类构造和析构执行次数

最新推荐文章于 2023-06-24 09:36:39 发布

转载最新推荐文章于 2023-06-24 09:36:39 发布 · 197 阅读

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原文链接：http://www.cnblogs.com/fickleness/p/3342684.html

本文详细解析了C++中类的构造函数和析构函数的使用，通过实例展示了如何在创建对象时调用构造函数，在销毁对象时调用析构函数，以及构造函数和析构函数的执行次数。

#include <iostream>
using namespace std;

class A
{
 public:
  int age;
  static int count;
 public:
  A(int i=2) : age(i)
  {
   this->age = i;
   cout << "gou zao "<<A::count << " age="<<age <<endl;
   A::count++;  
  }
  ~A()
  {
   cout << "xi gou "<< endl;
  }  
};
int A::count = 0;
int main(int argc, const char *argv[])
{
 A* arr = new A[10];    //产生10个A类对象 
 delete []arr;

 A *p = new A(25); 
 delete p;

 A *p2 = new A;
 delete p2;

 return 0;
}

gou zao 0 age=2
gou zao 1 age=2
gou zao 2 age=2
gou zao 3 age=2
gou zao 4 age=2
gou zao 5 age=2
gou zao 6 age=2
gou zao 7 age=2
gou zao 8 age=2
gou zao 9 age=2
xi gou 
xi gou 
xi gou 
xi gou 
xi gou 
xi gou 
xi gou 
xi gou 
xi gou 
xi gou 
gou zao 10 age=25
xi gou 
gou zao 11 age=2
xi gou 




question
A *pa=new pa[10];
delete pa;
构造函数和析构函数分别执行了几次


answer：
#include <iostream>

using namespace std;

class A
{
 public:
  int age;
  static int count;
 public:
  A(int i=2) : age(i)
  {
   this->age = i;
   cout << "gou zao "<<A::count << " age="<<age <<endl;
   A::count++;  
  }
  ~A()
  {
   cout << "xi gou "<< endl;
  }  
};
int A::count = 0;
int main(int argc, const char *argv[])
{
 A* arr = new A[10];    //产生10个A类对象 
 delete arr;

 A *p = new A(25);  //有参构造 
 delete p;

 A *p2 = new A;//default constructor
 delete p2;

 return 0;
}

執行期間發生錯誤（RE） time: 0 memory: 3432 signal:6

gou zao 0 age=2
gou zao 1 age=2
gou zao 2 age=2
gou zao 3 age=2
gou zao 4 age=2
gou zao 5 age=2
gou zao 6 age=2
gou zao 7 age=2
gou zao 8 age=2
gou zao 9 age=2
xi gou 

10次和1次

转载于:https://www.cnblogs.com/fickleness/p/3342684.html