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1answer
94 views

Calling a smart contract function with an unsigned transaction

I'm new to working with Ethereum smart contracts and would appreciate some guidance by the community on a task that I'm trying to solve. This is the contract I want to use - https://github.com/chatch/...
0
votes
0answers
3 views

Executing the Truffle console script:Error: ENOENT: no such file or directory,

I am trying to execute the following script: module.exports = (callback)=> { Message.setProvider(web3.currentProvider); const MyContract = require("~/Truffle programs/...
2
votes
2answers
103 views

Solidity - Proper way to Import Contracts

When importing one Solidity contract into another, what’s the difference between importing it and accessing it using the is keyword, vs. importing it and just instantiating an object of it? Here’s ...
0
votes
1answer
127 views

how to use MEW, (not geth or mist) to use a private key to recover access to some ERC20 tokenss

I lost my jaxx backup phrase. I have private keys to two ERC20 tokens (ICN and SALT). I want to use MEW to regain access/link to my tokens on the blockchain. What are the exact steps in MEW to use ...
0
votes
0answers
5 views

RPC returns 0x0 after sync

binance smart chain v1.0.7 When new node complete syncing, RPC returns 0x0 values few hours.Can I fix that? Please help me
0
votes
2answers
47 views

Transaction reverted but not refunded

My transaction https://etherscan.io/tx/0xd4f9905b14e26ee96b243f47e734e1b7880dc2a23f8f847dae786fca0f3f9888 has failed and was marked as reverted 15 hours ago. Though i don't think my ETH wallet has ...
0
votes
0answers
3 views

Web3js works in my localhost NODE server but return an error in my remote webserver

All Web3js functions works correctly in my NODE (10.7.0) localhost server but the same configuration return the next error in my remote NODE webserver (same configuration and versions). Any idea? ...
0
votes
1answer
355 views

How to make this interact with metamask

I've been trying to make my contract be callable by metamask (so a popup will occur telling the user to confirm) but it does not seem to work, heres what I have come up with so far. Can anyone give me ...
1
vote
1answer
8 views

How to get same prices with Uniswap SDK & interacting directly with contract?

I am having difficulty understanding getting the price within the contract. So I created 2 different methods (one using SDK and other one using ethers.js) When I try the SDK, I get 3839.62 When I try ...
1
vote
1answer
5 views

Can ERC721Enumerable.sol provide an address's total set of NFT assets?

Intro: I am trying to use ERC721Enumerable in my NFT contract so I can get the set of all NFTs owned by a particular address. Research: The ERC721Enumerable contract was implemented to enumerate ...
0
votes
1answer
6 views

Get token standard type knowing the contract address and tokenId

How can I implement code that returns whether a token is in the ERC721 or ERC1155 standard, knowing both the contract address and the tokenId? What I tried is that I call a function that exists only ...
1
vote
1answer
8 views

ERC721 Conforming to Contract Standards

When implementing the ERC721 contract standard, how strictly does one have to stick to the naming conventions of the method signatures - as spelled out by the standard? Take for example the ownerOf ...
0
votes
1answer
26 views

How to send uint256 and Address types to Smart contract in JavaScript web3/ethers?

Im trying to send a query to Pancakeswap's router function getAmoutsOut here the code for importing the contract using ethers ABI: const router = new ethers.Contract('...
1
vote
1answer
2k views

How to transacting with a smart contract using web3j in Android?

i used web3j to Transacting with a smart contract. this is my Contract function which i want to intertact with. function usersRegister(string _id, string _password){ Equipment e = equipments[msg....
0
votes
0answers
7 views

How mining pools send transactions with 1gwei gas price?

