All Questions
12 questions
195
votes
2
answers
60k
views
What is the difference between a transaction and a call?
What is the difference between a transaction and a call? In some interfaces, I can interact with contracts via calls or via transactions. What is the difference between the two, and can contracts also ...
- 7,636
6
votes
1
answer
15k
views
Execute transaction Approve directly against contract address (without ABI)
Solved
For now, you will always need the ABI to execute a call against the ethereum network with web3. A simple way is to reconstruct the function you wish to execute is to, either create a separate ...
1
vote
2
answers
823
views
How to track incoming to smart contract transactions using web3js?
I've got one Ethereum smart contract which calls functions of the other one. How could I track these calls using web3js or some other tool if it is possible at all? I need it because I want to execute ...
1
vote
1
answer
682
views
How to simulate multiple consecutive transactions and get the resulting state?
I'm trying to simulate a transaction on the public blockchain that invokes a contract's method with certain parameters. Then I want to make a follow-up transaction with some other method call.
I ...
- 181
2
votes
1
answer
6k
views
How to Deploy and call a contract? Address needed beforehand?
I want to store a string from a script in node.js to blockchain.
This is the contract.
pragma solidity ^0.4.0;
contract SimpleStorage {
string storedData;
function set(string x) {
...
- 135
4
votes
1
answer
6k
views
Can I send ethereum to a contract outside of its constructor?
How do I fund Solidity contracts with Ether? The example in the Solidity FAQ, http://solidity.readthedocs.io/en/develop/frequently-asked-questions.html#store-ether-in-a-contract, funds a contract via ...
- 614
7
votes
1
answer
3k
views
Passing ether with call to Solidity function
I have deployed a contract to testnet which appears to function.
I have a function named contribute which gets the ether from the msg.value. The function is below and doesn't take any arguments.
I ...
- 397
3
votes
1
answer
2k
views
NodeJS+web3 - Reading from a contract works, how about writing to a contract? [duplicate]
In Mist you can call functions of contracts in two ways:
On the left panel, to call functions that read from a contract (the result is immediate).
On the right panel, to call functions that write ...
- 152
4
votes
1
answer
936
views
When a contract calls another contracts, can it return values?
When a contract calls another contract, are values returned ? I've seen things like:
function foo() external returns (bool success) {
if( ... ) throw;
return true;
}
But have read that calls ...
- 157
1
vote
0
answers
259
views
How to access data from web3.eth.Contracts.send() function?
If I run this chunk of code from my async function I will get a transaction receipt as an output:
const response = await contract.methods.recoverAddr(hex_msg,
v_decimal,r, s).send({from: accounts[0]}...
0
votes
1
answer
224
views
Sending parameters via the transaction Object
This works just fine:
myContractObject.doSomething(i, function(err, result) {
if (err) {
console.log(err)
} else {
doSomethingElse(result)
}
})
However, this doesn't:
...
- 614
0
votes
1
answer
171
views
How to form the transactionObject in a metamask enforced async call?
Normally, for a contract call (i.e. something that does not update ethereum), I would simply do: var something = myContractObject.getSomething().
I've just started using metamask, and unfortunately, ...
- 614