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  • Jun 05 2016 10:31
    @alexvandesande banned @adamskee
  • Mar 16 2016 01:12
    @alexvandesande banned @scbosse
hello, please Is it too late to swap my OLD ERC20 token to the New one? please anyone?

Hi, Im looking to understand ERC2 tokens a little better.
Could someone explain to me how Token Bonuses are actually managed?

If there is an exchange rate within the smart contract, how do you get around it and offer, say, 20% or 50% bonus, as most ICOs do?

how do I update a smart contract and assign a new administrator ?
Does anyone have any tutorials?
Data Guru
@eryssonbarros sorry if my suggestion looks childish but can you not create a function to make new msg sender as the owner and take old contract into new one using inheritance etc
@eryssonbarros That a look at the Ownable and Claimable contracts from OpenZeppelin. https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/ownership/Claimable.sol
@phiferd ok i go to see
Navneet Boghani
web3.eth.sendTransaction not send my balance
load log time
I m using main net of ETC
web3.eth.sendTransaction({from:adminAddress, to:sendaddress,value:send_amount,gas:gaslimit,gasPrice:getGasPrice},function(trasn_err,txid){
// console.log('amount send');
} else {
hi every one
im new here i Need help please, i want to make my own alter coin
  1. Name coin Oha Coin
  1. nummer supply 100.000.000
and People can minning 50.000.000
please help

pragma solidity ^0.4.16;

interface tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData) external; }

contract TokenERC20 {
// Public variables of the token
string public name;
string public symbol;
uint8 public decimals = 18;
// 18 decimals is the strongly suggested default, avoid changing it
uint256 public totalSupply;

// This creates an array with all balances
mapping (address => uint256) public balanceOf;
mapping (address => mapping (address => uint256)) public allowance;

// This generates a public event on the blockchain that will notify clients
event Transfer(address indexed from, address indexed to, uint256 value);

// This generates a public event on the blockchain that will notify clients
event Approval(address indexed _owner, address indexed _spender, uint256 _value);

// This notifies clients about the amount burnt
event Burn(address indexed from, uint256 value);

 * Constructor function
 * Initializes contract with initial supply tokens to the creator of the contract
function TokenERC20(
    uint256 initialSupply,
    string tokenName,
    string tokenSymbol
) public {
    totalSupply = initialSupply * 10 ** uint256(decimals);  // Update total supply with the decimal amount
    balanceOf[msg.sender] = totalSupply;                // Give the creator all initial tokens
    name = tokenName;                                   // Set the name for display purposes
    symbol = tokenSymbol;                               // Set the symbol for display purposes

 * Internal transfer, only can be called by this contract
function _transfer(address _from, address _to, uint _value) internal {
    // Prevent transfer to 0x0 address. Use burn() instead
    require(_to != 0x0);
    // Check if the sender has enough
    require(balanceOf[_from] >= _value);
    // Check for overflows
    require(balanceOf[_to] + _value >= balanceOf[_to]);
    // Save this for an assertion in the future
    uint previousBalances = balanceOf[_from] + balanceOf[_to];
    // Subtract from the sender
    balanceOf[_from] -= _value;
    // Add the same to the recipient
    balanceOf[_to] += _value;
    emit Transfer(_from, _to, _value);
    // Asserts are used to use static analysis to find bugs in your code. They should never fail
    assert(balanceOf[_from] + balanceOf[_to] == previousBalances);

 * Transfer tokens
 * Send `_value` tokens to `_to` from your account
 * @param _to The address of the recipient
 * @param _value the amount to send
function transfer(address _to, uint256 _value) public returns (bool success) {
    _transfer(msg.sender, _to, _value);
    return true;

 * Transfer tokens from other address
 * Send `_value` tokens to `_to` on behalf of `_from`
 * @param _from The address of the sender
 * @param _to The address of the recipient
 * @param _value the amount to send
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
    require(_value <= allowance[_from][msg.sender]);     // Check allowance
    allowance[_from][msg.sender] -= _value;
    _transfer(_from, _to, _value);
    return true;

 * Set allowance for other address
 * Allows `_spender` to spend no more than `_value` tokens on your behalf
 * @param _spender The address authorized to spend
 * @param _value the max amount they can spend
function approve(address _spender, uint256 _value) public
    returns (bool success) {
    allowance[msg.sender][_spender] = _value;
    emit Approval(msg.sender, _spender, _value);
    return true;

 * Set allowance for other address and notify
 * Allows `_spender` to spend no more than `_
what do i Need to change
Navneet Boghani
block count is not running for ETC in GETH
so can you tell me whats problem
how can i resolved it?
Has anyone ever build Universal wallet?
why does this have a hold on create me and wallet. and this is stopping a lot of my projects i believe
don't make a dime sure not donating nothing
hello everyone;
what is the safest way to issu the contract?
i have question for crate own coin use erc 20
i'm send own coin to other wallet but use ether fee
how to send own coin by use own coin fee
Hi, someone send me a completed code please? i always get error when i use code on ethereum.org
Anyone , I need help with ethereum
Kindly contact eth@consultant.com for rectification
Hi Guys, New tutorials for Solidity are available here : https://www.youtube.com/playlist?list=PLL5pYVd8AWtT6vcvLo6vHv3EmtsqiQBxy
davoud vakili
my name is ERIC from china, very glad to be here
I need some information or method about eth testing, please send to me. ths
Hello all
I am unable to see constructer parameters as soon as a define a contract.. can anyone help. I am new to etherium
i see so many questions who answers them?

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