31.md

第31讲(數據儲存位置)

事件

/**
 * Transfer時呼叫
 */
event Transfer(address indexed from, address indexed to, uint256 value);

/**
 * Approve時呼叫
 */
event Approval(address indexed owner, address indexed spender, uint256 value);

函數

1. totalSupply() => 總供給量
2. balanceOf(account) => 帳戶餘額
3. transfer(to, amount) => 從自己到轉代幣到to
4. allowance(owner, spender) => 返回owner授權給spender的額度
5. approve(spender, amount) => 自己授權代幣給spender
6. transferFrom(from, to, amount) => 透過授權，從from帳戶轉向to代幣。同時allowance的額度會被扣除。
7. mint(amount) => 鑄造代幣
8. burn(amount) => 銷毀代幣