Hottest Questions This Month

3

votes

3

answers

259

views

Can I mine only low-value blocks?

mining gas-price

answered Dec 27 '19 at 22:05 David Schwartz 171

3

votes

1

answer

380

views

What's the vulnerability in my contract?

modified Dec 28 '19 at 3:18 shane 4,796

2

votes

4

answers

328

views

How essential is a knowledge of Javascript to learning solidity/ethereum?

javascript nodejs

modified Jan 12 at 12:27 Rob Hitchens - B9lab 37.4k

1

vote

2

answers

131

views

How is authorization handled in smart contracts

go-ethereum web3js private-blockchain quorum privacy

modified yesterday faizal 163

2

votes

4

answers

43

views

ABI and Bytecode stored inside Contract

contract-development abi bytecode

answered 2 days ago Steven V 416

1

vote

2

answers

113

views

Solidity 0.6.0 address(this).balance throws error invalid opcode

solidity opcode solidity-0.6.0

modified Dec 29 '19 at 11:34 Chris 518

1

vote

1

answer

191

views

MetaMask verification screen doesn't show amount or token when I use 'approveAndCall' to transfer tokens to a contract

metamask contract-invocation

answered Dec 26 '19 at 0:10 Yogesh - EtherAuthority.io 360

2

votes

1

answer

80

views

What algorithm is used to generate nonce hash in genesis file?

nonce genesis

modified Dec 27 '19 at 12:40 Daniel Portugal 408

5

votes

1

answer

78

views

Solidity 0.6.0 and address(f) to f.address

solidity contract-upgrading

modified Dec 29 '19 at 10:11 alberto 1,563

1

vote

2

answers

92

views

Can a contract be deployed through a node which is not owned by the contract owner?

contract-development

answered Dec 26 '19 at 18:10 Nicolas Massart 5,457

2

votes

3

answers

39

views

How are transactions with the same gas price ordered in a block?

go-ethereum mining parity txpool

modified Jan 7 at 19:49 Nicolas Massart 5,457

1

vote

1

answer

58

views

Which contract's address?

solidity addresses

modified Jan 11 at 10:37 K S 81

1

vote

1

answer

94

views

How Can You Find the Ethereum Provider on Web3 Browsers Other Than MetaMask?

web3js metamask javascript web3js-v1.x

answered Jan 6 at 18:43 Rob Hitchens - B9lab 37.4k

3

votes

1

answer

57

views

Is it possible to perform a try-catch in Solidity?

solidity revert-opcode keyword solidity-0.6.0 try-catch

modified Dec 27 '19 at 22:51 shane 4,796

1

vote

1

answer

69

views

Exceptions when compiling a contract using Solidity version 0.6.0 on Remix

solidity remix

answered Dec 27 '19 at 21:34 Rick Park 2,227

4

votes

1

answer

82

views

It possible to hard fork a private network without resyncing chain from scratch?

go-ethereum private-blockchain hardforks

answered Jan 4 at 4:51 fixanoid 1,342

0

votes

3

answers

30

views

How can I get proper gas price for fast transaction?

gas-price

answered Dec 29 '19 at 13:12 Niklas Feurstein 2,971

0

votes

2

answers

75

views

why did this transaction fail?

solidity web3js erc-20 ethereumjs

modified Jan 14 at 17:29 Chan-Ho Suh 138

3

votes

3

answers

35

views

Revising Smart Contracts [closed]

contract-debugging

answered Jan 7 at 19:43 Sudeep 41

2

votes

2

answers

41

views

If a transaction ends up in an orphaned/forked block, what happens to subsequent transactions?

transactions nonce receipts

answered Dec 27 '19 at 2:59 Ismael 18.8k

0

votes

4

answers

41

views

Mutating slot 0 of a storage array in Solidity assembly

solidity storage arrays

answered Dec 31 '19 at 18:57 Mikhail Vladimirov 4,059

3

votes

1

answer

67

views

Contract does not exist at address

remix contract-deployment nodejs quorum

modified Jan 20 at 17:48 faizal 163

2

votes

2

answers

38

views

Full Node Bigger Than Online Reports?

go-ethereum etherscan geth-debugging

modified Jan 20 at 6:13 Raghav Sood 3,340

1

vote

2

answers

48

views

Reinstalled MetaMask, account lost?

ether wallets metamask addresses accounts

modified Dec 29 '19 at 0:41 Rick Park 2,227

0

votes

2

answers

48

views

How to fight against a cheating node?

transactions security nodes

answered Jan 5 at 19:24 Rob Hitchens - B9lab 37.4k

1

vote

2

answers

37

views

Is it possible to circumvent a require statement if the ordering of the requirements are incorrect?

solidity tokens security reentrant-attacks

answered Jan 10 at 14:06 K S 81

0

votes

1

answer

34

views

Why won't a Byte code generate for the below code? The Byte code is not generating in the contract details

bytecode

modified Dec 28 '19 at 14:38 Niklas Feurstein 2,971

0

votes

1

answer

56

views

Total Unique Addresses Count of Ethereum Classic

addresses ethereum-classic

modified 41 mins ago Mikhail Vladimirov 4,059

0

votes

2

answers

26

views

Could someone explain basic transferFrom functionality

erc-20

answered Jan 20 at 20:35 Mikhail Vladimirov 4,059

0

votes

2

answers

20

views

How to generate a unique random number in web3.js?

web3js randomness

modified Jan 10 at 19:55 Steven V 416

2

votes

1

answer

42

views

Does ganache-cli support istanbul hardfork?

ganache istanbul

answered Dec 30 '19 at 19:53 iamdefinitelyahuman 1,167

3

votes

1

answer

41

views

Why are blocks imported so slowly? - Geth node

go-ethereum aws

answered Jan 15 at 9:02 Richard Horrocks 27k

0

votes

2

answers

31

views

Invalid opcode exception when trying to resize a storage array

solidity dapps arrays exceptions

modified 2 days ago UTF-8 231

1

vote

1

answer

39

views

Is it safe to do multiple payments in between locks (Reentrancy Guard)?

solidity gas security reentrant-attacks istanbul

answered Jan 3 at 1:13 Rob Hitchens - B9lab 37.4k

1

vote

1

answer

30

views

Storing multiple values in one key mapping (Solidity)

solidity remix storage mapping

modified Jan 9 at 18:25 Rob Hitchens - B9lab 37.4k

0

votes

1

answer

38

views

the tx doesn't have the correct nonce. account has nonce of: 12 tx has nonce of: 3 - Ganache

web3js contract-invocation nodejs ganache nonce

modified Dec 27 '19 at 8:57 Rob Hitchens - B9lab 37.4k

2

votes

1

answer

48

views

What are the virtual and override keywords in Solidity?

solidity override keyword solidity-0.6.0 virtual

modified Dec 28 '19 at 0:06 shane 4,796

0

votes

2

answers

37

views

Use uint[] to map uint(address) to uint

solidity gas dapps evm

modified Jan 8 at 20:29 Rob Hitchens - B9lab 37.4k

1

vote

1

answer

45

views

Public variable getter shows as transaction in Remix

solidity remix solidity-0.5.0 local-variables solidity-0.6.0

modified Jan 14 at 22:48 alberto 1,563

0

votes

1

answer

44

views

machine learning (clustering algorithm) in smart contract [closed]

contract-development machine-learning

modified Jan 4 at 12:08 Rick Park 2,227

0

votes

2

answers

33

views

IP address and system details of msg.sender

solidity go-ethereum contract-development contract-design

answered Jan 3 at 16:08 tomsoft 168

0

votes

1

answer

54

views

How to integrate ERC20 token to microjob website?

go-ethereum ethereum-wallet-dapp

modified Jan 12 at 4:26 Ismael 18.8k

0

votes

2

answers

32

views

How can I send tokens to large number of addresses?

cpp-ethereum gas-price

modified Jan 13 at 10:14 goodvibration 10.1k

2

votes

1

answer

31

views

How can I slice bytes, strings, and arrays in Solidity?

solidity arrays bytes solidity-0.6.0 slice

modified Jan 8 at 21:49 shane 4,796

0

votes

1

answer

31

views

How to distinguish uint and int types during evm execution (via opcode)

go-ethereum evm overflow

modified Dec 30 '19 at 14:59 goodvibration 10.1k

-1

votes

1

answer

39

views

How can I get USDT Test Token [closed]

erc-20 ropsten

answered Jan 9 at 13:16 Jay 255

1

vote

0

answers

50

views

Obtaining pulledStates from Geth

go-ethereum state-trie

modified Jan 12 at 9:20 eth♦ 64.5k

0

votes

0

answers

50

views

Cant call solidity function from app.js?

solidity web3js truffle javascript

modified Jan 17 at 12:34 raghav 54

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