Solidity 单位

1. Ether

Ether的单位关键字有wei, gwei, finney, szabo, ether,换算格式如下:

  • 1 ether = 1 * 10^18 wei
  • 1 ether = 1 * 10^9 gwei
  • 1 ether = 1 * 10^6 szabo
  • 1 ether = 1* 10^3 finney

示例:

pragma solidity 0.4.20;
/**
 * 对 比特币 Ether 的几个单位进行测试
 */
contract testEther {
    // 定义全局变量
    uint public balance;

    function testEther() public{
        balance = 1 ether;  //1000000000000000000
    }

    function fFinney() public{
      balance = 1 finney; //1000000000000000
    }

    function fSzabo() public{
      balance = 1 szabo;  //1000000000000
    }

    function fWei() public{
      balance = 1 wei; //1
    }
}

 

2. Time

Time的单位关键字有seconds, minutes, hours, days, weeks, years,换算格式如下:

  • 1 == 1 seconds
  • 1 minutes == 60 seconds
  • 1 hours == 60 minutes
  • 1 days == 24 hours
  • 1 weeks == 7 days
  • 1 years == 365 days

如果你需要进行使用这些单位进行日期计算,需要特别小心,因为不是每年都是365天,且并不是每天都有24小时,因为还有闰秒。由于无法预测闰秒,必须由外部的oracle来更新从而得到一个精确的日历库(内部实现一个日期库也是消耗gas的)。

示例:

pragma solidity 0.4.20;
/**
 * 对 Time 单位进行测试
 */
contract testTime {

    // 定义全局变量
    uint time;

    function testTime() public{
      time = 100000000;
    }

    function fSeconds() public view returns(uint){
      return time + 1 seconds; //100000001
    }

    function fMinutes() public view returns(uint){
      return time + 1 minutes; //100000060
    }

    function fHours() public view returns(uint){
      return time + 1 hours; //100003600
    }

    function fWeeks() public view returns(uint){
      return time + 1 weeks; //100604800
    }

    function fYears() public view returns(uint){
      return time + 1 years; //131536000
    }
}

constant、view 和 pure 三个修饰词有什么区别和联系?简单来说,在Solidity v4.17之前,只有constant,后来有人嫌constant这个词本身代表变量中的常量,不适合用来修 ...