I want to enable an action (sendmail) only if the two conditions are true:

1) Text field "SenttoEncode" has no text entered
2) Radio button is set to "No"

How do I write the "if" statement to do something when the two conditions are met? I have tried:

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

Neither of these work as the next step is to send an email if the condition is true, and even though the text field "SenttoEncode" is empty the email still gets sent. Can someone guide me in the right direction on how to make this happen?

Thanks is advance