[長知識] C++ x this this this

這裡是說明this怎麼使用

以下面這個範例來說

如果y是大於0的話，就把y丟給this->y，如果不是大於0就把1丟給this->y

this->y=(y>0)?y:1;

#include <iostream>
#include <cstdlib>

using namespace std;
//物件導向  

//這邊一開始宣告Room類別 
class Room{
 //分別有 public, protect, private 
 public:
  Room(){
   //建構式: 特殊函示成員，在類別物件建立時執行，
   //白話講，就是給他預設值啦~ 
   cout<<"Constructor called!!"<x=x;
   this->y=y;
   this->z=z;
   set(x, y, z);
  }     
  int RoomSize(){
   return x*y*z;
  }
  void print(){
   cout<<"x:"<x=(x>0)?x:1;
   this->y=(y>0)?y:1;
   this->z=(z>0)?z:1;
  }
private:
 int x, y, z;   
}; 

int main(){
  Room room1(3, 4, 5), room2(6, 7, 8);
  Room* ptrRoom;
 
 ptrRoom = (room1.RoomSize()> room2.RoomSize())?&room1:&room2;
   ptrRoom->print(); 
  system("pause");
 return 0;
}

輸出結果: