how to detect iMessage and Text Message

[ninjacoderz]

when I send for new number at the first time, if that number is not registered as iMessage, it always failed and I need resend it another time. and this time, it send as textmessage
Question: How can I detect and do something for sending message.

[ayueyue321]

You need to set up your phone to use SMS to send when Imessage fails to send