MIME：全稱Multipurpose Internet Mail Extensions，多功能Internet 郵件擴充服務。它是一種多用途網際郵件擴充協議，在1992年最早應用於電子郵件系統，但後來也應用到瀏覽器。MIME型別就是設定某種副檔名的檔案用一種應用程式來開啟的方式型別，當該副檔名檔案被訪問的時候，瀏覽器會自動使用指定應用程式來開啟。多用於指定一些客戶端自定義的檔名，以及一些媒體檔案開啟方式。

在Android中通過檔案的MIME型別來判斷有哪些應用程式可以處理這些檔案，並使用其中的某一個應用程式（如果有多個可選的應用程式，則使用者必須指定一個）處理之。

我在寫android資源管理器（檔案瀏覽器）的時候，希望能在資源管理器的中實現開啟檔案的操作，此時就需要用到檔案的MIME型別。

實現方法：

private void openFile(File file){
 //Uri uri = Uri.parse("file://" + file.getAbsolutePath()); 
 Intent intent = new Intent();
 intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
 //設定intent的Action屬性 
 intent.setAction(Intent.ACTION_VIEW);
 //獲取檔案file的MIME型別 
 String type = getMIMEType(file);
 //設定intent的data和Type屬性。 
 intent.setDataAndType(Uri.fromFile(file), type);
 //跳轉 
 startActivity(intent);
 }
 

private String getMIMEType(File file){
 String type="* 
 String end=fName.substring(dotIndex + 1,fName.length()).toLowerCase();
 if(end=="")return type;
 //在MIME和檔案型別的匹配表中找到對應的MIME型別。 
 for(int i=0;i<MIME_MapTable.length;i++){
 if(end.equals(MIME_MapTable[i][0]))
 type = MIME_MapTable[i][1];
 }
 return type;
 }
 

現在就差一個MIME型別和檔案型別的匹配表了。
"檔案型別——MIME型別"的匹配表:

     private static final String[][] MIME_MapTable = {
        //{字尾名，MIME型別}
        {"3gp", "video/3gpp"},
        {"aab", "application/x-authoware-bin"},
        {"aam", "application/x-authoware-map"},
        {"aas", "application/x-authoware-seg"},
        {"ai", "application/postscript"},
        {"aif", "audio/x-aiff"},
        {"aifc", "audio/x-aiff"},
        {"aiff", "audio/x-aiff"},
        {"als", "audio/X-Alpha5"},
        {"amc", "application/x-mpeg"},
        {"ani", "application/octet-stream"},
        {"apk", "application/vnd.android.package-archive"},
        {"asc", "text/plain"},
        {"asd", "application/astound"},
        {"asf", "video/x-ms-asf"},
        {"asn", "application/astound"},
        {"asp", "application/x-asap"},
        {"asx", "video/x-ms-asf"},
        {"au", "audio/basic"},
        {"avb", "application/octet-stream"},
        {"avi", "video/x-msvideo"},
        {"awb", "audio/amr-wb"},
        {"bcpio", "application/x-bcpio"},
        {"bin", "application/octet-stream"},
        {"bld", "application/bld"},
        {"bld2", "application/bld2"},
        {"bmp", "image/bmp"},
        {"bpk", "application/octet-stream"},
        {"bz2", "application/x-bzip2"},
        {"c", "text/plain"},
        {"cal", "image/x-cals"},
        {"ccn", "application/x-cnc"},
        {"cco", "application/x-cocoa"},
        {"cdf", "application/x-netcdf"},
        {"cgi", "magnus-internal/cgi"},
        {"chat", "application/x-chat"},
        {"class", "application/octet-stream"},
        {"clp", "application/x-msclip"},
        {"cmx", "application/x-cmx"},
        {"co", "application/x-cult3d-object"},
        {"cod", "image/cis-cod"},
        {"conf", "text/plain"},
        {"cpio", "application/x-cpio"},
        {"cpp", "text/plain"},
        {"cpt", "application/mac-compactpro"},
        {"crd", "application/x-mscardfile"},
        {"csh", "application/x-csh"},
        {"csm", "chemical/x-csml"},
        {"csml", "chemical/x-csml"},
        {"css", "text/css"},
        {"cur", "application/octet-stream"},
        {"dcm", "x-lml/x-evm"},
        {"dcr", "application/x-director"},
        {"dcx", "image/x-dcx"},
        {"dhtml", "text/html"},
        {"dir", "application/x-director"},
        {"dll", "application/octet-stream"},
        {"dmg", "application/octet-stream"},
        {"dms", "application/octet-stream"},
        {"doc", "application/msword"},
        {"docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document"},
