input文件选择，限定文件类型

当使用input提交文件时，用accept方法，可以限制上传文件的类型。

如：

&ltinput type="file" name="upload" multiple="multiple" accept=".zip">

accept可以指定的常见类型：

(使用时，用如上的.zip就可以了)

*.3gpp audio/3gpp, video/3gpp 3GPP Audio/Video

*.ac3 audio/ac3 AC3 Audio

*.asf allpication/vnd.ms-asf Advanced Streaming Format

*.au audio/basic AU Audio

*.css text/css Cascading Style Sheets

*.csv text/csv Comma Separated Values

*.doc application/msword MS Word Document

*.dot application/msword MS Word Template

*.dtd application/xml-dtd Document Type Definition

*.dwg image/vnd.dwg AutoCAD Drawing Database

*.dxf image/vnd.dxf AutoCAD Drawing Interchange Format

*.gif image/gif Graphic Interchange Format

*.htm text/html HyperText Markup Language

*.html text/html HyperText Markup Language

*.jp2 image/jp2 JPEG-2000

*.jpe image/jpeg JPEG

*.jpeg image/jpeg JPEG

*.jpg image/jpeg JPEG

*.js text/javascript, application/javascript JavaScript

*.json application/json JavaScript Object Notation

*.mp2 audio/mpeg, video/mpeg MPEG Audio/Video Stream, Layer II

*.mp3 audio/mpeg MPEG Audio Stream, Layer III

*.mp4 audio/mp4, video/mp4 MPEG-4 Audio/Video

*.mpeg video/mpeg MPEG Video Stream, Layer II

*.mpg video/mpeg MPEG Video Stream, Layer II

*.mpp application/vnd.ms-project MS Project Project

*.ogg application/ogg, audio/ogg Ogg Vorbis

*.pdf application/pdf Portable Document Format

*.png image/png Portable Network Graphics

*.pot application/vnd.ms-powerpoint MS PowerPoint Template

*.pps application/vnd.ms-powerpoint MS PowerPoint Slideshow

*.ppt application/vnd.ms-powerpoint MS PowerPoint Presentation

*.rtf application/rtf, text/rtf Rich Text Format

*.svf image/vnd.svf Simple Vector Format

*.tif image/tiff Tagged Image Format File

*.tiff image/tiff Tagged Image Format File

*.txt text/plain Plain Text

*.wdb application/vnd.ms-works MS Works Database

*.wps application/vnd.ms-works Works Text Document

*.xhtml application/xhtml+xml Extensible HyperText Markup Language

*.xlc application/vnd.ms-excel MS Excel Chart

*.xlm application/vnd.ms-excel MS Excel Macro

*.xls application/vnd.ms-excel MS Excel Spreadsheet

*.xlt application/vnd.ms-excel MS Excel Template

*.xlw application/vnd.ms-excel MS Excel Workspace

*.xml text/xml, application/xml Extensible Markup Language

*.zip aplication/zip Compressed Archive

input文件选择，限定文件类型。你学会了吗？:)