I am new to smart contracts and I am working on an Eth Rinkeby dapp and was wondering if anyone can tell me what the "16" means in this section: } network =
I have two smart contracts that I want to deploy. I want to deploy the first one, then pass the address of the first into the constructor of the second one. I a
I have a security problem in my Solidity contracts and I can't figure out how to fix it. The flow goes like this: First, we create an instance of contract A; Cr
use anchor_lang::prelude::*; declare_id!("Fg6PaFpoGXkYsidMpWTK6W2BeZ7FEfcYkg476zPFsLnS"); #[program] pub mod myepicproject { use super::*; pub fn start_st
I forked a contract, it is a Baked Beans fork on MATIC, I deployed the contract through Remix, now when I try to deposit through my website script, Metamask say
I am trying to send ETH to a contract function from a web app via metamask and ethers.js. So far I have tried: const provider = new ethers.providers.Web3Provide
i have the abi json file for a contract and i want to use its functions in my smart contract. is there any way to do it? for example i have a contractA.sol and
I am working on a dapp that needs to verify users' signatures. When testing with Metamask, everything is okay. When trying to verify a signature from Ambire wal
I want to build an NFT that I can paid with an ERC-20 token to mint it. I'm using currently the Mumbai testnet on polygon, and I'm using the Dummy ERC20 token t
I am trying to write a smart contract and line 1 is bringing up an error : ParserError: Found version pragma, but failed to parse it. Please ensure there is a
I am trying to deploy my SimpleStorage.sol contract to a ganache local chain by making a transaction using python. It seems to have trouble connecting to the ch
I am discovering the blockchain world step by step, but I am facing a problem that I can't solve. I am using this simple smart contract from the Solidity docume
Smart contract execution needs gas fee. So all data can't be stored in blockchain. Images could be stored on ipfs like Pinata. Do I have to develop extra backen
If a smart contract has the compiled bytecode for a contract can the first deploy a subsequent contract? According to Ethereum.org: "To deploy a smart contract,
Solifity 0.8.0 with struct struct Placeholder{ string a; uint256 b; } mapping(uint256 => Placeholder[]) public placeholder; why this error Member "b" no
I'm trying to create my own NFT contract factory, but it fails in mainnet. I have ETH on my wallet. In test it works fine. Here's my contract: //Contract based
I'm using node version 12.20.2 and npm version 6.14.11 and installed truffle with cmd as administrator, the truffle framework version 5.5.12 has been installed
I am looking to grab historical data from our Solana Devnet feeds. Can you let me know if get_submissions is the function that should be called for historical d
I get this error where I run anchor deploy: Deploying workspace: http://127.0.0.1:8899 Upgrade authority: /home/<user>/.config/solana/id.json Deploying pr
2_deploy_contracts.js ===================== Replacing 'SimpleStorage' ------------------------- Error [ERR_UNHANDLED_ERROR]: Unhandled error. ({ code: