MVC文件上传文件限制

最近想实现MVC中文件上传限制，总觉得有便利的方法，找了半天就找到加属性accept

<input type="file" id="file" name="file" accept="image/*"/>

accept表示可以上传文件类型，image表示图片，*表示所有支持的格式。

accept可写的类型如下(两种以上的用逗号隔开)：

文件类型‍	accept内容	格式说明
*.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

非MVC不知道怎么样，在MVC中使用过程中，选择文件的时候是限制了，但是提交的时候，会提示文件有问题，无法提交，去掉accept就可以提交，所以最好的办法其实是在javascript或者Jquery中限制。

 $(function (){
     $("#file").change(function () {
         var f = $("#file").val();
         if (f == '') {
             alert("请选择图片上传");
             return false;
         }
         else if (f.indexOf('.png') > -1 || f.indexOf('.jpg') > -1) {
             return true;
         } else {
             alert("只允许png或jpg格式图片");
             $("#file").val('');
             return false;
         }
     });
 });

Jquery

这里只是在改变事件中限制了，其实表单提交前应该还要在判断文件是否为空。