# 2.2 Creating Cross-Chain Transactions Using API #### 2.2.1 EVM Compatible Chains The transaction generation API allows the server to quickly fill in cross-chain parameters and return cross-chain transaction data that is ready for user signing. [`https://bridge-api.wanchain.org/api/createTx`](https://bridge-api.wanchain.org/api/createTx) **Example:** ```bash curl -X POST -H "Content-Type: application/json" --data '{"fromChain":"OETH", "toChain":"ETH", "fromToken":"0x0000000000000000000000000000000000000000", "toToken":"0x0000000000000000000000000000000000000000", "toAccount":"0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "amount": "0.01"}' ``` **Parameter explanation:** Use the HTTP POST method and provide the following JSON payload: ```json { "fromChain": "OETH", "toChain": "ETH", "fromToken": "0x0000000000000000000000000000000000000000", "toToken": "0x0000000000000000000000000000000000000000", "fromAccount": "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "toAccount": "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "amount": "0.01" } ``` * **fromChain / toChain**: Specify either the `chainType` or `chainId` from the table below (do not mix them). * **fromToken / toToken**: Token contract address; use `0x0000000000000000000000000000000000000000` for native coins. * **toAccount**: Destination wallet address on the target chain. * **amount**: Amount to transfer, represented as a decimal string. **Supported Chains:** | Index | Chain Name | Chain Type | Chain ID | | ----- | ----------------- | ---------- | ---------- | | 1 | Bitcoin | BTC | 2147483648 | | 2 | Litecoin | LTC | 2147483650 | | 3 | Dogecoin | DOGE | 2147483651 | | 4 | Ethereum | ETH | 2147483708 | | 5 | XRPL | XRP | 2147483792 | | 6 | EOS | EOS | 2147483842 | | 7 | Tron | TRX | 2147483843 | | 8 | Polkadot | DOT | 2147484002 | | 9 | XinFin.Network | XDC | 2147484198 | | 10 | Optimism | OETH | 2147484262 | | 11 | BSC | BNB | 2147484362 | | 12 | Astar | ASTR | 2147484458 | | 13 | Polygon | MATIC | 2147484614 | | 14 | Telos | TLOS | 2147484625 | | 15 | OKT Chain | OKT | 2147484644 | | 16 | Fantom | FTM | 2147484655 | | 17 | Cardano | ADA | 2147485463 | | 18 | Avalanche C-Chain | AVAX | 2147492648 | | 19 | Energi | NRG | 2147493445 | | 20 | Wanchain | WAN | 2153201998 | | 21 | Bitrock | BROCK | 2154655314 | | 22 | Moonriver | MOVR | 1073741825 | | 23 | Arbitrum | ARETH | 1073741826 | | 24 | Moonbeam | GLMR | 1073741828 | | 25 | f(x)Core | FX | 1073741830 | | 26 | Gather | GTH | 1073741833 | | 27 | Metis | METIS | 1073741834 | | 28 | Songbird | SGB | 1073741836 | | 29 | zkSync Era | ZKETH | 1073741837 | | 30 | Horizen EON | ZEN | 1073741839 | | 31 | VinuChain | VC | 1073741840 | | 32 | BASE | BASEETH | 1073741841 | | 33 | Linea | LINEAETH | 1073741842 | **Response Example:** ```json { "success": true, "data": { "approveCheck": { "from": "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "token": "0xc2132d05d31c914a87c6611c10748aeb04b58e8f", "to": "0x2216072A246A84f7b9CE0f1415Dd239C9bF201aB", "amount": "10000" }, "tx": { "from": "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "to": "0x2216072A246A84f7b9CE0f1415Dd239C9bF201aB", "value": "0xde0b6b3a7640000", "data": "0x257011b6000000000000000000000000000000000000000000000041726965735f30333600000000000000000000000000000000000000000000000000000000000000bb0000000000000000000000000000000000000000000000000000000000002710000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000144cf0a877e906dead748a41ae7da8c220e4247d9e000000000000000000000000" }, "receiveAmount": "0.01", "chainId": 137, "txDataDetail": { "func": "userLock(bytes32,uint256,uint256,bytes)", "params": [ "0x000000000000000000000000000000000000000000000041726965735f303336", "187", "10000", "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e" ] }, "feeAndQuota": { "symbol": "USDT", "minQuota": "0", "maxQuota": "28543742384", "networkFee": { "value": "1000000000000000000", "isPercent": false }, "operationFee": { "value": "0", "isPercent": true } } } } ``` * If unsuccessful, `success: false`, and the reason for the error is returned. * The `tx` in the return value is the transaction body that can be used for wallet signing. Only the necessary parts are filled in, and the remaining parts can be automatically filled in by estimation on the chain. * If the `approveCheck` field exists, the ERC20 allowance must be checked first according to its contents. If the allowance is insufficient, an approve transaction needs to be sent first, followed by the tx. * `receiveAmount` is the expected amount of tokens to be received on the target chain. * `txDataDetail` is the detailed information of the packed transaction data field. * `feeAndQuota` is the details of the current cross-chain quota and fees, used for UI display. Moreover, **Partners can use the following API to record partner information for cross-chain initiations**: [`https://bridge-api.wanchain.org/api/createTx2`](https://bridge-api.wanchain.org/api/createTx2) You must fill in the partner's name within the body data. Below is an example JSON request: ```jsx { "fromChain": "ETH", "toChain": "BNB", "fromAccount": "0xdce713ec124daaeb25a458ef6dc51a5b48bcdbd8", "toAccount": "0xdce713ec124daaeb25a458ef6dc51a5b48bcdbd8", "amount": "100", "fromToken": "0xdac17f958d2ee523a2206206994597c13d831ec7", "toToken": "0x55d398326f99059ff775485246999027b3197955", "partner": "wanlend" } ``` The response data format is the same as the regular `createTx`. In the returned transaction, the `to` address is replaced with `crossWrapper` to record the cross-chain partner information. Currently, the chains that support recording partner information include: **WAN, ARETH, AVAX, ETH, MATIC, LINEAETH, PLYR, MOVR, GLMR, FTM, OETH, OKB, VC, ZEN, MATICETH, METIS, BLASTETH, XDC, FX, BASEETH, OPBNB, BNB, SGB.** * **Demo UI:** * **Demo UI Source Code:** **TRX Chain Transaction** Transactions from the TRX chain differ from those from EVM-compatible chains. Below is the API response format: ```json { "success": true, "data": { "approveCheck": { "from": "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "token": "41a614f803b6fd780986a42c78ec9c7f77e6ded13c", "to": "41fe464ebd5bb5d95731f90aa7b9e39df920a61c97", "amount": "10000" }, "tx": { "from": "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "to": "41fe464ebd5bb5d95731f90aa7b9e39df920a61c97", "abi": [ { "inputs": [ { "internalType": "bytes32", "name": "smgID", "type": "bytes32" }, { "internalType": "uint256", "name": "tokenPairID", "type": "uint256" }, { "internalType": "uint256", "name": "value", "type": "uint256" }, { "internalType": "bytes", "name": "userAccount", "type": "bytes" } ], "name": "userLock", "outputs": [], "stateMutability": "payable", "type": "function" } ], "functionSelector": "userLock(bytes32,uint256,uint256,bytes)", "rawParameter": "0x000000000000000000000000000000000000000000000041726965735f30333900000000000000000000000000000000000000000000000000000000000001110000000000000000000000000000000000000000000000000000000000002710000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000144cf0a877e906dead748a41ae7da8c220e4247d9e000000000000000000000000", "params": [ "0x000000000000000000000000000000000000000000000041726965735f303339", "273", "10000", "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e" ], "value": "0x13ab6680" }, "receiveAmount": "0.01", "feeAndQuota": { "symbol": "USDT", "minQuota": "1", "maxQuota": "953399472649", "networkFee": { "value": "330000000", "isPercent": false }, "operationFee": { "value": "0", "isPercent": false } } } } ``` The API response doesn't return the data for `tx`, but it returns ABI, smart contract (SC) address, function name and function params for TronLink to use. You can use the ABI and SC address to call the function by TronLink in your frontend code. Here is an exaple: ```jsx import { decodeFunctionData, parseAbi } from 'viem'; async function sendTronTx({ toAddr, functionSelector, callValue, data, // raw tx.data params, // arrays, function params }) { if (!window.tronWeb?.ready) { console.log('[TRON_TX] Requesting TronLink authorization...'); const res = await window.tronLink.request({ method: 'tron_requestAccounts' }); console.log('[TRON_TX] TronLink authorization result:', res); if (res.code !