From db9adbb04ab34761a0358058143120c5b52a6c65 Mon Sep 17 00:00:00 2001
From: InFini <107821372+Yumistar@users.noreply.github.com>
Date: Wed, 16 Oct 2024 23:02:01 +0800
Subject: [PATCH] =?UTF-8?q?Update=20He=C3=A2=E2=82=AC=E2=80=B9len.md?=
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 "He\303\242\342\202\254\342\200\271len.md" | 44 ++++++++++++++++++++++
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diff --git "a/He\303\242\342\202\254\342\200\271len.md" "b/He\303\242\342\202\254\342\200\271len.md"
index 5b74c03c..d5fb0093 100644
--- "a/He\303\242\342\202\254\342\200\271len.md"
+++ "b/He\303\242\342\202\254\342\200\271len.md"
@@ -1,3 +1,4 @@
+
 ---
 timezone: Asia/Shanghai
 ---
@@ -15,6 +16,49 @@ timezone: Asia/Shanghai
 ## Notes
 
 <!-- Content_START -->
+### 2024.10.16
+   2. internal v.s. external
+```solidity
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.21;
+contract FunctionTypes{
+    uint256 public number = 5;
+// 默认function
+function add() external{
+    number = number + 1;
+}
+
+// pure: 纯纯牛马
+function addPure(uint256 _number) external pure returns(uint256 new_number){
+    new_number = _number + 1;
+}
+// internal: 内部函数
+function minus() internal {
+    number = number - 1;
+}
+
+// 合约内的函数可以调用内部函数
+function minusCall() external {
+    minus();
+}
+// 合约内的函数可以调用内部函数
+function minusCall() external {
+    minus();
+}
+// payable: 递钱，能给合约支付eth的函数
+function minusPayable() external payable returns(uint256 balance) {
+    minus();    
+    balance = address(this).balance;
+}
+}
+```
+我們定義一個函數internal，minus()每次調用使得變數減number1 。internalexternalminusCall()minus()
+
+3.應付
+定義一個external payable函數minusPayable()，引用的調用，並且返回合約minus()裡的ETH餘額（this關鍵字可以讓我們引用合約位址）。minusPayable()
+
+
+
 ### 2024.10.12
 實作
 ```solidity