Can't get transaction hash from signAndSend of Polkadot.js

Question

I'm new and I'm trying to get the transaction hash but I'm only getting undefined. I used this tutorial and this and below is my code.

const txHash = await polkadot.tx.balances
  .transfer('5F1pZe.....GmZRSZuK', 100000000000)
  .signAndSend(SENDER, { signer: injector.signer }, (status) => {

        if (status.isInBlock) {
            console.log(`Completed at block hash #${status.isInBlock}`);
        } else {
            console.log(`Current status: ${status.type}`);
        }


    }).catch((error) => {
        console.log(':( transaction failed', error);
    });

console.log("Submitted with hash", txHash.hash);

I'm getting undefined for txHash.hash, status.type. I have another code that works but I wonder what's wrong with the above.

Answer 1

The txhash is only returned when you use the non-subscribe form.

In code for the non-sub form -

// don't subscribe, txhash is returned
const txHash = await polkadot.tx.balances
  .transfer('5F1pZe.....GmZRSZuK', 100000000000)
  .signAndSend(SENDER, { signer: injector.signer });

console.log(txhash);

And for the subscription form -

// subscription, unsub is returned, txHash internal
const unsub = await polkadot.tx.balances
  .transfer('5F1pZe.....GmZRSZuK', 100000000000)
  .signAndSend(SENDER, { signer: injector.signer }, (status) => {
    console.log(status.txHash);
  });

// unsubscribe
unsub();