== 200) { throw new Error(`TronLink authorization failed: ${res.message}`); } } const isMobile = window.innerWidth <= 768; const abi = parseAbi(['function ' + functionSelector]); let decoded; if (data) { decoded = decodeFunctionData({ abi, data: data }); } else if (params) { decoded = {args: params}; } console.log('function args', abi, decoded.args); abi[0].stateMutability = "payable"; const sendParams = { feeLimit: 300_000_000, callValue: Number(callValue), shouldPollResponse: !isMobile, keepTxID: true, }; console.log('sendParams', sendParams); const contract = await window.tronWeb.contract(abi, toAddr); const result = await contract[functionSelector.split('(')[0]](...decoded.args).send( sendParams ); console.log('send tx', result); return result; } let txResult = await sendTronTx({ toAddr: tx.to, functionSelector: tx.functionSelector, callValue: tx.value, params: tx.params, }); console.log('tron tx result', txResult); let txHash = Array.isArray(txResult) ? txResult[0] : txResult; ``` #### 2.2.3 Bitcoin Chain Cross-chain API **2.2.3.1 Using Unisat Extension Wallet** (This method currently supports cross-chain transactions between EVM chains and Bitcoin.) **API endpoint:** * **Mainnet:** `https://bridge-api.wanchain.org/api/createTx2` * **Testnet:** `https://bridge-api.wanchain.org/api/testnet/createTx2` **Request Body Example:** ```json { "fromChain": "BTC", "toChain": "WAN", "fromAccount": "bc1qugvdunxxzqvy80hysz9y77nx50240n7ghhz3rd", "fromToken": "0x0000000000000000000000000000000000000000", "toToken": "0x50c439B6d602297252505a6799d84eA5928bCFb6", "toAccount": "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "amount": "0.001", "partner": "tester" } ``` **Response Example:** ```json { "success": true, "data": { "tx": { "fromAccount": "bc1qugvdunxxzqvy80hysz9y77nx50240n7ghhz3rd", "toAccount": "bc1pqnxalrglv6jglj9w9kg0dk9tyvkraw2xlj6cpzz8t3kxjl6pywesxqdfpg", "value": 100000, "memo": "01000f4cf0a877e906dead748a41ae7da8c220e4247d9e" }, "receiveAmount": "0.00064", "feeAndQuota": { "symbol": "BTC", "minQuota": "72000", "maxQuota": "100000000", "networkFee": { "value": "0", "isPercent": false }, "operationFee": { "value": "0.002", "isPercent": true, "minFeeLimit": "36000", "maxFeeLimit": "320000", "discountPercent": "1" } } } } ``` Sign the transaction using Unisat Wallet: ```tsx await (window as any).unisat.requestAccounts(); await (window as any).unisat.switchNetwork(isBtcTestnet ? 'testnet' : 'livenet'); const txData = result.data.tx; const tx = await (window as any).unisat.sendBitcoin(txData.toAccount, txData.value, { memo: txData.memo }); ``` **Demo UI:** \[`https://bridge-api-demo-ui.vercel.app/]()`
**2.2.3.2 Using One-Time Address** **Step 1: Generate a One-Time Address** **1) Send Request** * **Request Endpoint:** [`https://bridge-api.wanchain.org/api/createBtcOta`](https://bridge-api.wanchain.org/api/createBtcOta) * **Request Method:** HTTP POST * **Request Type:** `Content-Type: application/json` **Request Body Example:** ```jsx { "fromChainType":"BTC", "toAddress":"0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "toChainType":"ETH", "amount":"0.03", "tokenPairID":"416" } ``` Please fill in the correct values as required: * **fromChainType:** Fixed as `BTC`. * **toAddress:** Recipient's address. **Ensure the address is correct to avoid asset loss**. * **toChainType:** Destination chain type. * **amount:** Amount to transfer (in BTC). * **tokenPairID:** Cross-chain pair ID. **2) Response Request** * **Success** * Successful return with HTTP status code: `200` * Successful return with data: ```jsx { "success":true, "data":{ "ota":"bc1p0s57ehsgnva826zff0p4l6dajsp7cdac9uw78j2vwcqhew3cvgvqvhm6z3" } } ``` * **Failure** * Failed