XRP Ledger Apex is back in Amsterdam

Register Now
Documentation
/
Tutorials
/
JavaScript
/
NFTs Using JavaScript
/
Transfer NFTs Using JavaScript
Last updated
Edit

Transfer NFTs Using JavaScript

This example shows how to:

  1. Create NFT Sell Offers.
  2. Create NFT Buy Offers.
  3. Accept NFT Sell Offers.
  4. Accept NFT Buy Offers.
  5. Get a list of offers for a particular NFT.
  6. Cancel an offer.

Quickstart form with NFT transfer fields

You can download the Quickstart Samples archive to try each of the samples in your own browser.

Usage

Get Accounts

  1. Open 4.transfer-nfts.html in a browser.
  2. Choose your ledger instance (Testnet or Devnet).
  3. Get test accounts.
    1. If you have existing test account seeds
      1. Paste account seeds in the Seeds field.
      2. Click Get Accounts from Seeds.
    2. If you do not have test account seeds:
      1. Click Get New Standby Account.
      2. Click Get New Operational Account.

Form with account information

Create a Sell Offer

To create a NFT sell offer:

  1. Enter the Amount of the sell offer in drops (millionths of an XRP).
  2. Set the Flags field to 1.
  3. Enter the NFT ID of the NFT you want to sell.
  4. Optionally, enter a number of days until Expiration.
  5. Click Create Sell Offer.

The important piece of information in the response is the NFT Offer Index, labeled as nft_offer_index, which you use to accept the sell offer.

NFT Sell Offer

Accept Sell Offer

Once a sell offer is available, another account can opt to accept the offer and buy the NFT.

To accept an available sell offer:

  1. Enter the NFT Offer Index (labeled as nft_offer_index in the token offer results. This is different from the NFTokenID.)
  2. Click Accept Sell Offer.

Accept Sell Offer

Create a Buy Offer

You can offer to buy a NFT from another account.

To create an offer to buy a NFT:

  1. Enter the Amount of your offer.
  2. Enter the NFT ID.
  3. Enter the owner’s account string in the Owner field.
  4. Optionally enter the number of days until Expiration.
  5. Click Create Buy Offer.

NFT Buy Offer

Accept a Buy Offer

To accept an offer to buy a NFT:

  1. Enter the NFT Offer Index (the nft_offer_index of the NFT buy offer).
  2. Click Accept Buy Offer.

Accept Buy Offer

Get Offers

To list the buy and sell offers associated with a NFT:

  1. Enter the NFT ID.
  2. Click Get Offers.

Get offers

Cancel Offer

To cancel a buy or sell offer that you have created:

  1. Enter the NFT Offer Index.
  2. Click Cancel Offer.

Cancel offer

Code Walkthrough

You can download the Quickstart Samples archive to try each of the samples in your own browser.

Create Sell Offer

// *******************************************************
// ****************** Create Sell Offer ******************
// *******************************************************
      
async function createSellOffer() {

Connect to the ledger and get the accounts.

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  standbyResultField.value = results
  await client.connect()
  results += '\nConnected. Creating sell offer...'
  standbyResultField.value = results

Compute the Expiration Date, if present. The expiration date represents the number of seconds after the Ripple Epoch that the offer should expire. Start with the current date, add the number of days till expiration, then set the expirationDate variable to the converted date in Ripple time.

  var expirationDate = null
  if (standbyExpirationField.value !="") {
    var days = standbyExpirationField.value
    let d = new Date()
    d.setDate(d.getDate() + parseInt(days))
    var expirationDate = xrpl.isoTimeToRippleTime(d)
  }

Define the transaction. A Flags value of 1 indicates that this transaction is a sell offer.

  let transactionBlob = {
    "TransactionType": "NFTokenCreateOffer",
    "Account": standby_wallet.classicAddress,
    "NFTokenID": standbyTokenIdField.value,
    "Amount": standbyAmountField.value,
    "Flags": parseInt(standbyFlagsField.value),
  }

If the Expiration Date is present, append it to the transaction.

  if (expirationDate != null) {
    transactionBlob.Expiration = expirationDate
  }

If the Destination field is not empty, append it to the transaction. When the destination is set, only the destination account can buy the NFToken.

  if(standbyDestinationField.value !== '') {
    transactionBlob.Destination = standbyDestinationField.value
  }

