在 JavaScript 中获取内容类型的默认文件扩展名？

Question

If I have a content-type, how can I get its default file extension?

For example, given one of these content-types, I should get the following file extensions:

+------------------------+----------------+
|      Content-Type      | File Extension |
+------------------------+----------------+
| text/plain             | .txt           |
| application/javascript | .js            |
| application/gzip       | .gz            |
+------------------------+----------------+

If there is no way to get these extensions automatically in JavaScript, my next solution would be to create a simple relationship between content-type and file extension in a JavaScript array. Therefore, I would accept an answer which has a simple table/database of the most common content-type and file extensions.

Answer 1

For Node applications, there is a more up-to-date answer now, which is to use the mime-types NPM package , eg:

var mime = require('mime-types'),
    fileExtension = mime.extension('text/plain');

Answer 2

from nginx

types {
    text/html                             html htm shtml;
    text/css                              css;
    text/xml                              xml;
    image/gif                             gif;
    image/jpeg                            jpeg jpg;
    application/x-javascript              js;
    application/atom+xml                  atom;
    application/rss+xml                   rss;

    text/mathml                           mml;
    text/plain                            txt;
    text/vnd.sun.j2me.app-descriptor      jad;
    text/vnd.wap.wml                      wml;
    text/x-component                      htc;

    image/png                             png;
    image/tiff                            tif tiff;
    image/vnd.wap.wbmp                    wbmp;
    image/x-icon                          ico;
    image/x-jng                           jng;
    image/x-ms-bmp                        bmp;
    image/svg+xml                         svg;
    image/webp                            webp;

    application/java-archive              jar war ear;
    application/mac-binhex40              hqx;
    application/msword                    doc;
    application/pdf                       pdf;
    application/postscript                ps eps ai;
    application/rtf                       rtf;
    application/vnd.ms-excel              xls;
    application/vnd.ms-powerpoint         ppt;
    application/vnd.wap.wmlc              wmlc;
    application/vnd.google-earth.kml+xml  kml;
    application/vnd.google-earth.kmz      kmz;
    application/x-7z-compressed           7z;
    application/x-cocoa                   cco;
    application/x-java-archive-diff       jardiff;
    application/x-java-jnlp-file          jnlp;
    application/x-makeself                run;
    application/x-perl                    pl pm;
    application/x-pilot                   prc pdb;
    application/x-rar-compressed          rar;
    application/x-redhat-package-manager  rpm;
    application/x-sea                     sea;
    application/x-shockwave-flash         swf;
    application/x-stuffit                 sit;
    application/x-tcl                     tcl tk;
    application/x-x509-ca-cert            der pem crt;
    application/x-xpinstall               xpi;
    application/xhtml+xml                 xhtml;
    application/zip                       zip;

    application/octet-stream              bin exe dll;
    application/octet-stream              deb;
    application/octet-stream              dmg;
    application/octet-stream              eot;
    application/octet-stream              iso img;
    application/octet-stream              msi msp msm;

    audio/midi                            mid midi kar;
    audio/mpeg                            mp3;
    audio/ogg                             ogg;
    audio/x-realaudio                     ra;

    video/3gpp                            3gpp 3gp;
    video/mpeg                            mpeg mpg;
    video/quicktime                       mov;
    video/x-flv                           flv;
    video/x-mng                           mng;
    video/x-ms-asf                        asx asf;
    video/x-ms-wmv                        wmv;
    video/x-msvideo                       avi;
    video/mp4                             m4v mp4;
}

Answer 3

There is a best package is

mime-db lib npm

var mimeDb = require("mime-db")

usage(it return object)

var data = mimeDb['image/x-icon']
console.log(data)

To get extenstions

 console.log(data.extensions[0])

another one is mime-types derived from mime-db

mime types

but while i use mime types little bugy in getting extension image/x-icon