        {"dot", "application/x-dot"},
        {"dvi", "application/x-dvi"},
        {"dwf", "drawing/x-dwf"},
        {"dwg", "application/x-autocad"},
        {"dxf", "application/x-autocad"},
        {"dxr", "application/x-director"},
        {"ebk", "application/x-expandedbook"},
        {"emb", "chemical/x-embl-dl-nucleotide"},
        {"embl", "chemical/x-embl-dl-nucleotide"},
        {"eps", "application/postscript"},
        {"eri", "image/x-eri"},
        {"es", "audio/echospeech"},
        {"esl", "audio/echospeech"},
        {"etc", "application/x-earthtime"},
        {"etx", "text/x-setext"},
        {"evm", "x-lml/x-evm"},
        {"evy", "application/x-envoy"},
        {"exe", "application/octet-stream"},
        {"fh4", "image/x-freehand"},
        {"fh5", "image/x-freehand"},
        {"fhc", "image/x-freehand"},
        {"fif", "image/fif"},
        {"fm", "application/x-maker"},
        {"fpx", "image/x-fpx"},
        {"fvi", "video/isivideo"},
        {"gau", "chemical/x-gaussian-input"},
        {"gca", "application/x-gca-compressed"},
        {"gdb", "x-lml/x-gdb"},
        {"gif", "image/gif"},
        {"gps", "application/x-gps"},
        {"gtar", "application/x-gtar"},
        {"gz", "application/x-gzip"},
        {"h", "text/plain"},
        {"hdf", "application/x-hdf"},
        {"hdm", "text/x-hdml"},
        {"hdml", "text/x-hdml"},
        {"hlp", "application/winhlp"},
        {"hqx", "application/mac-binhex40"},
        {"htm", "text/html"},
        {"html", "text/html"},
        {"hts", "text/html"},
        {"ice", "x-conference/x-cooltalk"},
        {"ico", "application/octet-stream"},
        {"ief", "image/ief"},
        {"ifm", "image/gif"},
        {"ifs", "image/ifs"},
        {"imy", "audio/melody"},
        {"ins", "application/x-NET-Install"},
        {"ips", "application/x-ipscript"},
        {"ipx", "application/x-ipix"},
        {"it", "audio/x-mod"},
        {"itz", "audio/x-mod"},
        {"ivr", "i-world/i-vrml"},
        {"j2k", "image/j2k"},
        {"jad", "text/vnd.sun.j2me.app-descriptor"},
        {"jam", "application/x-jam"},
        {"jar", "application/java-archive"},
        {"java", "text/plain"},
        {"jnlp", "application/x-java-jnlp-file"},
        {"jpe", "image/jpeg"},
        {"jpeg", "image/jpeg"},
        {"jpg", "image/jpeg"},
        {"jpz", "image/jpeg"},
        {"js", "application/x-javascript"},
        {"jwc", "application/jwc"},
        {"kjx", "application/x-kjx"},
        {"lak", "x-lml/x-lak"},
        {"latex", "application/x-latex"},
        {"lcc", "application/fastman"},
        {"lcl", "application/x-digitalloca"},
        {"lcr", "application/x-digitalloca"},
        {"lgh", "application/lgh"},
        {"lha", "application/octet-stream"},
        {"lml", "x-lml/x-lml"},
        {"lmlpack", "x-lml/x-lmlpack"},
        {"log", "text/plain"},
        {"lsf", "video/x-ms-asf"},
        {"lsx", "video/x-ms-asf"},
        {"lzh", "application/x-lzh"},
        {"m13", "application/x-msmediaview"},
        {"m14", "application/x-msmediaview"},
        {"m15", "audio/x-mod"},
        {"m3u", "audio/x-mpegurl"},
        {"m3url", "audio/x-mpegurl"},
        {"m4a",    "audio/mp4a-latm"},
        {"m4b",    "audio/mp4a-latm"},
        {"m4p",    "audio/mp4a-latm"},
        {"m4u",    "video/vnd.mpegurl"},
        {"m4v",    "video/x-m4v"},
        {"ma1", "audio/ma1"},
        {"ma2", "audio/ma2"},
        {"ma3", "audio/ma3"},
        {"ma5", "audio/ma5"},
        {"man", "application/x-troff-man"},
        {"map", "magnus-internal/imagemap"},
