介绍 Okuru 令牌

简介

Okuru 令牌是一种基于区块链技术的数字加密货币，它支持任何认证交易并在其平台上进行结算。Okuru 令牌是以太坊智能合约的代币，也支持以太坊钱包。

技术细节

Okuru 令牌使用 Solidity 语言编写的智能合约作为支持平台，通过以太坊区块链技术来实现帐户之间的交换，每个交易都记录在区块链上，并可通过区块链浏览器进行查询。Okuru 令牌符合 ERC20 标准，支持与其他 ERC20 令牌进行交换。

功能特点

• 安全：Okuru 令牌使用了最先进的区块链加密技术，确保在平台上的交易安全；
• 去中心化：采用去中心化设计，避免了中心化风险和单点故障，可保证完全的透明度和公正性；
• 全球性：Okuru 令牌不受地理位置和国界的限制，全球范围内可以自由、无障碍地使用；
• 高效：Okuru 令牌支持高效的交易处理和结算，没有传统支付方式的繁琐流程和限制。

代码示例

pragma solidity ^0.5.0;

import "./IERC20.sol";
import "./SafeMath.sol";

contract OkuruToken is IERC20 {
  using SafeMath for uint256;

  string public constant name = "Okuru Token";
  string public constant symbol = "OKR";
  uint8 public constant decimals = 18;
  uint256 public constant totalSupply = 1000000000 * (10 ** uint256(decimals));

  mapping (address => uint256) private _balances;
  mapping (address => mapping (address => uint256)) private _allowed;

  constructor() public {
    _balances[msg.sender] = totalSupply;
    emit Transfer(address(0), msg.sender, totalSupply);
  }

  function balanceOf(address owner) public view returns (uint256) {
    return _balances[owner];
  }

  function allowance(address owner, address spender) public view returns (uint256) {
    return _allowed[owner][spender];
  }

  function transfer(address to, uint256 value) public returns (bool) {
    require(to != address(0));
    require(value <= _balances[msg.sender]);

    _balances[msg.sender] = _balances[msg.sender].sub(value);
    _balances[to] = _balances[to].add(value);
    emit Transfer(msg.sender, to, value);
    return true;
  }

  function approve(address spender, uint256 value) public returns (bool) {
    _allowed[msg.sender][spender] = value;
    emit Approval(msg.sender, spender, value);
    return true;
  }

  function transferFrom(address from, address to, uint256 value) public returns (bool) {
    require(to != address(0));
    require(value <= _balances[from]);
    require(value <= _allowed[from][msg.sender]);

    _balances[from] = _balances[from].sub(value);
    _balances[to] = _balances[to].add(value);
    _allowed[from][msg.sender] = _allowed[from][msg.sender].sub(value);
    emit Transfer(from, to, value);
    return true;
  }

  function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
    _allowed[msg.sender][spender] = (_allowed[msg.sender][spender].add(addedValue));
    emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
    return true;
  }

  function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
    uint256 oldValue = _allowed[msg.sender][spender];
    if (subtractedValue >= oldValue) {
        _allowed[msg.sender][spender] = 0;
    } else {
        _allowed[msg.sender][spender] = oldValue.sub(subtractedValue);
    }
    emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
    return true;
  }
}

以上是示例代码，实现了关于 Okuru 令牌的 ERC20 标准接口，包括转账、授权、查询余额等功能。实际使用中，可以根据需求进行适当修改并部署在以太坊上。