superfile

Intro

An ES6 class to improve uploaders. Works great with Bootstrap but works with any input.

• Resize image on client side to avoid large uploads
• Preview image
• Clear uploads
• Crop to ratio
• Drop support
• Multiple/directory upload support

How to use

import Superfile from "./superfile.js";
Superfile.init();

Create a file input. It needs to be wrapped by a div with the superfile class.

You can add a clear button and a preview image if you want.

<div class="mb-3 superfile">
    <label for="formFile" class="form-label">Default file input example</label>
    <div class="input-group">
    <input class="form-control" type="file" id="formFile" name="file" />
    <button class="btn btn-outline-secondary superfile-clear" type="button">Clear</button>
    </div>
    <img class="img-fluid superfile-preview" />
</div>

Available options

These are set through data attributes:

• disable-resize: don't try to resize the images and keep original files
• max-width: the maximum width of the image (keep ratio)
• max-height: the maximum height of the image (keep ratio)
• hide-clear: hide clear element (if any) until preview is showed
• ratio: set a ratio (eg: 1:1 for a square ratio) for the image. Image is cropped from the center. It can be used with max-width/max-height or independantly.

Limiting accepted file types

You can use the regular accept attribute.

<input type="file" accept=".gif,.jpg,.jpeg,.png,.doc,.docx">
<input type="file" accept="image/*">

Recommended css

• Hide preview element when no src is set
• Hide inputs until ready (avoids fouc)
• Change input background color when dropping files

img:not([src]) {
    display: none;
}
.superfile:not(.superfile-ready) {
    visibility: hidden;
}
.superfile-drag input {
    background: palegoldenrod;
}

When set, the preview will get a src attribute like blob:http://someaddress/30fde1c6-911e-4b50-a823-e778d100ffb3 and be displayed

Demo

https://codepen.io/lekoalabe/pen/wvdVoNa

I need more

This is a simple improvement over regular file input.

If you need more, look at :

• https://pqina.nl/filepond/
• https://www.dropzonejs.com/