How do I submit a “file” input without submit butt

问题:

There is a way to automatically submit a form without clicking to a "submit" button?

I have a form with one "file" input. I would submit the form after the user have selected one file.

回答1:

yes, you can use the form.submit() function. Add an onchange listener on the file input and link it to the form.submit function, like so:

<form action="upload.php" method="post">
<input type="file" onchange="this.form.submit()" name="myFile"/>
</form>

回答2:

Yes, you can add the following to the onchange event of the file input:

<input type='file' .... onchange='this.form.submit();'>

this submits the form right after the user has picked a file. However, the user can't correct a mistaken selection before submitting - be sure to check whether this is really wise.

回答3:

This solution works for me.

<form enctype="multipart/form-data" method="POST" action="/upload">
  <input id="myfilefield" type="file" name="file">
  <input type="submit">
</form>

 

document.getElementById('myfilefield').onchange = function() {
  this.form.submit();
};

By the way, you don't need to use flash. Gmail do it by XHR Level 2.

回答4:

I don't believe you can do this. Browsers are very, very strict about what you can do to file upload fields, because of the potential for abuse. If the user accidentally selects a private file, they wouldn't want it to immediately start uploading that file to a random server.

回答5:

I'm not sure what the restrictions are with doing this in an HTML form.

You can, however, do it with Flash. Gmail does it - when I click "Attach a file", I get prompted with a file browse dialog, and when I OK that dialog the upload begins immediately, and also gives me a progress bar.

Googling for "Flash uploader" will give you many options, but I don't have experience with any of them.