Hottest Questions This Month

2

votes

2

answers

196

views

Should I set GasPrice on my own?

web3js

modified Jun 13 at 8:27 rw026 159

4

votes

1

answer

111

views

What are the odds of getting same address or private-key or 12/24 set of mnemonic to 2 different people

answered Jun 21 at 18:57 Morten 726

3

votes

1

answer

88

views

Can chaindata be split across two (or more) locations?

go-ethereum nodes clients chaindata

answered Jun 23 at 7:19 eth♦ 66.2k

1

vote

1

answer

133

views

How to get all kind of transactions happend to/from an address within a time range?

web3js transactions metamask etherscan internal-transactions

modified Jun 25 at 12:58 Lauri Peltonen 11.5k

0

votes

2

answers

131

views

Swap tokens back to ether on Uniswap V2 Router 02 (Sell tokens)

solidity uniswap

modified Jun 30 at 22:44 gbenroscience 143

4

votes

1

answer

73

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Why do I need decentralized oracles?

blockchain oracles external-api

modified Jul 1 at 16:53 Patrick Collins 372

2

votes

1

answer

92

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Efficient, safe pow using EXP opcode

opcode safemath

modified 2 days ago goodvibration 15.4k

5

votes

1

answer

51

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How to catch a `revert()` error using Brownie?

revert-opcode brownie

modified Jun 14 at 9:35 alper 6,171

4

votes

2

answers

76

views

Graph traversals on Ethereum, at scale

solidity contract-design design-patterns graphs

answered Jun 14 at 20:16 Alberto Cuesta Cañada 21

1

vote

1

answer

82

views

Is there any way to avoid calling these 2 separate transactions?

solidity transactions

modified Jul 3 at 7:50 Mikko Ohtamaa 10.9k

2

votes

2

answers

63

views

web3.eth.sendSignedTransaction is not returning promise or promised event emiter

web3js sendsignedtransaction

modified Jun 22 at 20:18 Ismael 21.2k

2

votes

1

answer

59

views

What's mean Solidity instruction: “this;” alone?

solidity

modified Jun 27 at 14:32 goodvibration 15.4k

3

votes

1

answer

53

views

How to create private key from mnemonic and extra-word using web3

web3js myetherwallet mnemonic

modified Jun 15 at 10:24 Morten 726

2

votes

1

answer

64

views

Solidity ^0.6.0 Truffle Compile Error: Cannot read property … of undefined

solidity truffle-compile solidity-0.6.x

modified Jun 22 at 18:18 Mikko Ohtamaa 10.9k

0

votes

2

answers

35

views

what address(0) means? more specific where those token go?

solidity remix

answered Jun 17 at 19:07 goodvibration 15.4k

2

votes

2

answers

43

views

Explain delete_element For loop

solidity

modified Jun 25 at 10:40 Masoud jt 455

1

vote

1

answer

52

views

Ethereum Error: Provider does not support subscriptions: HDWalletProvider

web3js truffle nodejs truffle-hdwallet-provider

modified Jun 25 at 15:54 gbenroscience 143

0

votes

1

answer

61

views

Swap ether to tokens on Uniswap V2 Router 02 fails

solidity web3js truffle

modified Jul 4 at 11:28 gbenroscience 143

3

votes

1

answer

47

views

Do we have 'null' keyword in solidity?

solidity solidity-0.6.x

answered Jun 13 at 13:42 Haseeb Saeed 378

0

votes

1

answer

36

views

How does Smart-contract's storage works?

contract-development contract-deployment storage

modified Jun 13 at 16:04 Haseeb Saeed 378

1

vote

2

answers

58

views

How to get reason revert using web3.eth.call

go-ethereum web3js revert-opcode require eth-call

answered Jun 26 at 8:24 Markus - soliditydeveloper.com 1,002

0

votes

1

answer

45

views

How to build an Ethereum hot wallet for an exchange

web3js tokens ether erc-20 exchanges

modified Jul 3 at 8:10 Mikko Ohtamaa 10.9k

2

votes

1

answer

32

views

Is the May 2017 contract creation attack still possible?

contract-design contract-deployment gas security attacks

answered Jun 25 at 19:00 Ismael 21.2k

0

votes

2

answers

51

views

How to get list of transaction for ERC20 token address?

