Blockchain By Example

Option one – using the ABI

As we did in the Ctontine contract, the regular way to interact with other contracts is to call (invoke) a function on a contract object (we borrow here the OOP terminology). For example, we can call a remote function from a remote contract, ContractA , as follows: ContractA.Remotefunction(arguments).

But to be able to make the invocation this way, we need to define (in the same Solidity file) an abstract form of ContractA. For instance, if we have a contract, ContractA, then the code is as follows:

contract ContractA {    function f(uint256 a, string s) payable returns (bool) {        //your code here        return true;    }}

If this contract is deployed in the blockchain, let’s say under the 0x123456 address, and we want to call ...