svanas

const client: IWeb3 = TWeb3.Create('https://<your-node-name>.quiknode.pro/<your-token>/');
web3.eth.blockNumber(client, procedure(num: BigInteger; err: IError)
begin
  TThread.Synchronize(nil, procedure
  begin
    if Assigned(err) then
      MessageDlg(err.Message, TMsgDlgType.mtError, [TMsgDlgBtn.mbOK], 0)
    else
      MessageDlg(num.ToString, TMsgDlgType.mtInformation, [TMsgDlgBtn.mbOK], 0);
  end);

svanas

web3.eth.call(TWeb3.Create(
  Sepolia.SetRPC(                                   // Sepolia test net
  'https://sepolia.infura.io/v3/your-project-id')), // RPC access to Sepolia
  '0x643C9Db08aBE4D95e4F2Afc733F78b601b84007A',     // smart contract address
  'myFirstHelloWorld()', [], procedure(tup: TTuple; err: IError)
begin
  TThread.Synchronize(nil, procedure
  begin
    if Assigned(err) then
      MessageDlg(err.Message, TMsgDlgType.mtError, [TMsgDlgBtn.mbOK], 0)

svanas

const ERC20: IERC20 = TERC20.Create(TWeb3.Create(
  Sepolia.SetRPC('https://sepolia.infura.io/v3/your-project-id')), // Sepolia testnet
  '0xe28a3A4BFbf285676405cF55354f8b504D844f3c');                   // TST smart contract address
ERC20.Transfer(
  TPrivateKey('24622d680bb9d6d80c4d3fb4b4818e738de64b521948b1b1c85616eeeda54ee1'), // from private key
  '0xaDDcedc01C1070bCE0aF7eb853845e7811EB649C',                                    // to public key
  1000000000000000,                                                                // 0.001 TST
  procedure(hash: TTxHash; err: IError)
  begin
    TThread.Synchronize(nil, procedure

svanas

uses
  web3.eth.crypto, web3.eth.types;

procedure TForm1.Button1Click(Sender: TObject);
begin
  ShowMessage(
    web3.eth.crypto.sign(
      TPrivateKey('b5b1870957d373ef0eeffecc6e4812c0fd08f554b37b233526acc331bf1544f7'),
      'Hello, World!'
    ).ToHex

svanas

const Client: IWeb3 = TWeb3.Create('https://mainnet.infura.io/v3/your-project-id');
web3.eth.call(Client, '0xB8c77482e45F1F44dE1745F52C74426C631bDD52', 'symbol()', [], procedure(tup: TTuple; err: IError)
begin
  if Assigned(err) then
  begin
    TThread.Synchronize(nil, procedure
    begin
      MessageDlg(err.Message, TMsgDlgType.mtError, [TMsgDlgBtn.mbOK], 0)
    end);
    EXIT;

svanas

uses
  // Delphi
  System.Classes,
  System.JSON,
  System.UITypes,
  // FireMonkey
  FMX.Controls,
  FMX.Controls.Presentation,
  FMX.Dialogs,
  FMX.Forms,

svanas

web3.eth.write(Client,
  TPrivateKey('b5b1870957d373ef0eeffecc6e4812c0fd08f554b37b233526acc331bf1544f7'), // from private key
  '0x1a306890df22c0965b0b1515a8082f8301d3d18e',                                    // to smart contract
  'setNumber(uint256)', [143],
  procedure(rcpt: ITxReceipt; err: IError) begin end);

svanas

web3.eth.write(Client,
  TPrivateKey('b5b1870957d373ef0eeffecc6e4812c0fd08f554b37b233526acc331bf1544f7'), // from private key
  '0x1a306890df22c0965b0b1515a8082f8301d3d18e',                                    // to smart contract
  'incrementNumber()', [],
  procedure(rcpt: ITxReceipt; err: IError) begin end);

svanas

web3.eth.call(Client,
  '0x1a306890df22c0965b0b1515a8082f8301d3d18e',
  'getNumber()', [], procedure(qty: BigInteger; err: IError)
begin
  TThread.Synchronize(nil, procedure
  begin
    if Assigned(err) then
      MessageDlg(err.Message, TMsgDlgType.mtError, [TMsgDlgBtn.mbOK], 0)
    else
      ShowMessage(qty.ToString);

svanas

var
  Client: IWeb3;

procedure TForm1.FormCreate(Sender: TObject);
begin
  Client := TWeb3.Create(Sepolia.SetRPC('https://sepolia.infura.io/v3/your-project-id'));
end;