Submit the transaction and wait for the results.

  const tx = await client.submitAndWait(transactionBlob,{wallet: standby_wallet})
  results += '\n\n***Sell Offers***\n'

Request the list of sell offers for the token.

  let nftSellOffers
  try {
    nftSellOffers = await client.request({
      method: "nft_sell_offers",
      nft_id: standbyTokenIdField.value})
  } catch (err) {
    nftSellOffers = "No sell offers."
  }
  results += JSON.stringify(nftSellOffers,null,2)

Request the list of buy offers for the token.

  results += '\n\n***Buy Offers***\n'
  let nftBuyOffers
  try {
    nftBuyOffers = await client.request({
      method: "nft_buy_offers",
      nft_id: standbyTokenIdField.value })
      results += JSON.stringify(nftBuyOffers,null,2)
  } catch (err) {
    results += 'No buy offers.'
  }

Report the results of the transaction.

  results += '\n\nTransaction result:\n' + 
    JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += '\n\nBalance changes:\n' + 
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)

Get the current XRP balances for the operational and standby accounts.

  operationalBalanceField.value = (await client.getXrpBalance(operational_wallet.address))
  standbyBalanceField.value = (await client.getXrpBalance(standby_wallet.address))
  standbyResultField.value = results

Disconnect from the ledger.

  client.disconnect()
}// End of createSellOffer()

Create Buy Offer

// *******************************************************
// ***************** Create Buy Offer ********************
// *******************************************************

async function createBuyOffer() {

Get the account and connect to the ledger.

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  let results = 'Connecting to ' + net + '...'
  standbyResultField.value = results
  await client.connect()
  results = '\nConnected. Creating buy offer...'
  standbyResultField.value = results

Prepare the expiration date, if present.

  var expirationDate = null
  if (standbyExpirationField.value !="") {
    var days = standbyExpirationField.value
    let d = new Date()
    d.setDate(d.getDate() + parseInt(days))
    var expirationDate = xrpl.isoTimeToRippleTime(d)
  }

Define the transaction. Setting the Flags value to null indicates that this is a buy offer.

  const transactionBlob = {
    "TransactionType": "NFTokenCreateOffer",
    "Account": standby_wallet.classicAddress,
    "Owner": standbyOwnerField.value,
    "NFTokenID": standbyTokenIdField.value,
    "Amount": standbyAmountField.value,
    "Flags": null
  }

If the expiration date is present, append that to the transaction.

  if (expirationDate != null) {
    transactionBlob.Expiration = expirationDate
  }

Submit the transaction and wait for the results.

  const tx = await client.submitAndWait(transactionBlob,{wallet: standby_wallet})

Request the list of sell offers for the token.

  results += "\n\n***Sell Offers***\n"
  let nftSellOffers
  try {
    nftSellOffers = await client.request({
      method: "nft_sell_offers",
      nft_id: standbyTokenIdField.value })
  } catch (err) {
    nftSellOffers = "No sell offers."
  }
  results += JSON.stringify(nftSellOffers,null,2)

Request the list of buy offers for the token.

  results += "\n\n***Buy Offers***\n"
  let nftBuyOffers
  try {
    nftBuyOffers = await client.request({
    method: "nft_buy_offers",
    nft_id: standbyTokenIdField.value })
    results += JSON.stringify(nftBuyOffers,null,2)
  } catch (err) {
    results += "No buy offers."
  }

Report the results of the transaction.

  results += "\n\nTransaction result:\n" +
    JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += "\n\nBalance changes:\n" + 
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  standbyResultField.value = results```