        {"mbd", "application/mbedlet"},
        {"mct", "application/x-mascot"},
        {"mdb", "application/x-msaccess"},
        {"mdz", "audio/x-mod"},
        {"me", "application/x-troff-me"},
        {"mel", "text/x-vmel"},
        {"mi", "application/x-mif"},
        {"mid", "audio/midi"},
        {"midi", "audio/midi"},
        {"mif", "application/x-mif"},
        {"mil", "image/x-cals"},
        {"mio", "audio/x-mio"},
        {"mmf", "application/x-skt-lbs"},
        {"mng", "video/x-mng"},
        {"mny", "application/x-msmoney"},
        {"moc", "application/x-mocha"},
        {"mocha", "application/x-mocha"},
        {"mod", "audio/x-mod"},
        {"mof", "application/x-yumekara"},
        {"mol", "chemical/x-mdl-molfile"},
        {"mop", "chemical/x-mopac-input"},
        {"mov", "video/quicktime"},
        {"movie", "video/x-sgi-movie"},
        {"mp2", "audio/x-mpeg"},
        {"mp3", "audio/x-mpeg"},
        {"mp4", "video/mp4"},
        {"mpc", "application/vnd.mpohun.certificate"},
        {"mpe", "video/mpeg"},
        {"mpeg", "video/mpeg"},
        {"mpg video/mpeg"},
        {"mpg4", "video/mp4"},
        {"mpga", "audio/mpeg"},
        {"mpn", "application/vnd.mophun.application"},
        {"mpp", "application/vnd.ms-project"},
        {"mps", "application/x-mapserver"},
        {"mrl", "text/x-mrml"},
        {"mrm", "application/x-mrm"},
        {"ms", "application/x-troff-ms"},
        {"msg",     "application/vnd.ms-outlook"},
        {"mts", "application/metastream"},
        {"mtx", "application/metastream"},
        {"mtz", "application/metastream"},
        {"mzv", "application/metastream"},
        {"nar", "application/zip"},
        {"nbmp", "image/nbmp"},
        {"nc", "application/x-netcdf"},
        {"ndb", "x-lml/x-ndb"},
        {"ndwn", "application/ndwn"},
        {"nif", "application/x-nif"},
        {"nmz", "application/x-scream"},
        {"nokia-op-logo", "image/vnd.nok-oplogo-color"},
        {"npx", "application/x-netfpx"},
        {"nsnd", "audio/nsnd"},
        {"nva", "application/x-neva1"},
        {"oda", "application/oda"},
        {"ogg", "audio/ogg"},
        {"oom", "application/x-AtlasMate-Plugin"},
        {"pac", "audio/x-pac"},
        {"pae", "audio/x-epac"},
        {"pan", "application/x-pan"},
        {"pbm", "image/x-portable-bitmap"},
        {"pcx", "image/x-pcx"},
        {"pda", "image/x-pda"},
        {"pdb", "chemical/x-pdb"},
        {"pdf", "application/pdf"},
        {"pfr", "application/font-tdpfr"},
        {"pgm", "image/x-portable-graymap"},
        {"pict", "image/x-pict"},
        {"pm", "application/x-perl"},
        {"pmd", "application/x-pmd"},
        {"png", "image/png"},
        {"pnm", "image/x-portable-anymap"},
        {"pnz", "image/png"},
        {"pot", "application/vnd.ms-powerpoint"},
        {"ppm", "image/x-portable-pixmap"},
        {"pps", "application/vnd.ms-powerpoint"},
        {"ppt", "application/vnd.ms-powerpoint"},
        {"pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation"},
        {"pqf", "application/x-cprplayer"},
        {"pqi", "application/cprplayer"},
        {"prc", "application/x-prc"},
        {"prop", "text/plain"},
        {"proxy", "application/x-ns-proxy-autoconfig"},
        {"ps", "application/postscript"},
        {"ptlk", "application/listenup"},
        {"pub", "application/x-mspublisher"},
        {"pvx", "video/x-pv-pvx"},
        {"qcp", "audio/vnd.qcelp"},
        {"qt", "video/quicktime"},
        {"qti", "image/x-quicktime"},
        {"qtif", "image/x-quicktime"},
        {"r3t", "text/vnd.rn-realtext3d"},
