I got this error during migration in truffle. : ParserError: Expected ‘(‘ but got identifier

This is my smartcontract code pragma solidity ^0.5.0; contract DappToken{ uint256 public totalSupply; constructor DappToken() public{ totalSupply = 10000; } } This is code for migration in truffle. const Dapptoken = artifacts.require(“DappToken.sol”); module.exports = function(deployer) { deployer.deploy(Dapptoken); Blockquote };

Is there a way to deploy a contract using bytecode only (to Ropsten …)?

One solution on medium.com describes how to do that via myetherwallet but it’s the old verion of myetherwallet where you can switch between ropsten/mainnet – right now I can’t find how to switch to ropsten… I’ve deployed on ropsten with both remix and truffle but both required .sol solidity sourcecode and not bytecode? Thanx!

i am try to call a method in solidity smart contract through angular app. but i unable to call the method. this is the error i get in console

i am try to call a method in solidity smart contract through angular app. but i unable to call the method. can someone please help me. this is the error i get in console TypeError: this.contract.methods.hello is not a function at CertificateContractService.<anonymous> (certificate-contract.service.ts:32) at Generator.next (<anonymous>) at fulfilled (tslib.es6.js:70) at ZoneDelegate.invoke (zone-evergreen.js:359) at Object.onInvoke (core.js:39699)…

In PoS, why does a block header need to be signed by the miner?

I am reading the following article about PoS http://earlz.net/view/2017/07/27/1904/the-missing-explanation-of-proof-of-stake-version In this article, the author says The block hash must be signed by the public key in the staking transaction’s second vout Why is this necessary? I understand that in PoW there is no need to sign the block because there is no transaction that consumes…