Disconnect from the ledger.

```javascript      
  client.disconnect()
}// End of createBuyOffer()

Cancel Offer

// START HERE

// *******************************************************
// ******************** Cancel Offer *********************
// *******************************************************

async function cancelOffer() {

Get the standby address and connect to the ledger.

  const wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...' + standbyResultField.value = results
  await client.connect()
  results +=  "\nConnected. Cancelling offer..."
  standbyResultField.value = results

Insert the token offer index as a new array. This example destroys one offer at a time. In practice you could implement the function to accept multiple token offer index values and destroy all of the token offers in one operation.

  const tokenOfferIDs = [standbyTokenOfferIndexField.value]

Define the transaction.

  const transactionBlob = {
    "TransactionType": "NFTokenCancelOffer",
    "Account": wallet.classicAddress,
    "NFTokenOffers": tokenOfferIDs
  }

Submit the transaction and wait for the results.

  const tx = await client.submitAndWait(transactionBlob,{wallet})

Request the list of sell offers for the token.

  results += "\n\n***Sell Offers***\n"
  let nftSellOffers
  try {
    nftSellOffers = await client.request({
      method: "nft_sell_offers",
      nft_id: standbyTokenIdField.value
    })
  } catch (err) {
    nftSellOffers = "No sell offers."
  }
  results += JSON.stringify(nftSellOffers,null,2)

Request the list of buy offers for the token.

  results += "\n\n***Buy Offers***\n"
  let nftBuyOffers
  try {
    nftBuyOffers = await client.request({
      method: "nft_buy_offers",
      nft_id: standbyTokenIdField.value
    })
    results += JSON.stringify(nftBuyOffers,null,2)
  } catch (err) {
    nftBuyOffers = "No buy offers."
  }

Report the transaction results.

  results += "\nTransaction result:\n" +
    JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += "\nBalance changes:\n" + 
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  standbyResultField.value = results

Disconnect from the ledger.

  client.disconnect() // End of cancelOffer()
}

Get Offers

// *******************************************************
// ******************** Get Offers ***********************
// *******************************************************


async function getOffers() {

Connect to the ledger.

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  standbyResultField.value = results
  await client.connect()
  results += '\nConnected. Getting offers...'
  standbyResultField.value = results

Request the list of sell offers for the token.

  results += '\n\n***Sell Offers***\n'
  let nftSellOffers
  try {
    nftSellOffers = await client.request({
      method: "nft_sell_offers",
      nft_id: standbyTokenIdField.value
    })
  } catch (err) {
      nftSellOffers = 'No sell offers.'
  }
  results += JSON.stringify(nftSellOffers,null,2)
  standbyResultField.value = results

Request the list of buy offers for the token.

  results += '\n\n***Buy Offers***\n'
  let nftBuyOffers
  try {
    nftBuyOffers = await client.request({
      method: "nft_buy_offers",
      nft_id: standbyTokenIdField.value 
    })
  } catch (err) {
    nftBuyOffers =  'No buy offers.'
  }
  results += JSON.stringify(nftBuyOffers,null,2)
  standbyResultField.value = results

Disconnect from the ledger.

  client.disconnect()
}// End of getOffers()

Accept Sell Offer

// *******************************************************
// ****************** Accept Sell Offer ******************
// *******************************************************


async function acceptSellOffer() {

Get the accounts and connect to the ledger.

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  standbyResultField.value = results
  await client.connect()
  results += '\nConnected. Accepting sell offer...\n\n'
  standbyResultField.value = results

Define the transaction.

  const transactionBlob = {
    "TransactionType": "NFTokenAcceptOffer",
    "Account": standby_wallet.classicAddress,
    "NFTokenSellOffer": standbyTokenOfferIndexField.value,
  }

Submit the transaction and wait for the results.

  const tx = await client.submitAndWait(transactionBlob,{wallet: standby_wallet})

Request the list of NFTs for the standby account.

  const nfts = await client.request({
    method: "account_nfts",
    account: standby_wallet.classicAddress
  })

Get the balances for both accounts.

  standbyBalanceField.value = (await client.getXrpBalance(standby_wallet.address))
  operationalBalanceField.value = (await client.getXrpBalance(operational_wallet.address))

Report the transaction results.

  results += 'Transaction result:\n'
  results +=  JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += '\nBalance changes:'
  results +=  JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  results += JSON.stringify(nfts,null,2)
  standbyResultField.value = results

Disconnect from the ledger.

  client.disconnect()
}// End of acceptSellOffer()

Accept Buy Offer

// *******************************************************
// ******************* Accept Buy Offer ******************
// *******************************************************


async function acceptBuyOffer() {

Get the accounts and connect to the ledger.

