File Input accept Attribute
The HTML5 revolution provided us several simple but important attributes like download, autofocus, required, novalidate, and placeholder. There's another one you may want to know about: accept. The accept attribute is useful for input[type=file] elements. Let's have a look at it!
The HTML
I'll use Twitter's upload button to illustrate a good usage of the accept attribute:
<input type="file" name="media_empty" accept="image/gif,image/jpeg,image/jpg,image/png,">
The accept attribute gets a comma-separated list of mime types for files desired file types. In this case, Twitter is allowing the user to upload common image formats.
![From Webcam to Animated GIF: the Secret Behind chat.meatspac.es!]()
My team mate Edna Piranha is not only an awesome hacker; she's also a fantastic philosopher! Communication and online interactions is a subject that has kept her mind busy for a long time, and it has also resulted in a bunch of interesting experimental projects...
![CSS 3D Folding Animation]()
Google Plus provides loads of inspiration for front-end developers, especially when it comes to the CSS and JavaScript wonders they create. Last year I duplicated their incredible PhotoStack effect with both MooTools and pure CSS; this time I'm going to duplicate...
![Use Custom Missing Image Graphics Using jQuery]()
![Create a Twitter AJAX Button with MooTools, jQuery, or Dojo]()
There's nothing like a subtle, slick website widget that effectively uses CSS and JavaScript to enhance the user experience. Of course widgets like that take many hours to perfect, but it doesn't take long for that effort to be rewarded with above-average user retention and...
The biggest problem about using this code is that the user can change it easily with firebug or others debugs.
It’s not for validation, it’s for assisting the user to select the right file type (since the file selection will only show files of that type).
You should never use this for validation since some browsers do not support it.
Validation should be done on your backend. This kind of selection only helps users what we really need from them.
Be careful with this.
The main issue is that some mobile browsers started to prevent the user from selecting any (!) file at all if the accept property was declared (which is just plain terrible user agent behaviour).
Thus if you want to support these browsers, you have to detect them and remove the accept property.
For details see http://caniuse.com/#feat=input-file-accept