From b8472807aa93adb0bdedd24888840673d2135407 Mon Sep 17 00:00:00 2001
From: jiulinxiri <jiulinxiri@hotmail.com>
Date: Fri, 7 Jan 2022 11:10:38 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BF=AE=E6=94=B9=20README=20=E6=96=87?=
 =?UTF-8?q?=E4=BB=B6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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---
 08 类.playground/Resources/README.md | 45 +++++++++++++--------------
 1 file changed, 21 insertions(+), 24 deletions(-)

diff --git a/08 类.playground/Resources/README.md b/08 类.playground/Resources/README.md
index 56c4d2a..87beb32 100644
--- a/08 类.playground/Resources/README.md	
+++ b/08 类.playground/Resources/README.md	
@@ -21,12 +21,12 @@ func test() {
 
 test()方法在内存中的存储结构
 
-<img src="https://vip1.loli.io/2022/01/06/5nON1A42PkVFijr.png" alt="jiulinxiri_20220106223910.png" style="zoom: 50%;" />
+<img src="https://vip1.loli.io/2022/01/06/5nON1A42PkVFijr.png" alt="jiulinxiri_20220106223910.png" style="zoom: 33%;" />
 
 * point结构体是值类型，在内存中存储的是值
 * size类是引用类型，在内存中存储的是Size对象的内存地址
 
-<img src="https://vip1.loli.io/2022/01/06/TRshqXCfrilFnQu.png" alt="jiulinxiri_20220106224431.png" style="zoom:50%;" />
+<img src="https://vip1.loli.io/2022/01/06/TRshqXCfrilFnQu.png" alt="jiulinxiri_20220106224431.png" style="zoom: 33%;" />
 
 * 前边16个字节存储的是指向类型信息以及引用计数
 * 后边的16个字节存储的是成员变量
@@ -50,7 +50,7 @@ var p2 = p1
 
 栈空间的存储结构如下所示
 
-<img src="https://vip2.loli.io/2022/01/07/yqFHwWRzdZXLnOa.png" alt="jiulinxiri_20220107093427" style="zoom:50%;" />
+<img src="https://vip2.loli.io/2022/01/07/yqFHwWRzdZXLnOa.png" alt="jiulinxiri_20220107093427" style="zoom: 33%;" />
 
 > p1和p2成员变量之间的赋值操作没有任何影响
 
@@ -94,7 +94,7 @@ func test() {
 
 内存中的存储结构如下图所示
 
-<img src="https://vip2.loli.io/2022/01/07/WuKTbg8Zn5NvFip.png" alt="jiulinxiri_20220107102828" style="zoom:50%;" />
+<img src="https://vip2.loli.io/2022/01/07/WuKTbg8Zn5NvFip.png" alt="jiulinxiri_20220107102828" style="zoom: 33%;" />
 
 
 
@@ -115,31 +115,28 @@ s1 = Size(width: 11, height: 22)
 
 内存中的结构如下图所示
 
-<img src="https://vip1.loli.io/2022/01/07/CDTPEudHcjVbnLM.png" alt="jiulinxiri_20220107104836" style="zoom:50%;" />
+<img src="https://vip1.loli.io/2022/01/07/CDTPEudHcjVbnLM.png" alt="jiulinxiri_20220107104836" style="zoom: 33%;" />
 
 
 
+#### 对象堆空间申请过程
 
+在Swift中，创建类的实例对象，要向堆空间申请内存，大概流程如下
 
+* Class.__allocating_init()_
+* libswiftCore.dylib：_swift_allocObject_
+* libswiftCore.dylib：swift_slowAlloc
+* libsystem_malloc.dylib：malloc
 
+**在Mac、iOS中的malloc函数分配的内存大小总是16的倍数**
+通过 `class_getInstanceSize` 可以得知：类的对象至少需要占用多少内存
 
+```swift
+class Point	{  var x = 11
+var test = true
+var y = 22
+}
+var p = Point()  class_getInstanceSize(type(of: p)) // 40  
+class_getInstanceSize(Point.self) // 40
+```
 
-
-
-
-
-
-
-
-
-
-
-
-> 对象的堆空间申请过程
->
->  在Swift中，创建类的实例对象，要向堆空间申请内存，大概流程如下
->
-> 1. Class.__allocating_init()_
-> 2. libswiftCore.dylib：_swift_allocObject_
-> 3. libswiftCore.dylib：swift_slowAlloc
-> 4. libsystem_malloc.dylib：malloc