Image Preview

var uploader = new MultipleUpload(el, {
 uploadUrl: '/api/upload',
 accept: 'image/*',
 showThumbnails: true,
 thumbnailSize: 120        // longest edge in px; default 64
});

Seeing the file before it goes

showThumbnails defaults to true, and previews are generated in the browser — nothing is uploaded to produce them. thumbnailSize sets the longest edge in pixels and defaults to 64; the component renders at a higher internal resolution so the result stays sharp on a high-density display.

The check that costs nothing

A preview is how the user notices they picked the wrong screenshot before waiting for it to upload. That is worth most when several files are selected at once, which is exactly when a mistake is easiest to make and hardest to spot in a list of file names.