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问题:

I want my uploader only allows these types:

doc, docx.
xls, xlsx.
ppt, pptx.
txt.
pdf.
Image types.

How can I achieve this? What should I put in the accept attribute? Thanks for your help.

EDIT!!!

I have one more thing to ask. When the popup appears for use to choose file, at the down right corner, there is a drop down list contains all allow files. In my case, the list would be long. I see in the list, there is an option called All Supported Types. How can I make it chosen by default and eliminate all other options?

Any help will be appreciated. Thank you.

回答1:

The value of the accept attribute is, as per HTML5 LC, a comma-separated list of items, each of which is a specific media type like image/gif, or a notation like image/* that refers to all image types, or a filename extension like .gif. IE 10+ and Chrome support all of these, whereas Firefox does not support the extensions. Thus, the safest way is to use media types and notations like image/*, in this case

<input type="file" name="foo" accept=
"application/msword, application/vnd.ms-excel, application/vnd.ms-powerpoint,
text/plain, application/pdf, image/*">

if I understand the intents correctly. Beware that browsers might not recognize the media type names exactly as specified in the authoritative registry, so some testing is needed.

回答2:

Use Like below

<input type="file" accept=".xlsx,.xls,image/*,.doc, .docx,.ppt, .pptx,.txt,.pdf" />

回答3:

Use accept attribute with the MIME_type as values

<input type="file" accept="image/gif, image/jpeg" />

回答4:

for powerpoint and pdf files:

<html>
<input type="file" placeholder="Do you have a .ppt?" name="pptfile" id="pptfile" accept="application/pdf,application/vnd.ms-powerpoint,application/vnd.openxmlformats-officedocument.presentationml.slideshow,application/vnd.openxmlformats-officedocument.presentationml.presentation"/>
</html>

回答5:

IMPORTANT UPDATE:

Due to use of only application/msword, application/vnd.ms-excel, application/vnd.ms-powerpoint... allows only till 2003 MS products, and not newest. I've found this:

application/msword, application/vnd.openxmlformats-officedocument.wordprocessingml.document, application/vnd.ms-powerpoint, application/vnd.openxmlformats-officedocument.presentationml.slideshow, application/vnd.openxmlformats-officedocument.presentationml.presentation

And that includes the new ones. For other files, you can retrieve the MIME TYPE in your file by this way (pardon the lang)(in MIME list types, there aren't this ones):

You can select & copy the type of content

回答6:

As stated on w3schools:

audio/* - All sound files are accepted

video/* - All video files are accepted

image/* - All image files are accepted

MIME_type - A valid MIME type, with no parameters. Look at IANA MIME types for a complete list of standard MIME types

回答7:

for image write this

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

For other, You can use the accept attribute on your form to suggest to the browser to restrict certain types. However, you'll want to re-validate in your server-side code to make sure. Never trust what the client sends you