Can you manually list an address in a Smart Contract

Question

Can you manually list a wallet address in a smart contract transaction? For example lets say I create a smart contract that allows any user to send Ada to a specific address by sending it to the scripts UTXO address is this possible?

Answer 1

You could hardcode public key hash of a receiver address and then validate if outgoing transaction is going towards address with same public key hash.

Here is an example how that would look like in plutus code:

...
data ContractInfo = ContractInfo
{ 
   recvPkh :: !PubKeyHash
} deriving Show

contractInfo = ContractInfo
{ 
   recvPkh = "3f7846896a48c59359746ff096d63606ceb82e65900d20a9fd2b8a93"
}

{-# INLINABLE mkValidator #-}
mkValidator :: ContractInfo -> () -> () -> ScriptContext -> Bool
mkValidator contractInfo@ContractInfo{..} _ _ ctx =
  any outputToCorrectAddr txOuts
 where
     info :: TxInfo
     info = scriptContextTxInfo ctx

     txOuts :: [TxOut]
     txOuts = txInfoOutputs info

     outputToCorrectAddr :: TxOut -> Bool
     outputToCorrectAddr txo = case toPubKeyHash $ txOutAddress txo of
       Just pkh -> recvPkh == pkh
       Nothing  -> False
...