return with HTTP status code: `400` (Input parameter error) or `500` (Internal server error). * Failed return with data: `{success: false, error: "XXXXXXX"}` **Step 2: Submit cross-chain ID (txHash)** After completing the BTC transfer to the one-time address using the front-end wallet (e.g., OKX extension wallet), this API is used to submit the transaction ID (`txid`) for tracking and monitoring. **1) Send Request** * **Request Endpoint:** [`https://bridge-api.wanchain.org/api/submitBtcOrder`](https://bridge-api.wanchain.org/api/submitBtcOrder) * **Request Method:** HTTP POST * **Request Type:** `Content-Type: application/json` **Request Body Example:** ```jsx { "fromChainType":"BTC", "toAddress":"0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "toChainType":"ETH", "amount":"0.03", "tokenPairID":"416", "ota":"bc1p0s57ehsgnva826zff0p4l6dajsp7cdac9uw78j2vwcqhew3cvgvqvhm6z3", "txid":"0e9086c7568b6892bbbd1e407791749b2ed04efd7d1302f54236875a94b23dad", } ``` Please fill in the correct values as required. The information is the same as the previous step, with the addition of the `ota` and `txid` fields: * **fromChainType:** Fixed as `BTC`. * **toAddress:** Recipient's address. **Ensure the address is correct to avoid asset loss**. * **toChainType:** Destination chain type. * **amount:** Amount to transfer (in BTC). * **tokenPairID:** Cross-chain pair ID. * **ota:** One-time address generated in Step 1. * **txid:** Transaction ID of the user's transfer to the one-time address. **2) Response Request** * **Success** * **Successful return with HTTP status code:** `200` * **Successful return with data:** ```jsx { "success":true } ``` * **Failure** * **Failed return with HTTP status code:** `400` (Input parameter error) or `500` (Internal server error). * **Failed return with data:** `{success: false, error: "XXXXXXX"}` **Step 3: Query cross-chain status** The status query API uses the transaction ID (`txid`) as the key for querying the cross-chain status. The query interface and return value rules for cross-chain status are the same as those for other cross-chain status queries, with TXID as the key value for querying. **Example:** ```json ``` **Response:** ```json { "success": true, "data": { "timestamp": 1715244313, "tokenPair": "14", "lockHash": "c3bf5e2d50bbb5574659014478b691c1173fc783f82143105519e876d42f1443", "redeemHash": null, "status": "Processing", "sendAmount": "620000", "receiveAmount": "450000" } } ``` #### 2.2.3 Solana Cross-chain API The API requires **Base64** format for both the token address and user address. **API Endpoint:** \[`https://bridge-api.wanchain.org/api/createTx2]()` **Example:** ``` { "fromChain": "SOL", "toChain": "WAN", "fromAccount": "2SFMj2XNzFCTzeQE8rEk82MxBq3A4u4J6uQvEnpmcqyh", "fromToken": "Es9vMFrzaCERmJfrF4H2FYD4KCoNkY11McCe8BenwNYB", "toToken": "0x11e77e27af5539872efed10abaa0b408cfd9fbbd", "toAccount": "0x4Cf0A877E906DEaD748A41aE7DA8c220E4247D9e", "amount": "100", "partner": "tester" } ``` **Response:** ```jsx { "success": true, "data": { "tx": "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", "receiveAmount": "99.8", "chainId": "0x384", "feeAndQuota": { "symbol": "USDT", "minQuota": "400000", "maxQuota": "7174693343715", "networkFee": { "value": "100000", "isPercent": false }, "operationFee": { "value": "0.002", "isPercent": true, "minFeeLimit": "200000", "maxFeeLimit": "100000000" } } } } ``` **Usage:** ```jsx const rawTx = ret.data.tx; // defautl base64 const data = xxxx; // base58 (Optional) (OKX api return in this format) export async function sendSolanaTx({rawTx, data}) { console.log('Send Solana tx', {rawTx}); const provider = window.solana; const connection = new Connection('https://YOUR_SOLANA_RPC'); // Deserialize the transaction using VersionedTransaction const buffer = rawTx ? Buffer.from(rawTx, 'base64') : Buffer.from(bs58.decode(data)); const tx = VersionedTransaction.deserialize(new Uint8Array(buffer)); const { blockhash } = await