etherscan

answered Jun 15 at 5:59 AD95 1

0

votes

1

answer

50

views

Transfer money between contracts

remix contract-design address.transfer receive

answered Jun 23 at 4:07 Ismael 21.2k

0

votes

2

answers

63

views

How do I give every user Ethereum an address and does it affect security

solidity contract-development remix contract-design addresses

answered Jun 24 at 7:03 toothleth_byte 146

0

votes

2

answers

29

views

High Gas Cost for Factory Contract!

solidity contract-development factory

answered Jul 4 at 2:02 Markus - soliditydeveloper.com 1,002

0

votes

1

answer

46

views

[question deleted because not relevant] [closed]

go-ethereum

modified Jun 14 at 7:39 U.zhang 1

1

vote

1

answer

46

views

In Solidity, Is there any situation, when string is necessary?

solidity string bytes bytes32

modified Jun 29 at 8:34 goodvibration 15.4k

2

votes

1

answer

35

views

What is the network layer in which RLPx is used for peering in Ethereum

go-ethereum peers devp2p rlpx

answered Jun 9 at 6:27 Masoud jt 455

0

votes

1

answer

27

views

How to forward tokens without paying a gas

contract-development wallets address.transfer

answered Jul 4 at 9:51 Mikko Ohtamaa 10.9k

0

votes

2

answers

55

views

Solidity 0.4.26 check if element already exists in array

arrays mapping struct

modified Jun 11 at 18:45 Giuseppe Bertone 2,591

0

votes

0

answers

54

views

Get the txHash,but on etherscan I get “Sorry, We are unable to locate this TxnHash”?

solidity web3js

asked Jul 1 at 16:26 heyooo12 1

1

vote

1

answer

42

views

How to send signed transaction to blockchain from different account

web3js gas-price sendsignedtransaction

modified Jun 12 at 12:49 Haseeb Saeed 378

0

votes

1

answer

42

views

In Solidity, what's the difference between funtion type and funtion? [closed]

solidity

answered Jul 2 at 8:56 AvocadoChocolate 83

1

vote

0

answers

53

views

Solidity function calls from javascript work locally but fail on ropsten,kovan etc with Error: Returned values aren't valid, did it run Out of Gas?

solidity truffle blockchain javascript nodejs

modified Jun 18 at 11:28 gbenroscience 143

3

votes

1

answer

32

views

Brownie cannot install solc on OSX

contract-development python brownie

modified Jun 10 at 11:00 iamdefinitelyahuman 1,623

1

vote

1

answer

32

views

How can i create my own version of Metamask? (Wallet, provider and a signer)

web3js blockchain metamask

answered Jun 22 at 13:02 Lauri Peltonen 11.5k

0

votes

1

answer

40

views

Fundamental question! (HD Wallet private key hacked) [closed]

ethereum-wallet-dapp private-key mnemonic

answered Jun 25 at 5:52 Masoud jt 455

0

votes

1

answer

31

views

How can we lock ETH in user wallet without escrow contract?

ether wallets ethereum-wallet-dapp myetherwallet gambling

answered Jun 30 at 3:10 Markus - soliditydeveloper.com 1,002

0

votes

1

answer

39

views

Uniswap V2 smart contract keeps getting reverted in JS

solidity dapps javascript uniswap

answered Jun 27 at 3:55 Markus - soliditydeveloper.com 1,002

2

votes

1

answer

30

views

Is “type” a reserved keyword in Solidity?

solidity solidity-0.6.x

modified Jun 10 at 22:14 shane 6,194

0

votes

2

answers

30

views

Does any such smart contract exist where the creator's private key is not required at the time of unlocking?

contract-development

answered Jun 26 at 3:52 Rob Hitchens 39.6k

0

votes

1

answer

38

views

How to implement ether transfer from one EOA to another using a contract?

solidity go-ethereum web3js truffle-contract

modified Jun 15 at 7:34 Vikas Mujumdar 3

0

votes

0

answers

48

views

How do i withdraw Eth from a contract i created

transactions contract-design metamask myetherwallet

asked Jul 2 at 12:12 Soupdragon 1

0

votes

1

answer

47

views

How to estimate gas limit for “payable” smart contract?

web3js gas-limit

answered Jun 16 at 13:14 Joncarre 1

0

votes

1

answer

47

views

where to host my react fornt end and express endpoint that interact with smart contract to be fully decentralised?

solidity dapp-development ethereumjs react decentralization

answered Jun 26 at 10:06 clement 91

1

vote

1

answer

35

views

WebSocket connection dropped in Web3.js with Infura

web3js infura

modified Jun 13 at 7:01 Mikko Ohtamaa 10.9k

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