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  • Jun 05 2016 10:31
    @alexvandesande banned @adamskee
  • Mar 16 2016 01:12
    @alexvandesande banned @scbosse
Akshay Dev H
Hi, i have used the functions from ,, it deploys perfectly, but returns an error "the constructor should be payable, if you send value" message while attempting to buy tokens using ether (in Java Script VM) . I have also made the constructor function payable.. still it returns error :(
Where would be the best place to get help on deploying a token regarding myetherwallet? I've choked out something that I suspect was malformed and can't afford to make that mistake again.
Hi all , how to get all the blocks transaction like as etherscan.api based on ethereum address , plz help me to solve
How can we get transaction details from ethereum address using web3 its getting slow any other solution that would get result fast.Like etherscan api??
hi all, i am trying to create an account but for hours seeing generating account... any clue?
Melvin Olive
Hello all I am trying to raise funds for my startup via etherium crowd sale.
in the amount of 2000000 USD
Hello everyone,
can anyone please help to sort out my problem,
Actually i want to use one instance of my token contract in many other contract (different contracts for differnt type of people like advisors , developers).
If anyone knows , please help me
Myles MacGregor
When I try to develop a new contract, why is the line "function MyToken(...)" wrong?
How do we deal with this error : Defining constructors as functions with the same name as the contract is deprecated. Use "constructor(...) { ... }" instead.
I am new to ethereum and need some help with this
Hey guys, how can I verify the contract on etherscan?
The reason of this warning is that : in latest version of solidity , constructor function should defined with the keyword constructor not with the name of the
Thanks @anuragLHT

So Now function myContract () {

willl b something like constructor myContract () {



Will it be used this way
@sahni619 no just write constructor (arguments) , nothing else
ok. thanks @anuragLHT
Akshay Dev H
@MPA-MRK just use constructor(....) instead of function MyToken(...)
Akshay Dev H
@AboShanab click on the verify and publish link ...then copy paste your entire smart contract code,,,, Ensure that the compiler version must be same as that used for deploying the contract. also you should check the optimization option ..
hello guyz
i am building one website for blood bank. i want to build it on blockchain using ethereum.
i am building 2 contracts where one i used to store blood bank information and blood quota
and 2nd contract is for calculating storing total blood bank quota
can any one suggest contract structure for this
i just upload the code which i did

pragma solidity ^0.4.19;

import "./BloodQuota.sol";

contract BloodBank is BloodQuota {

string bloodBankName;
string bloodBankAddress;
string bloodBankemail;
address centralBankAddress;

function setCentralBankAddress(address _address) public {
centralBankAddress = _address;

modifier onlyOwner(string _bloodBankName) {
require(keccak256(bloodBankName) == keccak256(bloodBankName)); ;

function addOrganization( string _organizationName, string _organizationAddress,
string _email,
uint128[8] _bloodQuota
) public {
updateBloodBankQuota(centralBankAddress, _bloodQuota);

function organizationDetails() public view returns (string, string, string) {
return (bloodBankName, bloodBankAddress, bloodBankemail);

function updateBloodQuota (string _bloodBankName , uint128[8] _bloodQuota )
public onlyOwner(_bloodBankName){
updateBloodBankQuota(centralBankAddress, _bloodQuota);

pragma solidity ^0.4.19;
import "./TotalBloodQuotaAvailable.sol";

contract BloodQuota {
uint128 aPos=0;
uint128 aNeg=0;
uint128 bPos=0;
uint128 bNeg=0;
uint128 oPos=0;
uint128 oNeg=0;
uint128 abPos=0;
uint128 abNeg=0;

function updateBloodBankQuota(address _centralBankAddress, uint128[8]  _bloodQuota) public   {
  TotalBloodQuotaAvailable CB = TotalBloodQuotaAvailable(_centralBankAddress);
  CB.updateQuota(_bloodQuota , [aPos, aNeg, bPos, bNeg, oPos, oNeg, abPos, abNeg]);
  aPos = _bloodQuota[0];
  aNeg = _bloodQuota[1];
  bPos = _bloodQuota[2];
  bNeg = _bloodQuota[3];
  oPos = _bloodQuota[4];
  oNeg = _bloodQuota[5];
  abPos = _bloodQuota[6];
  abNeg = _bloodQuota[7];

 function getBloodBankQuota() public view returns (uint128 aPositive,
 uint128 aNegative, uint128 bPositive, uint128 bNegative, uint128 oPositive,
 uint128 oNegative, uint128 abPositive, uint128 abNegative) {
     // return quota from blood bank
     return(aPos, aNeg, bPos, bNeg, oPos, oNeg, abPos, abNeg);


Biky Chowhan
provide the some documentation based on Decentralise smart contract using ethereum
Itamar Levy-Or

Hi I am new to ethereum, and solidity. I am starting by following this tutorial: it seems to be a little out of date. Does anybody have a suggestion as to an alternative? Additionally when trying to use the commend: truffle migrate. I get the following error:

2_deploy_contracts.js invalid or does not take any parameters

Thanks for the help.

Akshay Dev H
@ItamarLevyOr try using constructor () public {
candidate = "Candidate 1" instead of function Election () public {
candidate = "Candidate 1"
hello admin
hi i just want code for erc721
Mayank Sahai
@anuragLHT yes?
Germán Lugo
Hi every body!! I'm looking for a good tutorial of drizzle. The documentation is still to hard for me.
Hi, when I åaste the ERC20 token pragma solidity 4.16 complete script from in Ethereum wallet deploy contract, it says there are errors in script. Do you know standard ERC20 token script that compiles in wallet 0.11.1 ?
Hi, when I paste the ERC20 token pragma solidity 4.16 complete script from in Ethereum wallet deploy contract, it says there are errors in script. Do you know standard ERC20 token script that compiles in wallet 0.11.1 ?
Does any dpos consensus engine in go-ethereum ?
Hey there. I am bloody new to Ethereum and struggling with the Constructor/function thing when creating a Contract. I just read only to use the Constructor. But as i'm using the variable 'initialSupply' as in the tutorial recommended, initialSupply is unknown. So how do i declare the variable without the function? And where is the benefit for not hardcoding it?
Germán Lugo
Hi @AlexanderWelling what are you using to deploy your contract? Truffle o Remix?
You could hardcode without any problem or any consequence of any kind. Even, when you are doing test is maybe the most practical thing if you are in Remix. You don't have to pass argument for each deployment.
Then for elegance maybe people or when people share a contract as template, they create a contract with a constructor that take parameters.
Paul Nguyen
Thanks for connecting me and care.I don’t know know so much about
Thank you @Chococoin for responding, I'm using none of them. I just wrote it in the Ethereum Wallet Software for learning purposes. But i suppose i will switch on Truffle when things become more serious.
Venkata Vineel
Folks , what type of apps can we make with this platform
Venkata Vineel
Does Blockchain have any relevance to small businesses
function send(address receiver, uint amount) public {
if (balances[msg.sender] < amount) return;
hi if balances of sender is less than amount then it says to return.. Can any one explain this ?
I think no one helps the newbies here :(
@sahni619 This means if you try to send amount more than balance, then it will terminate without any exchange. For newbies tutorials, please take a look here :
interface tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData) external; }
Is this interface another contract?