Using "if" statement if nothing is selected in multi select box

Using "if" statement if nothing is selected in multi select box

I would like to send an email only if at least one item is selected in a multi select box. However, I am not sure how to do this. I've tried (see highlighted text):

if ((((input.SenttoEncode  !=  "")  &&  (input.STPandDolby  ==  "No"))  &&  (input.Force_Eval_Email  ==  "No"))  &&  (input.Videographer  !=  null))

and

if ((((input.SenttoEncode  !=  "")  &&  (input.STPandDolby  ==  "No"))  &&  (input.Force_Eval_Email  ==  "No"))  &&  (input.Videographer  !=  ""))

but neither of these work. What is the proper way to write this so that the statement is only true if at least one item is selected in the multi select box? By default there is nothing selected in the box; the user must manually select the item(s).
Thanks