Implementing a file upload under html is fairly simple, but I just noticed that there is an \'accept\' attribute that can be added to the
Yes, it is extremely useful in browsers that support it, but the "limiting" is as a convenience to users (so they are not overwhelmed with irrelevant files) rather than as a way to prevent them from uploading things you don't want them uploading.
It is supported in
Here is a list of content types you can use with it, followed by the corresponding file extensions (though of course you can use any file extension):
application/envoy evy
application/fractals fif
application/futuresplash spl
application/hta hta
application/internet-property-stream acx
application/mac-binhex40 hqx
application/msword doc
application/msword dot
application/octet-stream *
application/octet-stream bin
application/octet-stream class
application/octet-stream dms
application/octet-stream exe
application/octet-stream lha
application/octet-stream lzh
application/oda oda
application/olescript axs
application/pdf pdf
application/pics-rules prf
application/pkcs10 p10
application/pkix-crl crl
application/postscript ai
application/postscript eps
application/postscript ps
application/rtf rtf
application/set-payment-initiation setpay
application/set-registration-initiation setreg
application/vnd.ms-excel xla
application/vnd.ms-excel xlc
application/vnd.ms-excel xlm
application/vnd.ms-excel xls
application/vnd.ms-excel xlt
application/vnd.ms-excel xlw
application/vnd.ms-outlook msg
application/vnd.ms-pkicertstore sst
application/vnd.ms-pkiseccat cat
application/vnd.ms-pkistl stl
application/vnd.ms-powerpoint pot
application/vnd.ms-powerpoint pps
application/vnd.ms-powerpoint ppt
application/vnd.ms-project mpp
application/vnd.ms-works wcm
application/vnd.ms-works wdb
application/vnd.ms-works wks
application/vnd.ms-works wps
application/winhlp hlp
application/x-bcpio bcpio
application/x-cdf cdf
application/x-compress z
application/x-compressed tgz
application/x-cpio cpio
application/x-csh csh
application/x-director dcr
application/x-director dir
application/x-director dxr
application/x-dvi dvi
application/x-gtar gtar
application/x-gzip gz
application/x-hdf hdf
application/x-internet-signup ins
application/x-internet-signup isp
application/x-iphone iii
application/x-javascript js
application/x-latex latex
application/x-msaccess mdb
application/x-mscardfile crd
application/x-msclip clp
application/x-msdownload dll
application/x-msmediaview m13
application/x-msmediaview m14
application/x-msmediaview mvb
application/x-msmetafile wmf
application/x-msmoney mny
application/x-mspublisher pub
application/x-msschedule scd
application/x-msterminal trm
application/x-mswrite wri
application/x-netcdf cdf
application/x-netcdf nc
application/x-perfmon pma
application/x-perfmon pmc
application/x-perfmon pml
application/x-perfmon pmr
application/x-perfmon pmw
application/x-pkcs12 p12
application/x-pkcs12 pfx
application/x-pkcs7-certificates p7b
application/x-pkcs7-certificates spc
application/x-pkcs7-certreqresp p7r
application/x-pkcs7-mime p7c
application/x-pkcs7-mime p7m
application/x-pkcs7-signature p7s
application/x-sh sh
application/x-shar shar
application/x-shockwave-flash swf
application/x-stuffit sit
application/x-sv4cpio sv4cpio
application/x-sv4crc sv4crc
application/x-tar tar
application/x-tcl tcl
application/x-tex tex
application/x-texinfo texi
application/x-texinfo texinfo
application/x-troff roff
application/x-troff t
application/x-troff tr
application/x-troff-man man
application/x-troff-me me
application/x-troff-ms ms
application/x-ustar ustar
application/x-wais-source src
application/x-x509-ca-cert cer
application/x-x509-ca-cert crt
application/x-x509-ca-cert der
application/ynd.ms-pkipko pko
application/zip zip
audio/basic au
audio/basic snd
audio/mid mid
audio/mid rmi
audio/mpeg mp3
audio/x-aiff aif
audio/x-aiff aifc
audio/x-aiff aiff
audio/x-mpegurl m3u
audio/x-pn-realaudio ra
audio/x-pn-realaudio ram
audio/x-wav wav
image/bmp bmp
image/cis-cod cod
image/gif gif
image/ief ief
image/jpeg jpe
image/jpeg jpeg
image/jpeg jpg
image/pipeg jfif
image/svg+xml svg
image/tiff tif
image/tiff tiff
image/x-cmu-raster ras
image/x-cmx cmx
image/x-icon ico
image/x-portable-anymap pnm
image/x-portable-bitmap pbm
image/x-portable-graymap pgm
image/x-portable-pixmap ppm
image/x-rgb rgb
image/x-xbitmap xbm
image/x-xpixmap xpm
image/x-xwindowdump xwd
message/rfc822 mht
message/rfc822 mhtml
message/rfc822 nws
text/css css
text/h323 323
text/html htm
text/html html
text/html stm
text/iuls uls
text/plain bas
text/plain c
text/plain h
text/plain txt
text/richtext rtx
text/scriptlet sct
text/tab-separated-values tsv
text/webviewhtml htt
text/x-component htc
text/x-setext etx
text/x-vcard vcf
video/mpeg mp2
video/mpeg mpa
video/mpeg mpe
video/mpeg mpeg
video/mpeg mpg
video/mpeg mpv2
video/quicktime mov
video/quicktime qt
video/x-la-asf lsf
video/x-la-asf lsx
video/x-ms-asf asf
video/x-ms-asf asr
video/x-ms-asf asx
video/x-msvideo avi
video/x-sgi-movie movie
x-world/x-vrml flr
x-world/x-vrml vrml
x-world/x-vrml wrl
x-world/x-vrml wrz
x-world/x-vrml xaf
x-world/x-vrml xof