Hi,
I have a form in which you can load attach multiple documents, it is handled through 2 buttons, one to delete and one to add, normal in this case. By default, when we add that the control appears to load the document, it is necessary to load it, otherwise, the request can not be sent or forwarded.
I would like to know how I can place a notice to the user so that when I click on the add button and the attachment control is displayed, I placed the document and do not leave it empty, causing the request not to be sent.