now變量可以返回區(qū)塊時(shí)間,時(shí)間是unix的絕對(duì)時(shí)間戳（自1970-01-01以來的秒數(shù)）
注意
獲得時(shí)間改變了區(qū)塊里的內(nèi)容野崇，因此該過程需要gas
pragma solidity ^0.4.22;
/*
+------------------------------------------------------------------------------+
| |
| XX XXXXX XXXXXX XXXXXXXXXXX XXXXXXXXXX |
| XX XX XXX XXX XXX X X X X |
| XX XX X X X XXXXXXXXXXX X X |
| XXXXXXXXX X X X X X |
| XX XX X X X X X |
| XX X X X XXXXXXXXXXX X X |
| |
| |
+------------------------------------------------------------------------------+
*/
contract date{
uint public date;
function getDate()public
{
date = now;
}
}
