困惑,请问布局new和常规new的区别和用法.谢谢!

[taurusbbstech]

如题.谢谢!

[大爷想要时光机]

详情请见 c++ primer 4th P638

[大爷想要时光机]

析构函数只析构对象不释放空间，这样就可以重用已有的内存空间，并且避免发生错误

[liveforme]

[Quote=引用 6 楼 Supper_Jerry 的回复:]
必须手工析构
[/Quote]

[冷月清晖]

http://topic.csdn.net/t/20051005/19/4308391.html

[paidfighting]

placement，就是只调用了构造函数，没有申请内存

[hai040]

class c;
c* p = new c;//normal
char buf[bufsize];
c* p2 = new(buf) c;//placement
char* pbuf = buf + sizeof(c);
c* p3 = new(pbuf) c;//placement

delete p;
//delete p2;//wrong

[hai040]

好像还要手动调用析构函数

class c;
c* p = new c;//normal
char buf[bufsize];
c* p2 = new(buf) c;//placement
char* pbuf = buf + sizeof(c);
c* p3 = new(pbuf) c;//placement

delete p;
//delete p2;//wrong
p2->~c();
p30>~c();

[paidfighting]

顶，手动析构

[Supper_Jerry]

必须手工析构