How can you transfer SOL using the web3.js sdk for Solana?

Question

How can you transfer SOL using the web3.js sdk for Solana?

Answer 1

var web3 = require("@solana/web3.js");
// Address: 9vpsmXhZYMpvhCKiVoX5U8b1iKpfwJaFpPEEXF7hRm9N
const DEMO_FROM_SECRET_KEY = new Uint8Array([
    37, 21, 197, 185, 105, 201, 212, 148, 164, 108, 251, 159, 174, 252, 43, 246,
    225, 156, 38, 203, 99, 42, 244, 73, 252, 143, 34, 239, 15, 222, 217, 91, 132,
    167, 105, 60, 17, 211, 120, 243, 197, 99, 113, 34, 76, 127, 190, 18, 91, 246,
    121, 93, 189, 55, 165, 129, 196, 104, 25, 157, 209, 168, 165, 149,
]);
(async () => {
    // Connect to cluster
    var connection = new web3.Connection(web3.clusterApiUrl("devnet"));
    // Construct a `Keypair` from secret key
    var from = web3.Keypair.fromSecretKey(DEMO_FROM_SECRET_KEY);
    // Generate a new random public key
    var to = web3.Keypair.generate();
    // Add transfer instruction to transaction
    var transaction = new web3.Transaction().add(
        web3.SystemProgram.transfer({
            fromPubkey: from.publicKey,
            toPubkey: to.publicKey,
            lamports: web3.LAMPORTS_PER_SOL / 100,
        })
    );
    // Sign transaction, broadcast, and confirm
    var signature = await web3.sendAndConfirmTransaction(
        connection,
        transaction,
        [from]
    );
    console.log("SIGNATURE", signature);
    console.log("SUCCESS");
})();

Answer 2

Here's an example of how you can do that. Assumptions:

1. You have a Phantom wallet.
2. You're working on devnet
3. You have a string of the public key (address) of the destination wallet. "9fuYBoRvgptU4fVZ8ZqvWTTc6oC68P4tjuSA2ySzn6Nv" would be used here.

Code

  import * as web3 from '@solana/web3.js';
  import * as splToken from '@solana/spl-token';
  
  const getProvider = async () => {
    if ("solana" in window) {
      const provider = window.solana;
      if (provider.isPhantom) {
        console.log("Is Phantom installed?  ", provider.isPhantom);
        return provider;
      }
    } else {
      window.open("https://www.phantom.app/", "_blank");
    }
  };


  async function transferSOL() {
    // Detecing and storing the phantom wallet of the user (creator in this case)
    var provider = await getProvider();
    console.log("Public key of the emitter: ",provider.publicKey.toString());

    // Establishing connection
    var connection = new web3.Connection(
      web3.clusterApiUrl('devnet'),
    );

    // I have hardcoded my secondary wallet address here. You can take this address either from user input or your DB or wherever
    var recieverWallet = new web3.PublicKey("9fuYBoRvgptU4fVZ8ZqvWTTc6oC68P4tjuSA2ySzn6Nv");

    // Airdrop some SOL to the sender's wallet, so that it can handle the txn fee
    var airdropSignature = await connection.requestAirdrop(
      provider.publicKey,
      web3.LAMPORTS_PER_SOL,
    );

    // Confirming that the airdrop went through
    await connection.confirmTransaction(airdropSignature);
    console.log("Airdropped");

    var transaction = new web3.Transaction().add(
      web3.SystemProgram.transfer({
        fromPubkey: provider.publicKey,
        toPubkey: recieverWallet,
        lamports: web3.LAMPORTS_PER_SOL //Investing 1 SOL. Remember 1 Lamport = 10^-9 SOL.
      }),
    );

    // Setting the variables for the transaction
    transaction.feePayer = await provider.publicKey;
    let blockhashObj = await connection.getRecentBlockhash();
    transaction.recentBlockhash = await blockhashObj.blockhash;

    // Transaction constructor initialized successfully
    if(transaction) {
      console.log("Txn created successfully");
    }
    
    // Request creator to sign the transaction (allow the transaction)
    let signed = await provider.signTransaction(transaction);
    // The signature is generated
    let signature = await connection.sendRawTransaction(signed.serialize());
    // Confirm whether the transaction went through or not
    await connection.confirmTransaction(signature);

    //Print the signature here
    console.log("Signature: ", signature);
  }