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  standbyResultField.value = results
  await client.connect()
  results += '\nConnected. Accepting buy offer...'
  standbyResultField.value = results

Prepare the transaction.

  const transactionBlob = {
    "TransactionType": "NFTokenAcceptOffer",
    "Account": standby_wallet.classicAddress,
    "NFTokenBuyOffer": standbyTokenOfferIndexField.value
  }

Submit the transaction and wait for the results.

  const tx = await client.submitAndWait(transactionBlob,{wallet: standby_wallet})

Request the current list of NFTs for the standby account.

  const nfts = await client.request({
    method: "account_nfts",
    account: standby_wallet.classicAddress  
  })
  results += JSON.stringify(nfts,null,2)
  standbyResultField.value = results

Report the transaction result.

  results += "\n\nTransaction result:\n" + 
    JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += "\nBalance changes:\n" +
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)

Request the XRP balance for both accounts.

  operationalBalanceField.value = 
    (await client.getXrpBalance(operational_wallet.address))
  standbyBalanceField.value = 
    (await client.getXrpBalance(standby_wallet.address))
  standbyResultField.value = results

Disconnect from the ledger.

  client.disconnect()
}// End of acceptBuyOffer()

Reciprocal Transactions

These functions duplicate the functions of the standby account for the operational account. See the corresponding standby account function for walkthrough information.

// *******************************************************
// *********** Operational Create Sell Offer *************
// *******************************************************

async function oPcreateSellOffer() {
  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  operationalResultField.value = results
    await client.connect()
  results += '\nConnected. Creating sell offer...'
  operationalResultField.value = results

  //------------------------------------- Prepare Expiration Date
  var expirationDate = null
  if (operationalExpirationField.value !="") {
    var days = operationalExpirationField.value
    let d = new Date()
    d.setDate(d.getDate() + parseInt(days))
    var expirationDate = xrpl.isoTimeToRippleTime(d)
  }
  // Prepare transaction -------------------------------------------------------
  let transactionBlob = {
      "TransactionType": "NFTokenCreateOffer",
      "Account": operational_wallet.classicAddress,
      "NFTokenID": operationalTokenIdField.value,
      "Amount": operationalAmountField.value,
      "Flags": parseInt(operationalFlagsField.value),
  }
  if (expirationDate != null) {
    transactionBlob.Expiration = expirationDate
  }
  if(standbyDestinationField.value !== '') {
    transactionBlob.Destination = operationalDestinationField.value
  }

  // Submit transaction --------------------------------------------------------

  const tx = await client.submitAndWait(transactionBlob,{wallet: operational_wallet})

  results += '\n\n***Sell Offers***\n'

  let nftSellOffers
  try {
    nftSellOffers = await client.request({
      method: "nft_sell_offers",
      nft_id: operationalTokenIdField.value  
    })
  } catch (err) {
    nftSellOffers = "No sell offers."
  }
  results += JSON.stringify(nftSellOffers,null,2)
  results += '\n\n***Buy Offers***\n'
  let nftBuyOffers
  try {
    nftBuyOffers = await client.request({
      method: "nft_buy_offers",
      nft_id: operationalTokenIdField.value
    })
    results += JSON.stringify(nftBuyOffers,null,2)
  } catch (err) {
    results += 'No buy offers.'
  }

  // Check transaction results -------------------------------------------------
  results += '\n\nTransaction result:\n' + 
    JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += '\n\nBalance changes:\n' + 
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  operationalBalanceField.value = 
    (await client.getXrpBalance(operational_wallet.address))
  standbyBalanceField.value = 
    (await client.getXrpBalance(standby_wallet.address))
  operationalResultField.value = results

  client.disconnect()
}  // End of oPcreateSellOffer()

// *******************************************************
// ************** Operational Create Buy Offer ***********
// *******************************************************

async function oPcreateBuyOffer() {

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  let results = 'Connecting to ' + net + '...'
  operationalResultField.value = results
  await client.connect()
  results = '\nConnected. Creating buy offer...'
  operationalResultField.value = results

  //------------------------------------- Prepare Expiration Date
  var expirationDate = null
  if (operationalExpirationField.value !="") {
    var days = operationalExpirationField.value
    let d = new Date()
    d.setDate(d.getDate() + parseInt(days))
    var expirationDate = xrpl.isoTimeToRippleTime(d)
  }

  // Prepare transaction -------------------------------------------------------
  const transactionBlob = {
    "TransactionType": "NFTokenCreateOffer",
    "Account": operational_wallet.classicAddress,
    "Owner": operationalOwnerField.value,
    "NFTokenID": operationalTokenIdField.value,
    "Amount": operationalAmountField.value,
    "Flags": null,
  }
  if (expirationDate != null) {
