I'm working on a file uploader in js and want to check if a file is currently open in another process which will prevent upload to the site. The upload is a

<input type="file"

which supports both drag n drop as well as using the OS filechooser.

Currently the file, if open in e.g, Excel, will not be selected on drag and drop and I'd like to catch that to display appropriate error message. Thank you

CodePudding user response：

Browsers provide no APIs that would make this possible. You can't do it.