Linked Questions

5
votes
1answer
666 views

Accessing the last function parameter from msg.data

I have a fallback (unnamed) function in my contract and I know that the last parameter (or first, does not matter) passed is always an uint. Is it possible to somehow access it though the msg.data?
2
votes
1answer
595 views

Creating raw transactions for sending ERC721 tokens

I was able to create raw transactions for eth following this article https://medium.com/blockchain-musings/how-to-create-raw-transactions-in-ethereum-part-1-1df91abdba7c However, how can I create raw ...
1
vote
1answer
742 views

How to interact with Smart Contract in private network with 3 nodes using Mist?

I'm looking for a method to interact with a smart contract deployed from the official Ethereum wallet. My client is Geth,and I've synchronized 3 nodes. How is possible to recall a simple method of ...
1
vote
2answers
353 views

Can you interact with a contract by only looking at its bytecode?

Suppose you don't have the source of a contract, but have its bytecode. Can you theoretically interact with it somehow, or see what it does, by only looking at its bytecode? Can functionality be ...
6
votes
1answer
113 views

Why is the returndata of a function returning bytes formatted in a weird way?

Solidity 0.4.25. Consider this code contract A{ function test() public view returns (bytes){ bytes memory output = abi.encodePacked(bytes32(1)); return output; } } The ...
1
vote
1answer
393 views

how to retrieve function call address from deployed contract for usage with MetaMask send + transaction data?

I've deployed a contract into my testrpc network. $ truffle deploy Using network 'development'. Running migration: 1_initial_migration.js Deploying Migrations... Migrations: ...
3
votes
1answer
255 views

Deploy contract hangs in Mist

I'm not able to deploy any contract (the greeter contract does not work either) using Mist 0.8.6 in Windows. The deployment just hangs there and nothing really happens. Is there a way to figure out ...
2
votes
1answer
181 views

How does a contract's constructor work and load input values?

I set up the following contract: pragma solidity ^0.4.25; contract Simplest { uint x; constructor(bool _lucky) public { if (_lucky == true) { x = 7; } else { ...
0
votes
1answer
270 views

Modifiers misunderstanding

pragma solidity ^0.4.0; contract test { bool test_bool1 = false; bool test_bool2 = true; modifier test_modifier(bool _test_bool){ if (_test_bool == false) throw; _; } ...
3
votes
1answer
148 views

How to determine the contract method called and with what parameters from a transaction hash?

Suppose I have a transaction hash and it belongs to some transaction which was done on a smart contract. From the hash, how do I determine what was the contract method which was called and with what ...
1
vote
2answers
66 views

Why do I need to have exact same code to load contract from address in Remix IDE?

I tried to interact with the deployed contract and i don't have its code. so i found out the contract address and tried to load contract from address in Remix IDE! isn't this possible? WHY?
0
votes
2answers
50 views

How can I send alerts to others on ethereum blockchain?

I want to know if it is possible to build an app that can send alerts to others on ethereum blockchain. If it's possible then how fast do you think the alerts can be sent and then received by the ...

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