    transactionBlob.Expiration = expirationDate
  }
  // Submit transaction --------------------------------------------------------
  const tx = await client.submitAndWait(transactionBlob,{wallet: operational_wallet})

  results += "\n\n***Sell Offers***\n"
  let nftSellOffers
  try {
    nftSellOffers = await client.request({
      method: "nft_sell_offers",
      nft_id: operationalTokenIdField.value  
    })
  } catch (err) {
    nftSellOffers = "No sell offers."
  }
  results += JSON.stringify(nftSellOffers,null,2)
  results += "\n\n***Buy Offers***\n"
  let nftBuyOffers
  try {
    nftBuyOffers = await client.request({
      method: "nft_buy_offers",
      nft_id: operationalTokenIdField.value
    })
  } catch (err) {
    results += "No buy offers."
  }
  results += JSON.stringify(nftBuyOffers,null,2)

  // Check transaction results -------------------------------------------------
  results += "\n\nTransaction result:\n" +
    JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += "\n\nBalance changes:\n" + 
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  operationalResultField.value = results

  client.disconnect()
}// End of oPcreateBuyOffer()

// *******************************************************
// ************* Operational Cancel Offer ****************
// *******************************************************

async function oPcancelOffer() {

  const wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  operationalResultField.value = results
  await client.connect()
  results +=  "\nConnected. Cancelling offer..."
  operationalResultField.value = results

  const tokenOfferIDs = [operationalTokenOfferIndexField.value]

  // Prepare transaction -------------------------------------------------------
  const transactionBlob = {
    "TransactionType": "NFTokenCancelOffer",
    "Account": wallet.classicAddress,
    "NFTokenOffers": tokenOfferIDs
  }
  // Submit transaction --------------------------------------------------------
  const tx = await client.submitAndWait(transactionBlob,{wallet})

  results += "\n\n***Sell Offers***\n"
  let nftSellOffers
  try {
    nftSellOffers = await client.request({
      method: "nft_sell_offers",
      nft_id: operationalTokenIdField.value
    })
  } catch (err) {
    nftSellOffers = "No sell offers."
  }
  results += JSON.stringify(nftSellOffers,null,2)
  results += "\n\n***Buy Offers***\n"
  let nftBuyOffers
  try {
    nftBuyOffers = await client.request({
      method: "nft_buy_offers",
      nft_id: operationalTokenIdField.value
    })
  } catch (err) {
    nftBuyOffers = "No buy offers."
  }
  results += JSON.stringify(nftBuyOffers,null,2)

  // Check transaction results -------------------------------------------------

  results += "\nTransaction result:\n" +
    JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += "\nBalance changes:\n" + 
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  operationalResultField.value = results

  client.disconnect()
}// End of oPcancelOffer()

// *******************************************************
// **************** Operational Get Offers ***************
// *******************************************************

async function oPgetOffers() {
//  const standby_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  operationalResultField.value = results
  await client.connect()
  results += '\nConnected. Getting offers...'

  results += '\n\n***Sell Offers***\n'

  let nftSellOffers
  try {
    nftSellOffers = await client.request({
      method: "nft_sell_offers",
      nft_id: operationalTokenIdField.value
    })
  } catch (err) {
    nftSellOffers = 'No sell offers.'
  }
  results += JSON.stringify(nftSellOffers,null,2)

  results += '\n\n***Buy Offers***\n'
  let nftBuyOffers
  try {
    nftBuyOffers = await client.request({
      method: "nft_buy_offers",
      nft_id: operationalTokenIdField.value
    })
  } catch (err) {
    nftBuyOffers =  'No buy offers.'
  }
  results += JSON.stringify(nftBuyOffers,null,2)  
  operationalResultField.value = results

  client.disconnect()
}// End of oPgetOffers()

// *******************************************************
// *************** Operational Accept Sell Offer *********
// *******************************************************

async function oPacceptSellOffer() {
  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  operationalResultField.value = results
  await client.connect()
  results += '\nConnected. Accepting sell offer...\n\n'
  operationalResultField.value = results

  // Prepare transaction -------------------------------------------------------
  const transactionBlob = {
    "TransactionType": "NFTokenAcceptOffer",
    "Account": operational_wallet.classicAddress,
    "NFTokenSellOffer": operationalTokenOfferIndexField.value,
  }
  // Submit transaction --------------------------------------------------------
  const tx = await client.submitAndWait(transactionBlob,{wallet: operational_wallet}) 
  const nfts = await client.request({
    method: "account_nfts",
    account: operational_wallet.classicAddress
  })

  // Check transaction results -------------------------------------------------

  standbyBalanceField.value = (await client.getXrpBalance(standby_wallet.address))
  operationalBalanceField.value = (await client.getXrpBalance(operational_wallet.address))

  results += 'Transaction result:\n'