        {"ra", "audio/x-pn-realaudio"},
        {"ram", "audio/x-pn-realaudio"},
        {"rar", "application/x-rar-compressed"},
        {"ras", "image/x-cmu-raster"},
        {"rc", "text/plain"},
        {"rdf", "application/rdf+xml"},
        {"rf", "image/vnd.rn-realflash"},
        {"rgb", "image/x-rgb"},
        {"rlf", "application/x-richlink"},
        {"rm", "audio/x-pn-realaudio"},
        {"rmf", "audio/x-rmf"},
        {"rmm", "audio/x-pn-realaudio"},
        {"rmvb", "audio/x-pn-realaudio"},
        {"rnx", "application/vnd.rn-realplayer"},
        {"roff", "application/x-troff"},
        {"rp", "image/vnd.rn-realpix"},
        {"rpm", "audio/x-pn-realaudio-plugin"},
        {"rt", "text/vnd.rn-realtext"},
        {"rte", "x-lml/x-gps"},
        {"rtf", "application/rtf"},
        {"rtg", "application/metastream"},
        {"rtx", "text/richtext"},
        {"rv", "video/vnd.rn-realvideo"},
        {"rwc", "application/x-rogerwilco"},
        {"s3m", "audio/x-mod"},
        {"s3z", "audio/x-mod"},
        {"sca", "application/x-supercard"},
        {"scd", "application/x-msschedule"},
        {"sdf", "application/e-score"},
        {"sea", "application/x-stuffit"},
        {"sgm", "text/x-sgml"},
        {"sgml", "text/x-sgml"},
        {"sh", "application/x-sh"},
        {"shar", "application/x-shar"},
        {"shtml", "magnus-internal/parsed-html"},
        {"shw", "application/presentations"},
        {"si6", "image/si6"},
        {"si7", "image/vnd.stiwap.sis"},
        {"si9", "image/vnd.lgtwap.sis"},
        {"sis", "application/vnd.symbian.install"},
        {"sit", "application/x-stuffit"},
        {"skd", "application/x-Koan"},
        {"skm", "application/x-Koan"},
        {"skp", "application/x-Koan"},
        {"skt", "application/x-Koan"},
        {"slc", "application/x-salsa"},
        {"smd", "audio/x-smd"},
        {"smi", "application/smil"},
        {"smil", "application/smil"},
        {"smp", "application/studiom"},
        {"smz", "audio/x-smd"},
        {"snd", "audio/basic"},
        {"spc", "text/x-speech"},
        {"spl", "application/futuresplash"},
        {"spr", "application/x-sprite"},
        {"sprite", "application/x-sprite"},
        {"spt", "application/x-spt"},
        {"src", "application/x-wais-source"},
        {"stk", "application/hyperstudio"},
        {"stm", "audio/x-mod"},
        {"sv4cpio", "application/x-sv4cpio"},
        {"sv4crc", "application/x-sv4crc"},
        {"svf", "image/vnd"},
        {"svg", "image/svg-xml"},
        {"svh", "image/svh"},
        {"svr", "x-world/x-svr"},
        {"swf", "application/x-shockwave-flash"},
        {"swfl", "application/x-shockwave-flash"},
        {"t", "application/x-troff"},
        {"tad", "application/octet-stream"},
        {"talk", "text/x-speech"},
        {"tar", "application/x-tar"},
        {"taz", "application/x-tar"},
        {"tbp", "application/x-timbuktu"},
        {"tbt", "application/x-timbuktu"},
        {"tcl", "application/x-tcl"},
        {"tex", "application/x-tex"},
        {"texi", "application/x-texinfo"},
        {"texinfo", "application/x-texinfo"},
        {"tgz", "application/x-tar"},
        {"thm", "application/vnd.eri.thm"},
        {"tif", "image/tiff"},
        {"tiff", "image/tiff"},
        {"tki", "application/x-tkined"},
        {"tkined", "application/x-tkined"},
        {"toc", "application/toc"},
        {"toy", "image/toy"},
        {"tr", "application/x-troff"},
        {"trk", "x-lml/x-gps"},
        {"trm", "application/x-msterminal"},
        {"tsi", "audio/tsplayer"},
        {"tsp", "application/dsptype"},
