cxk228922.md

timezone
Asia/Taipei

---

Robin

1. 自我介绍
   大家好我是Robin(cxk228922)，一名正在台灣就讀高二的學生，對資訊安全頗有興趣
   之前都是往計算機本身漏洞探究，想慢慢跨進到網路相關的內容。
2. 你认为你会完成本次残酷学习吗？
   我會盡我所能完成一切

Notes

這邊先和助教說聲抱歉，由於我最近課業繁忙，並且對網路、區塊鏈並沒有基礎，每天能學習的內容有限><。以及我想趁此機會練習英文，文法可能有許多不妥處，可能有點難以閱讀。

2024.09.23

101

1. Remix IDE

• File Extension of Solidity : .sol
• Ctrl + S -> Compile
• Deploy -> Simulate Ethereum chain -> run smart contracts

2. Basic

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.21;
contract HelloWeb3{
    string public _string = "Hello Web3!";
}

• // SPDX-License-Identifier: MIT -> Denotes license identifier (MIT for example)
• pragma solidity ^0.8.21; -> Only allow compiler version 0.8.21 ~ 0.9.0(0.8.21 for example)
• contract HelloWeb3 -> Similar as class in other programming language (HelloWeb3 for example). also,we call it "合約"
• string public _string = "Hello Web3!"; -> Declared Variables
• string : Value type

Type	Explain	Example
int	integer	3 , 300 , -123
uint	unsigned integer(include 0)	3 , 300
uint	k-bit unsigned integer	uint8 , uint64
bool	boolean	true , false
address	address(e.g. ETH account)	0x1234556
enum	enumeration	{Mon=1,Tue,Wed}

• public : visibility

Type	Outside Contract	In Contract	Inheritance Contract
public	✅	✅	✅
private	❌	✅	❌
external (function)	✅	✅use this.func()	✅use this.func()
internal	❌	✅	✅

• _string : Value name,Define by your self
• "Hello Web3!" : Value

---

function <functionName>(<Type> <ParameterName>) <visibility> <modifier> returns (<Type>) 

<Type> <parameter1> : Input parameter,e.g. int a
     Also,you can input more than 1 parameter

<modifier> :

Value	Explain
pure	cannot read nor write
view	can read but cannot write
(NULL)	can both read and write
payable	can receive ETH