  results +=  JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += '\nBalance changes:'
  results +=  JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  results += JSON.stringify(nfts,null,2)   
  operationalResultField.value = results    
  client.disconnect()
}// End of acceptSellOffer()

// *******************************************************
// ********* Operational Accept Buy Offer ****************
// *******************************************************

async function oPacceptBuyOffer() {
  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + net + '...'
  operationalResultField.value = results
  await client.connect()
  results += '\nConnected. Accepting buy offer...'
  operationalResultField.value = results

  // Prepare transaction -------------------------------------------------------
  const transactionBlob = {
    "TransactionType": "NFTokenAcceptOffer",
    "Account": operational_wallet.classicAddress,
    "NFTokenBuyOffer": operationalTokenOfferIndexField.value
  }
  // Submit transaction --------------------------------------------------------
  const tx = await client.submitAndWait(transactionBlob,{wallet: operational_wallet}) 
  const nfts = await client.request({
    method: "account_nfts",
    account: operational_wallet.classicAddress
  })
  results += JSON.stringify(nfts,null,2)
  operationalResultField.value = results

  // Check transaction results -------------------------------------------------
  results += "\n\nTransaction result:\n" + 
    JSON.stringify(tx.result.meta.TransactionResult, null, 2)
  results += "\nBalance changes:\n" +
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  operationalBalanceField.value = 
    (await client.getXrpBalance(operational_wallet.address))
  operationalBalanceField.value = 
    (await client.getXrpBalance(standby_wallet.address))
  operationalResultField.value = results
  client.disconnect()
}// End of acceptBuyOffer()

4.transfer-nfts.html

Update the form with fields and buttons to support the new functions.

<html>
  <head>
    <title>Token Test Harness</title>
    <link href='https://fonts.googleapis.com/css?family=Work Sans' rel='stylesheet'>
    <style>
       body{font-family: "Work Sans", sans-serif;padding: 20px;background: #fafafa;}
       h1{font-weight: bold;}
       input, button {padding: 6px;margin-bottom: 8px;}
       button{font-weight: bold;font-family: "Work Sans", sans-serif;}
       td{vertical-align: middle;}
    </style>
    <script src='https://unpkg.com/[email protected]/build/xrpl-latest-min.js'></script>
    <script src='ripplex1-send-xrp.js'></script>
    <script src='ripplex2-send-currency.js'></script>
    <script src='ripplex3-mint-nfts.js'></script>
    <script src='ripplex4-transfer-nfts.js'></script>
    <script>
      if (typeof module !== "undefined") {
        const xrpl = require('xrpl')
      }
     
    </script>
  </head>
  
<!-- ************************************************************** -->
<!-- ********************** The Form ****************************** -->
<!-- ************************************************************** -->

  <body>
    <h1>Token Test Harness</h1>
    <form id="theForm">
      Choose your ledger instance:
      &nbsp;&nbsp;
      <input type="radio" id="tn" name="server"
        value="wss://s.altnet.rippletest.net:51233" checked>
      <label for="testnet">Testnet</label>
      &nbsp;&nbsp;
      <input type="radio" id="dn" name="server"
        value="wss://s.devnet.rippletest.net:51233">
      <label for="devnet">Devnet</label>
      <br/><br/>
      <button type="button" onClick="getAccountsFromSeeds()">Get Accounts From Seeds</button>
      <br/>
      <textarea id="seeds" cols="40" rows= "2"></textarea>
      <br/><br/>
      <table>
        <tr valign="top">
          <td>
            <table>
              <tr valign="top">
                <td>
                <td>
                  <button type="button" onClick="getAccount('standby')">Get New Standby Account</button>
                  <table>
                    <tr valign="top">
                      <td align="right">
                        Standby Account
                      </td>
                      <td>
                        <input type="text" id="standbyAccountField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Public Key
                      </td>
                      <td>
                        <input type="text" id="standbyPubKeyField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Private Key
                      </td>
                      <td>
                        <input type="text" id="standbyPrivKeyField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Seed
                      </td>
                      <td>
                        <input type="text" id="standbySeedField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        XRP Balance
                      </td>
                      <td>
                        <input type="text" id="standbyBalanceField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Amount
                      </td>
                      <td>
                        <input type="text" id="standbyAmountField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr valign="top">
                      <td><button type="button" onClick="configureAccount('standby',document.querySelector('#standbyDefault').checked)">Configure Account</button></td>
