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  • Jun 05 2016 10:31
    @alexvandesande banned @adamskee
  • Mar 16 2016 01:12
    @alexvandesande banned @scbosse

Hi There is a person to answer the question here

Is it?

HI All can any one give me link to understand basic of bitcoin etc.. Jumping into technical gives me tough time to understand the concepts
davoud vakili
very thanks
in this bout you can doing two work:
1) - or going to the metamask part to the test
davoud vakili
2)- you can going to the ether wallet and going to the part test
is there anyone tole me about creating account implemented
Anubhav Gupta
I have a requirement where we need to save data(pdf) to blockchain so that any third party can access and view it later by the block address. I can't store the hash of the data on blockchain as the third party does not have access to the original document to verify the hash of the data. Is it feasible?
Deep Vora
I'd say its not feasible, as storing data on blockchain is really expensive
also if you end up doing that, encrypt your file before storing on blockchain

We can create ERC20 tokens using solidity or even metamask.. but how to create unique address to transfer them?

I mean token like Gold reward or coins like Bitconnect has it's own pattern of address to transfer in between. how to do that?

In HitBTC also for every token you will get unique address to send..

if is there any way to do this, need to do that during the contract deployment or can be done after creating the simple token ?

Akshay Dev H
Hi, i have used the functions from https://www.ethereum.org/token ,, 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: http://www.dappuniversity.com/articles/the-ultimate-ethereum-dapp-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 ethereum.org/token 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 ethereum.org/token 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 ?