        {"tsv", "text/tab-separated-values"},
        {"tsv", "text/tab-separated-values"},
        {"ttf", "application/octet-stream"},
        {"ttz", "application/t-time"},
        {"txt", "text/plain"},
        {"ult", "audio/x-mod"},
        {"ustar", "application/x-ustar"},
        {"uu", "application/x-uuencode"},
        {"uue", "application/x-uuencode"},
        {"vcd", "application/x-cdlink"},
        {"vcf", "text/x-vcard"},
        {"vdo", "video/vdo"},
        {"vib", "audio/vib"},
        {"viv", "video/vivo"},
        {"vivo", "video/vivo"},
        {"vmd", "application/vocaltec-media-desc"},
        {"vmf", "application/vocaltec-media-file"},
        {"vmi", "application/x-dreamcast-vms-info"},
        {"vms", "application/x-dreamcast-vms"},
        {"vox", "audio/voxware"},
        {"vqe", "audio/x-twinvq-plugin"},
        {"vqf", "audio/x-twinvq"},
        {"vql", "audio/x-twinvq"},
        {"vre", "x-world/x-vream"},
        {"vrml", "x-world/x-vrml"},
        {"vrt", "x-world/x-vrt"},
        {"vrw", "x-world/x-vream"},
        {"vts", "workbook/formulaone"},
        {"wav", "audio/x-wav"},
        {"wax", "audio/x-ms-wax"},
        {"wbmp", "image/vnd.wap.wbmp"},
        {"web", "application/vnd.xara"},
        {"wi", "image/wavelet"},
        {"wis", "application/x-InstallShield"},
        {"wm", "video/x-ms-wm"},
        {"wma", "audio/x-ms-wma"},
        {"wmd", "application/x-ms-wmd"},
        {"wmf", "application/x-msmetafile"},
        {"wml", "text/vnd.wap.wml"},
        {"wmlc", "application/vnd.wap.wmlc"},
        {"wmls", "text/vnd.wap.wmlscript"},
        {"wmlsc", "application/vnd.wap.wmlscriptc"},
        {"wmlscript", "text/vnd.wap.wmlscript"},
        {"wmv", "audio/x-ms-wmv"},
        {"wmx", "video/x-ms-wmx"},
        {"wmz", "application/x-ms-wmz"},
        {"wpng", "image/x-up-wpng"},
        {"wps", "application/vnd.ms-works"},
        {"wpt", "x-lml/x-gps"},
        {"wri", "application/x-mswrite"},
        {"wrl", "x-world/x-vrml"},
        {"wrz", "x-world/x-vrml"},
        {"ws", "text/vnd.wap.wmlscript"},
        {"wsc", "application/vnd.wap.wmlscriptc"},
        {"wv", "video/wavelet"},
        {"wvx", "video/x-ms-wvx"},
        {"wxl", "application/x-wxl"},
        {"x-gzip", "application/x-gzip"},
        {"xar", "application/vnd.xara"},
        {"xbm", "image/x-xbitmap"},
        {"xdm", "application/x-xdma"},
        {"xdma", "application/x-xdma"},
        {"xdw", "application/vnd.fujixerox.docuworks"},
        {"xht", "application/xhtml+xml"},
        {"xhtm", "application/xhtml+xml"},
        {"xhtml", "application/xhtml+xml"},
        {"xla", "application/vnd.ms-excel"},
        {"xlc", "application/vnd.ms-excel"},
        {"xll", "application/x-excel"},
        {"xlm", "application/vnd.ms-excel"},
        {"xls", "application/vnd.ms-excel"},
        {"xlt", "application/vnd.ms-excel"},
        {"xlw", "application/vnd.ms-excel"},
        {"xlsx",      "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"},
        {"xm", "audio/x-mod"},
        {"xml", "text/xml"},
        {"xmz", "audio/x-mod"},
        {"xpi", "application/x-xpinstall"},
        {"xpm", "image/x-xpixmap"},
        {"xsit", "text/xml"},
        {"xsl", "text/xml"},
        {"xul", "text/xul"},
        {"xwd", "image/x-xwindowdump"},
        {"xyz", "chemical/x-pdb"},
        {"yz1", "application/x-yz1"},
        {"z", "application/x-compress"},
        {"zac", "application/x-zaurus-zac"},
        {"zip", "application/zip"},
        {"", "*/*"}
    };

 如果有新的檔案字尾，以及相應的MIME型別，只需要往表MIME_MapTable新增對應的條目即可。