Don't allow duplicates of a file

Feature Request

Describe the solution you’d like

There should be a way to make sure users can’t upload 2 of the same files.

Describe alternatives you’ve considered

I’ve tried to do this outside of the dropzone, but there doesn’t seem to a way.

Teachability, Documentation, Adoption, Migration Strategy

It could just be a prop passed in called noDuplicates

Additional context

See my stack overflow question here: https://stackoverflow.com/questions/63198613/how-do-i-make-a-material-ui-dropzone-area-not-allow-duplicates

[Sheshank-s]

Since this is something many people would need, don’t you think it would be best to implement it as a feature?

[jrhager84]

Here is the boilerplate for you to use to filter out duplicates. Use DropzoneAreaBase instead to add your own handler for the onAdd onDelete methods.

  function addSongs(newSongs) {
    newSongs = newSongs.filter(song => !songs.find(f => f.data === song.data));
    setSongs([...songs, ...newSongs]);
  }

  function removeSong(deleted) {
    setSongs(songs.filter(f => f !== deleted))
    console.log(songs)
  }

this is using state via [songs, setSongs] for the fileObjects prop