Check this transaction, it is sent by a mining pool with 0.08$ fee, and it is almost mined with in minutes. How is this possible? Current average gas price is 150, that is almost 10$
0
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0answers
4 views

Function and withdrawal does not recognize the address as payable

I have this withdrawal function but an error happens: TypeError: "send" and "transfer" are only available for objects of type "address payable", not "address". -...
0
votes
1answer
685 views

”:ENCODING/HEX: ODD LENGTH HEX STRING” error sending ETH [will pay 1 ETH bounty]

When I try to send Ether I get an error code that says:ENCODING/HEX: ODD LENGTH HEX STRING. Here the history, my PC had had issues working properly so I did a system recovery, then rebooted Mist ...
0
votes
0answers
7 views

JSON-RPC error when deploying contract

I am really new into contracts and tokens, I wanted to learn how to deploy a contract, so I grabbed someone else's contract and tried to deploy it on BSC. I was following tutorial on youtube and ...
0
votes
0answers
3 views

get amount of transferred tokens from transaction receipt

Can someone explain to me how to get the amount of tokens that have been transfered from a transaction receipt? I came across some posts that said I can get it out of the data property from the ...
0
votes
2answers
18 views

Please Help. Fail with error 'Min return not reached'

Does anyone know how to solve this? This is the first time I use Metamask to swap ShibaInu, however it's failed. https://etherscan.io/tx/...
0
votes
1answer
12 views

What are some practical use cases of the fallback function?

Besides receiving ethers, for which there is a dedicated receive function, what is a practical use case of fallback? I can't think of a case when it would be desirable for a contract to execute a ...
6
votes
1answer
665 views

How to use Nodejs/Javascript and LevelUp to read Blocks from local geth database files (.ldb)?

Here's what I've been able to get going to far. I can open the blockchain database but I can't seem to create a valid blockchain object (nor call the blockchain.getBlock() function successfully). I'...
0
votes
0answers
3 views

web3 transaction value always 0

Can anyone explain to me, why the transaction object I receive via web3 always has a value of 0? When I open up the transactionhash in etherscan, it shows under the to field which is named "...
0
votes
0answers
4 views

Automatically tax transaction and distribute to all holder (Metamask, TrustWallet)

I was wondering if I e.g. use balanceOf(account[1]) += tax if the amount will also updated on Metamask and TrustWallet? Here is an example code which I found where the addresses will be in mapping and ...
3
votes
1answer
720 views

Regarding external file storage

Let's say you have a private blockchain, a DApp with an workflow to store and retrieve data from that blockchain. Now there is a need to store binary files and access it in a permissible way. One way ...
0
votes
0answers
6 views

Can I get price feed information directly from ChainLink oracles rather than from the aggregated contract?

I've been experimenting with ChainLink recently and am fascinated of what it can do. I already used the code provided here ChainLink Docs in Python and got it to work. However, I've been searching all ...
1
vote
1answer
12 views

error: { code: -32000, message: 'invalid sender' }

I'm trying to deploy my Smart Contract onto the Rinkeby test network. Everything is working fine, my rinkeby account is also having enough ethers. And also using HDWalletProvider, I am able to access ...
0
votes
0answers
10 views

Maintain two different token balances in a contract

How can we maintain the balances of two different bep-20 tokens in a single smart contract called Handler lets suppose? I am trying to write a function that transfers the second type and the first ...
1
vote
1answer
237 views

Ethereum Studio Won't Stay Open

I'm trying to open ethereum studio, but the tab closes a second after it opens. I've tried opening it through both chrome and edge.
0
votes
1answer
22 views

Passing an array to a function gets misinterpreted by the evm as value=20 causing INVALID_ARGUMENT error

I made an effort to cut out all the irrelevant parts of the code and get a minimal version still able to reproduce the error, these are the 3 smart contracts involved: // SPDX-License-Identifier: MIT ...
0
votes
2answers
119 views

Not able to get deployed address of smart contract

Error: connect ECONNREFUSED /home/sanya/.ethereum/geth.ipc at PipeConnectWrap.afterConnect [as oncomplete] (net.js:1106:14) errno: 'ECONNREFUSED', code: 'ECONNREFUSED', syscall: '...
-1
votes
1answer
11 views

RECOVERING USDC WITHDRAWN USING BINANCE SMART CHAIN

I am extremely new to crypto. I withdrew USDC to an address using the Binance Smart Chain Network. I have located the transaction on BscScan https://bscscan.com/token/...
0
votes
1answer
14 views

insufficient funds for intrinsic transaction cost

i've codded a script using js to trigger a buy on uniswap. the way i achieved this is through importing uniswaps smart contracts using this line of code: const router = new ethers.Contract(addresses....
0
votes
1answer
10 views

