c++ new delete

分配基础类型

//c语言
int *p = (int *)malloc(sizeof(int)); 
free(p);
//c++,先初始化,再赋值
int *p2 = new int; //相当于上面的
*p2 = 1;
delete p2;
//c++,初始化,并赋值
int *p3 = new int(1);
delete p3;

分配数组

//c
int *p = (int *)malloc(10*sizeof(int));  //int a[10];
p[0] = 1;
free(p);
//c++
int *p2 = new int[10] ;//int a[10];
p2[0] = 1;
p2[1] = 2;
delete [] p2;

分配对象

Test t1(1, 2);//直接创建对象,在临时区分配内存

Test *p = new Test(1, 2);//new + 类型  返回一个 内存首地址
cout<<p->getA()<<endl;
delete p;

getTestObj(&p);
delete p;


//new操作符也会自动的调用这个类的构造函数
//delete自动的调用这个类的析构函数
//可以通过new和delete来控制对象的生命周期