- name
- hedera-tx-builder
- description
- Build and sign Hedera transactions. Use for: (1) Creating HBAR transfers, (2) Token operations, (3) Smart contract calls, (4) Submitting to Hedera network.
Hedera Transaction Builder
Setup
npm install @hashgraph/sdk
Client Setup
import { Client, AccountBalanceQuery, Hbar } from '@hashgraph/sdk';
const client = Client.forMainnet();
// Or for testnet:
const client = Client.forTestnet();
Transfer HBAR
import { TransferTransaction, Hbar } from '@hashgraph/sdk';
const tx = new TransferTransaction()
.addHbarTransfer(fromAccountId, new Hbar(-100)) // send
.addHbarTransfer(toAccountId, new Hbar(100)) // receive
.setTransactionMemo("Payment for goods");
// Sign with hashpack or operator
const signTx = await tx.sign(operatorKey);
const result = await signTx.execute(client);
Key Transaction Types
AccountCreate
new AccountCreateTransaction()
.setKey(publicKey)
.setInitialBalance(new Hbar(10))
.setAccountMemo("My account");
TokenAssociate
new TokenAssociateTransaction()
.setAccountId(accountId)
.setTokenIds([tokenId1, tokenId2]);
TopicMessage
new TopicMessageTransaction()
.setTopicId(topicId)
.setMessage("Hello Hedera!");
Network Endpoints
- Mainnet:
https://mainnet.hashio.io/api - Testnet:
https://testnet.hashio.io/api
Important Concepts
- Hbar: 1 HBAR = 100,000,000 tinybars
- Account ID: Format
shard.realm.num (e.g., 0.0.12345) - Transaction Fee: Small HBAR fee for each transaction
- Transaction Valid Duration: 180 seconds by default