DeclarationError: Undeclared identifier while it's declared

I get "DeclarationError: Undeclared identifier" on _totalSuppy and _balances. Could anyone help me figure this out? Parent contract pragma solidity ^0.8.0; import "./IERC20.sol"; ...
4
votes
1answer
434 views

Storing private data off-chain with a sharing feature upon request

My question is not very technical from an implementation point of view, but I am looking for advice to achieve a specific use case using blockchain tech. I would greatly appreciate any insights or ...
-5
votes
1answer
54 views

Ethereum Classic Coins bought from https://classicetherwallet.com. I want to recover or transfer them to another wallet

I bought ETC via website https://classicetherwallet.com/ by generating the wallet in 2017. After that as the market went down. I was diverted and never looked into. However recently i came to know ...
0
votes
2answers
24 views

Exception:Reverted when swap by smart contrat with uniswap

Here is my code pragma solidity ^0.8.2; import "https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/interfaces/IUniswapV2Router02.sol"; contract Test_Swap{ address ...
1
vote
1answer
119 views

Token migration and IDEX smart contract problem

During a recent token migration from token A to token B, a large number of token A were held by a number of people in an IDEX address (where it was ready to trade). The IDEX address is part of a smart ...
0
votes
0answers
6 views

Linter Error: `assert(this.f.address == address(this));`

While learning solidity, I copy-pasted this code from: https://docs.soliditylang.org/en/v0.8.4/types.html // SPDX-License-Identifier: GPL-3.0 pragma solidity >=0.6.4 <0.9.0; contract Example { ...
0
votes
1answer
18 views

Constructor error on multiple pieces of code - Remix

I've been getting this error when I try and deploy a contract with a constructor on multiple pieces of code. I use the correct complier version too creation of MyContract errored: Error encoding ...
1
vote
1answer
70 views

Enable a download only for an NFT holder?

Could someone enable a download only for an NFT holder? What would be the mechanism for this?
1
vote
1answer
190 views

How are the stored transactions receipts referred from the block?

Based on the data structure of Ethereum blocks and transactions which is also represented here, we know the following sentences about the transactions receipts: 1- The transactions receipts are ...
2
votes
0answers
11 views

Do storage MPT branch nodes contain values?

when reading through the specs of Merkle-Patricia-Trees, I was wondering if branch nodes of storage tries ever contain values? It is my understanding, that the last array element of a branch node ...
0
votes
1answer
734 views

Claymore Miner With Multi GPUs

Issue: When I initiate "start.bat", I am noticing that the Miner only recognizes that I have (1) GPU being recognized. Although, I do have 6 of these cards all properly connected, powered on and ...
1
vote
1answer
95 views

Fail with error 'Min return not reached'

I am trying to make trades on 1inch and frequently get an error that reads Fail with error 'Min return not reached'. My gas prices are set very high because I need these trades to be as fast as ...
0
votes
0answers
4 views

Getting continuous warning in logs of my geth instance

Constantly getting logs like this in my geth instance WARN [05-08|14:06:32.143] Served eth_signTransaction conn=195.123.216.5:60142 reqid=1 t="83.324µs" err="tx fee (...
0
votes
0answers
8 views

tokenFallback and transferAndCall and approveAndCall?

Excuse me, What should data I pass in _data bytes when I call tokenFallback and transferAndCall and approveAndCall? function transferAndCall(address _recipient, uint256 _amount, bytes _data) function ...
0
votes
1answer
399 views

How to resolve Vyper installation error: fatal error: leveldb/db.h

Created a virtualenv with python3.6 and performed the following steps git clone https://github.com/ethereum/vyper.git cd vyper make I see following error(s): Downloading https://files.pythonhosted....
0
votes
0answers
8 views

How to send a fixed amount of ether to a smart contract from an account?

Is it possible to send a fixed amount of ether to smart contract from an account every time a function is executed or button is clicked? No input fields should be used.
0
votes
0answers
7 views

ERC-20 Token Transfer Error (Unable to locate corresponding Transfer Event Logs), Check with Sender

Token was created under ERC223. Every transfer that I have done received: ERC-20 Token Transfer Error (Unable to locate corresponding Transfer Event Logs), Check with Sender. Please help to check and ...

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