sugiura

You can modify wpcf7-dropbox-script.js, in js directory of this plugin, using forEacn like beneath.

jQuery(document).ready(function() {
    wpcf7_dropbox_mailsent_handler();
});

function wpcf7_dropbox_mailsent_handler() {
	document.addEventListener( 'wpcf7mailsent', function( event ) {
		form = wpcf7_dropbox_forms [ event.detail.contactFormId ];

		if ( form.access_token && form.file_input ) {
			var accessToken = form.access_token;
			var dbx = new Dropbox({ accessToken: accessToken });

      var inputs = form.file_input.split(' ');

      inputs.forEach(function(val,index){
        var fileInput = document.getElementById(inputs[index]);
  			var file = fileInput.files[0];
  			if(file) {
  				dbx.filesUpload({path: '/' + file.name, contents: file})
  				.then(function(response) {
  				  console.log(response);
  				  console.log('File uploaded!');
  				})
  				.catch(function(error) {
  				  console.error(error);
  				});
  			}
      })
		}
		return false;

	}, false );
}

In this case, I use space for delimiter, so you have to fill the “file input id” like “file1 file2”.