Very Simple ERC-20 Smart Contract on the Ethereum Blockchain, with many customizable Options to create a useable Cryptocurrency.
Ready to deploy Ethereum Smart Contract
The Example Smart Contract is already filled with values, the only thing you need to do is to customize these values with the attributes you want for your Cryptocurrency look at the Example below: ⬇️⬇️⬇️
function Robot(){
// Give the creator all initial tokens (100000000000000000000000000 for example)
balances[msg.sender] = 100000000000000000000000000;
// Update total supply (100000000000000000000000000 for example)
totalSupply = 100000000000000000000000000;
// Set the name for display purposes
name = "Robot";
// Amount of decimals for display purposes
decimals = 18;
// Set the symbol for display purposes
symbol = "RBT";
}
These are the only attributes you need to change in the Smart Contract, to customize your Cryptocurrency and then you can already deploy your Smart Contract on the Ethereum Blockchain. 💎
Tip: The created Cryptocurrency goes into the wallet where the Smart Contract was deployed.
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pragma solidity ^0.4.4;
contract Token {
/// @return total amount of tokens
function totalSupply() constant returns (uint256 supply) {}
/// @param _owner The address from which the balance will be retrieved
/// @return The balance
function balanceOf(address _owner) constant returns (uint256 balance) {}
/// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transfer(address _to, uint256 _value) returns (bool success) {}
/// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {}
/// @notice `msg.sender` approves `_addr` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of wei to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _value) returns (bool success) {}
/// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent
function allowance(address _owner, address _spender) constant returns (uint256 remaining) {}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}
contract StandardToken is Token {
function transfer(address _to, uint256 _value) returns (bool success) {
//Default assumes totalSupply can't be over max (2^256 - 1).
//If your token leaves out totalSupply and can issue more tokens as time goes on, you need to check if it doesn't wrap.
//Replace the if with this one instead.
//if (balances[msg.sender] >= _value && balances[_to] + _value > balances[_to]) {
if (balances[msg.sender] >= _value && _value > 0) {
balances[msg.sender] -= _value;
balances[_to] += _value;
Transfer(msg.sender, _to, _value);
return true;
} else { return false; }
}
function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
//same as above. Replace this line with the following if you want to protect against wrapping uints.
//if (balances[_from] >= _value && allowed[_from][msg.sender] >= _value && balances[_to] + _value > balances[_to]) {
if (balances[_from] >= _value && allowed[_from][msg.sender] >= _value && _value > 0) {
balances[_to] += _value;
balances[_from] -= _value;
allowed[_from][msg.sender] -= _value;
Transfer(_from, _to, _value);
return true;
} else { return false; }
}
function balanceOf(address _owner) constant returns (uint256 balance) {
return balances[_owner];
}
function approve(address _spender, uint256 _value) returns (bool success) {
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
return true;
}
function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
return allowed[_owner][_spender];
}
mapping (address => uint256) balances;
mapping (address => mapping (address => uint256)) allowed;
uint256 public totalSupply;
}
//name this contract whatever you'd like
contract Robot is StandardToken {
function () {
//if ether is sent to this address, send it back.
throw;
}
/* Public variables of the token */
/*
NOTE:
The following variables are OPTIONAL vanities. One does not have to include them.
They allow one to customise the token contract & in no way influences the core functionality.
Some wallets/interfaces might not even bother to look at this information.
*/
string public name; //fancy name: eg Simon Bucks
uint8 public decimals; //How many decimals to show. ie. There could 1000 base units with 3 decimals. Meaning 0.980 SBX = 980 base units. It's like comparing 1 wei to 1 ether.
string public symbol; //An identifier: eg SBX
string public version = '1.1.3'; //human 0.1 standard. Just an arbitrary versioning scheme.
//
// CHANGE THESE VALUES FOR YOUR TOKEN
//
//make sure this function name matches the contract name above. So if you're token is called TutorialToken, make sure the //contract name above is also TutorialToken instead of ERC20Token
function Robot(
) {
balances[msg.sender] = 100000000000000000000000000; // Give the creator all initial tokens (100000 for example)
totalSupply = 100000000000000000000000000; // Update total supply (100000 for example)
name = "Robot"; // Set the name for display purposes
decimals = 18; // Amount of decimals for display purposes
symbol = "RBT"; // Set the symbol for display purposes
}
/* Approves and then calls the receiving contract */
function approveAndCall(address _spender, uint256 _value, bytes _extraData) returns (bool success) {
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
//call the receiveApproval function on the contract you want to be notified. This crafts the function signature manually so one doesn't have to include a contract in here just for this.
//receiveApproval(address _from, uint256 _value, address _tokenContract, bytes _extraData)
//it is assumed that when does this that the call *should* succeed, otherwise one would use vanilla approve instead.
if(!_spender.call(bytes4(bytes32(sha3("receiveApproval(address,uint256,address,bytes)"))), msg.sender, _value, this, _extraData)) { throw; }
return true;
}
}