connection.getLatestBlockhash(); tx.message.recentBlockhash = blockhash; console.log('Deserialized Solana transaction:', tx); // Sign and send transaction const signature = await provider.signAndSendTransaction(tx, {skipPreflight: false, maxRetries: 20}); console.log('Transaction sent successfully', 'success'); const signatureStr = typeof signature === 'object' ? signature.signature?.toString() : signature.toString(); console.log('Transaction signature:', 'info', signatureStr); // sleep 3 seconds await sleep(3000); return signatureStr; } ``` #### 2.2.4 Cardano Cross-chain API This section details the API for transferring tokens from a user's Cardano account to another blockchain. The Cardano account can be either a payment address or a base address (also referred to as an enterprise address, which combines payment and stake addresses). * **API Endpoint**: [`https://bridge-api.wanchain.org/api/createTx2`](https://bridge-api.wanchain.org/api/createTx2) * **Testnet Endpoint:** `https://bridge-api.wanchain.org/api/testnet/createTx2` * **HTTP Request Method**: POST * **HTTP Request Content Type**: `Content-Type: application/json` **Request Body** **Example:** ```json {  "fromChain": "ADA",  "toChain": "ETH",  "fromAccount": "addr_test1vq......",  "toAccount": "0x1bBdd8f.....",  "amount": "1.118",  "fromToken": "0x0000000000000000000000000000000000000000",  "toToken": "0xfdee9454b39419a17b151e2922778df3712d0026",  "partner": "newDex" } ``` **Parameters**: * **fromChain**: The source chain, fixed as `ADA`. * **toChain**: The destination chain name. Refer to **Section 2.2.1** or retrieve it from token-pair information. * **fromAccount**: The user's Cardano wallet address, which can be either a payment address or a base address. * **toAccount**: The recipient's address on the destination chain. **Ensure the address is correct to avoid asset loss.** * **amount**: The transfer amount, which supports decimal values (e.g., `"1.12345"`). * **fromToken**: The coin or token address on the ADA chain. Use `0x0000000000000000000000000000000000000000` for ADA coins or the encoded `unit` value for tokens. Retrieve this from token-pair information. * **toToken**: The token address on the destination chain. Ensure it matches the token-pair information. * **partner**: Optional field for partner identification. **Response Example:** ```json { "success": true, "data": {   "tx": "84a50081825...7479706501",   "receiveAmount": "1.118",   "chainId": "0x385",   "feeAndQuota": {     "symbol": "ADA",     "minQuota": "400000",     "maxQuota": "7174693343715",     "networkFee": {       "value": "100000",       "isPercent": false     },     "operationFee": {       "value": "0.002",       "isPercent": true,       "minFeeLimit": "200000",       "maxFeeLimit": "100000000"     }   } } } ``` {% hint style="info" %} The `data.tx` field is the full transaction hex string. {% endhint %} **Usage:** ```jsx import * as CardanoWasm from "@emurgo/cardano-serialization-lib-asmjs-gc"; // Example for reference to process the txHex return from endpoint async function signAndSendTransaction(txHex) { if (window.cardano && window.cardano.lace) { const handler = async function (walletApi) { try { const tx = CardanoWasm.Transaction.from_hex(txHex); // 1) sign transaction const witnessSetHex = await walletApi.signTx(txHex); const witnessSet = CardanoWasm.TransactionWitnessSet.from_hex(witnessSetHex); const redeemers = tx.witness_set().redeemers(); if (redeemers) { witnessSet.set_redeemers(redeemers); } const signedTx = CardanoWasm.Transaction.new(tx.body(), witnessSet, tx.auxiliary_data()); // 2) send let txHash = await walletApi.submitTx(signedTx.to_hex()); console.debug("sendTransaction() got txHash: %O", txHash); return txHash; } catch (error) { console.error("Failed to sign transaction:", error); throw error; // Re-throw error for handling in the caller } } const walletApi = await window.cardano.lace.enable().catch((err) => { console.error("Cardano wallet is not