                      <td>
                        <input type="checkbox" id="standbyDefault" checked="true"/>
                        <label for="standbyDefault">Allow Rippling</label>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Currency
                      </td>
                      <td>
                        <input type="text" id="standbyCurrencyField" size="40" value="USD"></input>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">NFT URL</td>
                      <td><input type="text" id="standbyTokenUrlField"
                        value = "ipfs://bafybeigdyrzt5sfp7udm7hu76uh7y26nf4dfuylqabf3oclgtqy55fbzdi" size="80"/>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">Flags</td>
                      <td><input type="text" id="standbyFlagsField" value="1" size="10"/></td>
                    </tr>
                    <tr>
                      <td align="right">NFT ID</td>
                      <td><input type="text" id="standbyTokenIdField" value="" size="80"/></td>
                    </tr>
                    <tr>
                      <td align="right">NFT Offer Index</td>
                      <td><input type="text" id="standbyTokenOfferIndexField" value="" size="80"/></td>
                    </tr>
                    <tr>
                      <td align="right">Owner</td>
                      <td><input type="text" id="standbyOwnerField" value="" size="80"/></td>
                    </tr>
                    <tr>
                      <td align="right">Destination</td>
                      <td><input type="text" id="standbyDestinationField" value="" size="80"/></td>
                    </tr>
                    <tr>
                      <td align="right">Expiration</td>
                      <td><input type="text" id="standbyExpirationField" value="" size="80"/></td>
                    </tr>
                    <tr>
                      <td align="right">Transfer Fee</td>
                      <td><input type="text" id="standbyTransferFeeField" value="" size="80"/></td>
                    </tr>
                  </table>
                  <p align="left">
                    <textarea id="standbyResultField" cols="80" rows="20" ></textarea>
                  </p>
                </td>
                </td>
                <td>
                  <table>
                    <tr valign="top">
                      <td align="center" valign="top">
                        <button type="button" onClick="sendXRP()">Send XRP&#62;</button>
                        <br/><br/>
                        <button type="button" onClick="createTrustline()">Create TrustLine</button>
                        <br/>
                        <button type="button" onClick="sendCurrency()">Send Currency</button>
                        <br/>
                        <button type="button" onClick="getBalances()">Get Balances</button>
                        <br/><br/>
                        <button type="button" onClick="mintToken()">Mint NFT</button>
                        <br/>
                        <button type="button" onClick="getTokens()">Get NFTs</button>
                        <br/>
                        <button type="button" onClick="burnToken()">Burn NFT</button>
                        <br/><br/>
                        <button type="button" onClick="createSellOffer()">Create Sell Offer</button>
                        <br/>
                        <button type="button" onClick="acceptSellOffer()">Accept Sell Offer</button>
                        <br/>
                        <button type="button" onClick="createBuyOffer()">Create Buy Offer</button>
                        <br/>
                        <button type="button" onClick="acceptBuyOffer()">Accept Buy Offer</button>
                        <br/>
                        <button type="button" onClick="getOffers()">Get Offers</button>
                        <br/>
                        <button type="button" onClick="cancelOffer()">Cancel Offer</button>
                      </td>
                    </tr>
                    </td>
                    </tr>
                  </table>
                </td>
              </tr>
            </table>
          </td>
          <td>
            <table>
              <tr>
                <td>
                <td>
                  <table>
                    <tr>
                      <td align="center" valign="top">
                        <button type="button" onClick="oPsendXRP()">&#60; Send XRP</button>
                        <br/><br/>
                        <button type="button" onClick="oPcreateTrustline()">Create TrustLine</button>
                        <br/>
                        <button type="button" onClick="oPsendCurrency()">Send Currency</button>
                        <br/>
                        <button type="button" onClick="getBalances()">Get Balances</button>
                        <br/><br/>
                        <button type="button" onClick="oPmintToken()">Mint NFT</button>
                        <br/>
                        <button type="button" onClick="oPgetTokens()">Get NFTs</button>
                        <br/>
                        <button type="button" onClick="oPburnToken()">Burn NFT</button>
                        <br/><br/>
