來到第五天了！
今天就讓我們在合約裡儲存資料吧！
通過這個簡單的範例來學習怎麼宣告 State Variables 以及 constructor, getter, and setter 的應用。

Contract Source Code:

pragma solidity ^0.4.25;

contract StateVariables {
	string name;
	address owner;
	constructor() public {
	    /* Initailize state variables. */
		name = "unknown";
		owner = msg.sender;
	}

	function setName(string _name) public returns (string) {
	    /* Only owner has the permission to modify its name. */
		if (msg.sender == owner) {
			name = _name;
		} else {
			revert("Permission denied.");
		}
		return name;
	}

	function getName() public view returns (string) {
		return name;
	}
}

本日影片:
https://youtu.be/0yFl7KbDLlU

Smart Contract 實戰教學播放清單:
https://www.youtube.com/playlist?list=PLHmOMPRfmOxSJcrlwyandWYiuP9ZAMYoF