enabled"); throw new Error("Cardano wallet not enabled"); }); return handler(walletApi); } else { console.error("Cardano wallet is not found"); throw new Error("Cardano wallet not found"); } } ``` {% hint style="info" %} You need to install `"@emurgo/cardano-serialization-lib-asmjs-gc": "^12.0.1"` to process the transaction hex string returned by this API. Other versions may fail when submitting transactions, so please verify compatibility on your own. {% endhint %} #### 2.2.6 Vechain Cross-chain Testnet API path: `https://bridge-api.wanchain.org/api/testnet/createTx2` HTTP POST request body: ```jsx { "fromChain": "VET", "toChain": "WAN", "fromAccount": "0xF6eB3CB4b187d3201AfBF96A38e62367325b29F9", "fromToken": "0x0000000000000000000000000000456e65726779", "toToken": "0x91cb1718bb65aef73e16deb6b068aea5dd4fcad1", "toAccount": "0xF6eB3CB4b187d3201AfBF96A38e62367325b29F9", "amount": "1" } ``` API Response: ```jsx { "success": true, "data": { "approveCheck": { "from": "0xF6eB3CB4b187d3201AfBF96A38e62367325b29F9", "token": "0x0000000000000000000000000000456e65726779", "to": "0x8dc369fa992f2f3c38474e84b0a93cc9957b1b73", "amount": "1000000000000000000" }, "tx": { "from": "0xF6eB3CB4b187d3201AfBF96A38e62367325b29F9", "to": "0x8dc369fa992f2f3c38474e84b0a93cc9957b1b73", "value": "0x0", "data": "0x257011b6000000000000000000000000000000000000000000000000006465765f32323800000000000000000000000000000000000000000000000000000000000003a60000000000000000000000000000000000000000000000000de0b6b3a764000000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000014f6eb3cb4b187d3201afbf96a38e62367325b29f9000000000000000000000000" }, "receiveAmount": "1.0", "chainId": "0x186aa", "txDataDetail": { "func": "userLock(bytes32,uint256,uint256,bytes)", "params": [ "0x000000000000000000000000000000000000000000000000006465765f323238", "934", "1000000000000000000", "0xF6eB3CB4b187d3201AfBF96A38e62367325b29F9" ] }, "feeAndQuota": { "symbol": "VTHO", "minQuota": "0", "maxQuota": "1160075277287119653415045092614", "networkFee": { "value": "0", "isPercent": false }, "operationFee": { "value": "0", "isPercent": false, "discountPercent": "1" } } } } ``` Front end code example: ```jsx import { DAppKit } from '@vechain/dapp-kit'; import { ABIContract, Address, Clause } from '@vechain/sdk-core'; async function getVechainProvider(isTestnet: boolean) { console.log('Getting Vechain provider...', isTestnet); const DefaultProvider = { mainnet: "", testnet: "" } const kit: DAppKit = new DAppKit({ // { thor, vendor, wallet } nodeUrl: DefaultProvider[isTestnet ? 'testnet' : 'mainnet'], genesis: (isTestnet) ? 'test' : 'main' }); kit.wallet.setSource('veworld'); let {account} = await kit.wallet.connect(); if (!account) { throw new Error('Failed to connect to wallet'); } console.log('account', account); return kit; } async function sendVeTransaction(kit: DAppKit, clauses: Connex.VM.Clause[], sender: string) { console.log('Sending transaction...', clauses, sender); let tx = await kit.vendor.sign('tx', clauses).signer(sender); let { txid } = await tx.request(); return txid; } function generatorErc20ApproveData(erc20Addr: string, spenderAddr: string, value: string) { let clauses = [Clause.callFunction( Address.of(erc20Addr), ABIContract.ofAbi(ERC20_ABI as any).getFunction('approve'), [spenderAddr, value] )]; return clauses; } if (formData.fromChain === 'VET') { const kit = await getVechainProvider(isTestnet); if (result.data.approveCheck) { const rpcUrl = isTestnet ? '' : ''; let provider = new ethers.JsonRpcProvider(rpcUrl); const clauses = generatorErc20ApproveData(result.data.approveCheck.token, result.data.approveCheck.to, result.data.approveCheck.amount); let txHash = await sendVeTransaction(kit, clauses, formData.fromAccount); await provider.waitForTransaction(txHash); } let tx = await sendVeTransaction(kit, [ { to: result.data.tx.to, data: result.data.tx.data, value: result.data.tx.value || '0x0', } ], formData.fromAccount); } ``` **API Demo UI code:** **API Demo UI:**