fhEVM
WebsiteLibrariesProduct & ServicesDevelopersSupport
0.3
0.3
  • <- Home
  • What is Zama's fhEVM
    • Overview
    • Whitepaper
  • Getting Started
    • Connecting to Zama Devnet
    • Using Zama Faucet
    • Local dev node
  • How to
    • Write contract
      • Using Hardhat
      • Using Remix
      • Other development environment
    • Use encrypted types
    • Operations on encrypted types
    • Generate random number
    • Write conditions
    • Decrypt and reencrypt
    • Estimate gas
    • Common pitfalls and best practises
  • API
    • Function specifications
  • Client SDK
    • Getting started
      • Using Node
      • Using a template
      • Other frontend tooling
      • Using CLI
    • Setup an instance
    • Encrypt an input
    • Get a reencryption
    • Examples
      • Transfer tokens (node)
      • Get balance (node)
  • Resources
    • Examples
    • Tutorials
    • Repositories
  • Future Developments
    • Development Roadmap
  • 🔗Support
    • Community forum
    • Telegram
    • FHE.org discord
    • Twitter
Powered by GitBook

Libraries

  • TFHE-rs
  • Concrete
  • Concrete ML
  • fhEVM

Developers

  • Blog
  • Documentation
  • Github
  • FHE resources

Company

  • About
  • Introduction to FHE
  • Media
  • Careers
On this page

Was this helpful?

Export as PDF
  1. Client SDK
  2. Examples

Transfer tokens (node)

const { createInstance } = require("fhevmjs");
const { Wallet, JsonRpcProvider, Contract } = require("ethers");

const contractInfo = require("./EncryptedERC20.json");

const CONTRACT_ADDRESS = "0x309cf2aae85ad8a1db70ca88cfd4225bf17a7482";

const provider = new JsonRpcProvider(`https://devnet.zama.ai/`);

const signer = new Wallet("0x92293977156de6e03b20b26708cb4496b523116190b5c32d77cee8286d0c41f6", provider);

let _instance;

const getInstance = async () => {
  if (_instance) return _instance;

  // 1. Get chain id
  const network = await provider.getNetwork();
  const chainId = +network.chainId.toString(); // Need to be a number

  // Get blockchain public key
  const ret = await provider.call({
    // fhe lib address, may need to be changed depending on network
    to: "0x000000000000000000000000000000000000005d",
    // first four bytes of keccak256('fhePubKey(bytes1)') + 1 byte for library
    data: "0xd9d47bb001",
  });
  const decoded = ethers.AbiCoder.defaultAbiCoder().decode(["bytes"], ret);
  const publicKey = decoded[0];

  // Create instance
  _instance = createInstance({ chainId, publicKey });
  return _instance;
};

const transfer = async (to, amount) => {
  // Initialize contract with ethers
  const contract = new Contract(CONTRACT_ADDRESS, contractInfo.abi, signer);
  // Get instance to encrypt amount parameter
  const instance = await getInstance();
  const encryptedAmount = instance.encrypt32(amount);

  const transaction = await contract["transfer(address,bytes)"](to, encryptedAmount);
  return transaction;
};

transfer("0xa83a498Eee26f9594E3A784f204e507a5Fae3210", 10);
PreviousExamplesNextGet balance (node)

Last updated 1 year ago

Was this helpful?