sol_change_example.ts

import {
  LAMPORTS_PER_SOL,
  SystemProgram,
  Transaction,
  sendAndConfirmTransaction,
  Keypair,
} from "@solana/web3.js";

// Use Playground cluster connection
const connection = pg.connection;

// Use Playground wallet as sender, generate random keypair as receiver
const sender = pg.wallet.keypair;
const receiver = new Keypair();

// Check and log balance before transfer
const preBalance1 = await connection.getBalance(sender.publicKey);
const preBalance2 = await connection.getBalance(receiver.publicKey);

console.log("sender prebalance:", preBalance1 / LAMPORTS_PER_SOL);
console.log("receiver prebalance:", preBalance2 / LAMPORTS_PER_SOL);
console.log("\n");

// Define the amount to transfer
const transferAmount = 0.01; // 0.01 SOL

// Create a transfer instruction for transferring SOL from wallet_1 to wallet_2
const transferInstruction = SystemProgram.transfer({
  fromPubkey: sender.publicKey,
  toPubkey: receiver.publicKey,
  lamports: transferAmount * LAMPORTS_PER_SOL, // Convert transferAmount to lamports
});

// Add the transfer instruction to a new transaction
const transaction = new Transaction().add(transferInstruction);

(async () => {
  const publicKey = receiver.publicKey;
  connection.onAccountChange(
    publicKey,
    (updatedAccountInfo, context) =>
      console.log("Updated account info: ", updatedAccountInfo),
    "confirmed"
  );
})();

// Send the transaction to the network
const transactionSignature = await sendAndConfirmTransaction(
  connection,
  transaction,
  [sender] // signer
);

// Check and log balance after transfer
const postBalance1 = await connection.getBalance(sender.publicKey);
const postBalance2 = await connection.getBalance(receiver.publicKey);

console.log("sender postbalance:", postBalance1 / LAMPORTS_PER_SOL);
console.log("receiver postbalance:", postBalance2 / LAMPORTS_PER_SOL);
console.log("\n");

console.log(
  "Transaction Signature:",
  `https://explorer.solana.com/tx/${transactionSignature}?cluster=devnet`
);