1.状态变量

pragma solidity >=0.4.0 <0.6.0;

contract SimpleStorage {
     uint storedData; //整型变量
     // ......
     }

2.函数

pragma solidity >=0.4.0 <0.6.0;

contract SimpleAuction {
     function bid () public payable{
     // ......
     //同时函数还包括输入参数和返回类型说明
     }
     }

3.函数修饰器

pragma solidity >=0.4.22 <0.6.0;
contract Purchase{
    address public seller;
    //定义函数修饰器，该修饰器可以用于函数条件限制
    modifier onlySeller() {
        require{
            masg.sender == seller,
            "Only seller can this."
        };
         _;
    }
}

4.事件

pragma solidity >=0.4.0 <0.6.0;

contract SimpleAuction {
    event HighestBidIncreased (address bidder, uint amount) ;//事件原型
    
     function bid () public payable{
         // ......
         emit HighestBidIncreased (msg.sender, msg.value) ; //触发事件
     }
     }

5.结构体

pragma solidity >=0.4.0 <0.6.0;

contract Ballot{
    struct Voter{  //通过struct关键字，定义一个合约内的结构
        
        uint weight; //结构体内定义的成员变量
        bool voted;
        address delegate;
        uint vote;
        }
    }

6.枚举类型

pragma solidity >=0.4.0 <0.6.0;

contract Purchase{
    enum State { Created, Locked, Inactive } //从0开始，定义枚举变量
    }