiconLarge = new IntPtr[1] { IntPtr.Zero };
int readIconCount = ExtractIconEx(iconfileName, iconIndex, phiconLarge, phiconSmall, 1);
if (readIconCount < 0)
{
return;
}
if (phiconSmall[0] != IntPtr.Zero)
{
smallIcon = (Icon)Icon.FromHandle(phiconSmall[0]).Clone();
DestroyIcon(phiconSmall[0]);
}
if (phiconLarge[0] != IntPtr.Zero)
{
largeIcon = (Icon)Icon.FromHandle(phiconLarge[0]).Clone();
DestroyIcon(phiconLarge[0]);
}
return;
}
finally
{
if (registryKey2 != null)
{
registryKey2.Close();
}
if (registryKey1 != null)
{
registryKey1.Close();
}
}
}
}
用法:
string fileName = "NotExists.txt";
string contentType = Helper.GetFileContentType(fileName); // "text/plain"
string description = Helper.GetFileDescription(fileName); // "Text Document"
Icon smallIcon, largeIcon;
Helper.GetFileIcons(fileName, out smallIcon, out largeIcon); // 16x16, 32x32 icons
