<转载> http中content-type头的值(MIME类型)
An official listing of defined MIME types:
.ai - application/postscript
.aif - audio/x-aiff
.aifc - audio/x-aiff
.aiff - audio/x-aiff
.asc - text/plain
.au - audio/basic
.avi - video/x-msvideo
.bcpio - application/x-bcpio
.bin - application/octet-stream
.c - text/plain
.cc - text/plain
.ccad - application/clariscad
.cdf - application/x-netcdf
.class - application/octet-stream
.cpio - application/x-cpio
.cpt - application/mac-compactpro
.csh - application/x-csh
.css - text/css
.dcr - application/x-director
.dir - application/x-director
.dms - application/octet-stream
.doc - application/msword
.drw - application/drafting
.dvi - application/x-dvi
.dwg - application/acad
.dxf - application/dxf
.dxr - application/x-director
.eps - application/postscript
.etx - text/x-setext
.exe - application/octet-stream
.ez - application/andrew-inset
.f - text/plain
.f90 - text/plain
.fli - video/x-fli
.gif - image/gif
.gtar - application/x-gtar
.gz - application/x-gzip
.h - text/plain
.hdf - application/x-hdf
.hh - text/plain
.hqx - application/mac-binhex40
.htm - text/html
.html - text/html
.ice - x-conference/x-cooltalk
.ief - image/ief
.iges - model/iges
.igs - model/iges
.ips - application/x-ipscript
.ipx - application/x-ipix
.jpe - image/jpeg
.jpeg - image/jpeg
.jpg - image/jpeg
.js - application/x-javascript
.kar - audio/midi
.latex - application/x-latex
.lha - application/octet-stream
.lsp - application/x-lisp
.lzh - application/octet-stream
.m - text/plain
.man - application/x-troff-man
.me - application/x-troff-me
.mesh - model/mesh
.mid - audio/midi
.midi - audio/midi
.mif - application/vnd.mif
.mime - www/mime
.mov - video/quicktime
.movie - video/x-sgi-movie
.mp2 - audio/mpeg
.mp3 - audio/mpeg
.mpe - video/mpeg
.mpeg - video/mpeg
.mpg - video/mpeg
.mpga - audio/mpeg
.ms - application/x-troff-ms
.msh - model/mesh
.nc - application/x-netcdf
.oda - application/oda
.pbm - image/x-portable-bitmap
.pdb - chemical/x-pdb
.pdf - application/pdf
.pgm - image/x-portable-graymap
.pgn - application/x-chess-pgn
.png - image/png
.pnm - image/x-portable-anymap
.pot - application/mspowerpoint
.ppm - image/x-portable-pixmap
.pps - application/mspowerpoint
.ppt - application/mspowerpoint
.ppz - application/mspowerpoint
.pre - application/x-freelance
.prt - application/pro_eng
.ps - application/postscript
.qt - video/quicktime
.ra - audio/x-realaudio
.ram - audio/x-pn-realaudio
.ras - image/cmu-raster
.rgb - image/x-rgb
.rm - audio/x-pn-realaudio
.roff - application/x-troff
.rpm - audio/x-pn-realaudio-plugin
.rtf - text/rtf
.rtx - text/richtext
.scm - application/x-lotusscreencam
.set - application/set
.sgm - text/sgml
.sgml - text/sgml
.sh - application/x-sh
.shar - application/x-shar
.silo - model/mesh
.sit - application/x-stuffit
.skd - application/x-koan
.skm - application/x-koan
.skp - application/x-koan
.skt - application/x-koan
.smi - application/smil
.smil - application/smil
.snd - audio/basic
.sol - application/solids
.spl - application/x-futuresplash
.src - application/x-wais-source
.step - application/STEP
.stl - application/SLA
.stp - application/STEP
.sv4cpio - application/x-sv4cpio
.sv4crc - application/x-sv4crc
.swf - application/x-shockwave-flash
.t - application/x-troff
.tar - application/x-tar
.tcl - application/x-tcl
.tex - application/x-tex
.texi - application/x-texinfo
.texinfo - application/x-texinfo
.tif - image/tiff
.tiff - image/tiff
.tr - application/x-troff
.tsi - audio/TSP-audio
.tsp - application/dsptype
.tsv - text/tab-separated-values
.txt - text/plain
.unv - application/i-deas
.ustar - application/x-ustar
.vcd - application/x-cdlink
.vda - application/vda
.viv - video/vnd.vivo
.vivo - video/vnd.vivo
.vrml - model/vrml
.wav - audio/x-wav
.wrl - model/vrml
.xbm - image/x-xbitmap
.xlc - application/vnd.ms-excel
.xll - application/vnd.ms-excel
.xlm - application/vnd.ms-excel
.xls - application/vnd.ms-excel
.xlw - application/vnd.ms-excel
.xml - text/xml
.xpm - image/x-xpixmap
.xwd - image/x-xwindowdump
.xyz - chemical/x-pdb
.zip - application/zip