C/C++笔记：指针和结构体

1. 通过指针访问自定义数据类型

typedef struct Role {
	int HP;
	int MP;
}*PRole;

int main()
{
	Role user;
	PRole puser = &user;

	puser->HP = 50;
	puser->MP = 50;

	user.HP = 50;
	user.MP = 50;
}

• *PRole 定义为结构体Role的指针，使其可通过指针访问结构体。
• 指针用->访问；
• .对应的是实体；

反汇编:

	Role user;
	PRole puser = &user;
007C17D2  lea         eax,[user]                 // []内容代代表地址， eax = [user]
007C17D5  mov         dword ptr [puser],eax    // [puser] = [user]

	puser->HP = 50;
007C17D8  mov         eax,dword ptr [puser]  
007C17DB  mov         dword ptr [eax],32h  
	puser->MP = 50;
007C17E1  mov         eax,dword ptr [puser]  
007C17E4  mov         dword ptr [eax+4],32h   //偏移 4个字节

	user.HP = 50;
007C17EB  mov         dword ptr [user],32h  
	user.MP = 50;
007C17F2  mov         dword ptr [ebp-0Ch],32h