is a wasy way to wait complete?

[yonghumeijj]

if i want do three step like 1.approve
2.sendTrans 3.transfer

because library is run in task so how can i wait affrove ok then sendtrans then transfer?

Delphi do not have something like await/async

[svanas]

Everything Delphereum does is async. If you want to approve a token and then wait for the transaction to get mined before you transfer (or do anything else), here is how:

const erc20 = TERC20.Create(client, token);
erc20.ApproveEx(owner, spender, web3.Infinite, procedure(rcpt: ITxReceipt; err: IError)
begin
  if Assigned(err) then
  begin
    // handle error
    EXIT;
  end;
  erc20.TransferEx(owner, blah blah blah, procedure(rcpt: ITxReceipt; err: IError)
  begin
    if Assigned(err) then
    begin
      // handle error
      EXIT;
    end;
    // continue with your next step
  end);
end);

As a general rule, the non-Ex functions -- such as Approve() and Transfer() -- return immediately with a hash of the transaction, while the Ex functions -- such as ApproveEx() and TransferEx()-- wait for the transaction to get mined and then return a receipt of the transaction.

[yonghumeijj]

Everything Delphereum does is async. If you want to approve a token and then wait for the transaction to get mined before you transfer (or do anything else), here is how:

const erc20 = TERC20.Create(client, token);
erc20.ApproveEx(owner, spender, web3.Infinite, procedure(rcpt: ITxReceipt; err: IError)
begin
  if Assigned(err) then
  begin
    // handle error
    EXIT;
  end;
  erc20.TransferEx(owner, blah blah blah, procedure(rcpt: ITxReceipt; err: IError)
  begin
    if Assigned(err) then
    begin
      // handle error
      EXIT;
    end;
    // continue with your next step
  end);
end);

As a general rule, the non-Ex functions -- such as Approve() and Transfer() -- return immediately with a hash of the transaction, while the Ex functions -- such as ApproveEx() and TransferEx()-- wait for the transaction to get mined and then return a receipt of the transaction.

SendTrans cant do like this. have other way?thanks

[yonghumeijj]

Everything Delphereum does is async. If you want to approve a token and then wait for the transaction to get mined before you transfer (or do anything else), here is how:

const erc20 = TERC20.Create(client, token);
erc20.ApproveEx(owner, spender, web3.Infinite, procedure(rcpt: ITxReceipt; err: IError)
begin
  if Assigned(err) then
  begin
    // handle error
    EXIT;
  end;
  erc20.TransferEx(owner, blah blah blah, procedure(rcpt: ITxReceipt; err: IError)
  begin
    if Assigned(err) then
    begin
      // handle error
      EXIT;
    end;
    // continue with your next step
  end);
end);

As a general rule, the non-Ex functions -- such as Approve() and Transfer() -- return immediately with a hash of the transaction, while the Ex functions -- such as ApproveEx() and TransferEx()-- wait for the transaction to get mined and then return a receipt of the transaction.

if i want do many step. this way will be very deep.

xxxxx(x, procedure begin yyyyy(y, procedure begin zzzz(z, procedure begin end ) end ); end; )

like this more and more deep....