                        <button type="button" onClick="oPcreateSellOffer()">Create Sell Offer</button>
                        <br/>
                        <button type="button" onClick="oPacceptSellOffer()">Accept Sell Offer</button>
                        <br/>
                        <button type="button" onClick="oPcreateBuyOffer()">Create Buy Offer</button>
                        <br/>
                        <button type="button" onClick="oPacceptBuyOffer()">Accept Buy Offer</button>
                        <br/>
                        <button type="button" onClick="oPgetOffers()">Get Offers</button>
                        <br/>
                        <button type="button" onClick="oPcancelOffer()">Cancel Offer</button>
                      </td>
                      <td valign="top" align="right">
                        <button type="button" onClick="getAccount('operational')">Get New Operational Account</button>
                        <table>
                          <tr valign="top">
                            <td align="right">
                              Operational Account
                            </td>
                            <td>
                              <input type="text" id="operationalAccountField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Public Key
                            </td>
                            <td>
                              <input type="text" id="operationalPubKeyField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Private Key
                            </td>
                            <td>
                              <input type="text" id="operationalPrivKeyField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Seed
                            </td>
                            <td>
                              <input type="text" id="operationalSeedField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              XRP Balance
                            </td>
                            <td>
                              <input type="text" id="operationalBalanceField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Amount
                            </td>
                            <td>
                              <input type="text" id="operationalAmountField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td>
                            </td>
                            <td align="right">                        <input type="checkbox" id="operationalDefault" checked="true"/>
                              <label for="operationalDefault">Allow Rippling</label>
                              <button type="button" onClick="configureAccount('operational',document.querySelector('#operationalDefault').checked)">Configure Account</button>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Currency
                            </td>
                            <td>
                              <input type="text" id="operationalCurrencyField" size="40" value="USD"></input>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">NFT URL</td>
                            <td><input type="text" id="operationalTokenUrlField"
                              value = "ipfs://bafybeigdyrzt5sfp7udm7hu76uh7y26nf4dfuylqabf3oclgtqy55fbzdi" size="80"/>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">Flags</td>
                            <td><input type="text" id="operationalFlagsField" value="1" size="10"/></td>
                          </tr>
                          <tr>
                            <td align="right">NFT ID</td>
                            <td><input type="text" id="operationalTokenIdField" value="" size="80"/></td>
                          </tr>
                          <tr>
                            <td align="right">NFT Offer Index</td>
                            <td><input type="text" id="operationalTokenOfferIndexField" value="" size="80"/></td>
                          </tr>
                          <tr>
                            <td align="right">Owner</td>
                            <td><input type="text" id="operationalOwnerField" value="" size="80"/></td>
                          </tr>
                          <tr>
                            <td align="right">Destination</td>
                            <td><input type="text" id="operationalDestinationField" value="" size="80"/></td>
                          </tr>
                          <tr>
                            <td align="right">Expiration</td>
                            <td><input type="text" id="operationalExpirationField" value="" size="80"/></td>
                          </tr>
                          <tr>
                            <td align="right">Transfer Fee</td>
                            <td><input type="text" id="operationalTransferFeeField" value="" size="80"/></td>
                          </tr>
                        </table>
                        <p align="right">
                          <textarea id="operationalResultField" cols="80" rows="20" ></textarea>
                        </p>
                      </td>
                      </td>
                    </tr>
                    </td>
                    </tr>
                  </table>
                </td>
              </tr>
            </table>
          </td>
        </tr>
      </table>
    </form>
  </body>
</html>