Is there anyway to prevent a user from uploading a file based on filesize prior to the actual uploading of the files.

 I currently use:

        uploadSingleFileAttachments.ValidateOption.MaxSizeKB = maxUploadSizeBytes / 1024;

To handle it but if a user uploads a 8mb file and it takes then 2 minutes to do so they are only told they wasted their time uploading it after the fact.

 

is there a way to prevent them from uploading certain files at all??