前言new表达式,默认下把内存开辟到堆区。使用定位new表达式,可以在指定地址区域(栈区、堆区、静态区)构造对象,这好比是把内存开辟到指定区域。正文定位new表达式的常见形式
- new(address) type;
- new(address) type(initializers);
- new(address) type[size];
- new(address) type[size]{braced initializer list};
定位new表达式调用 void *operator new(size_t, void *); 分配内存。示例代码#include <iostream>
using namespace std;
char addr1[100];
int main()
{
cout << "******定位new表达式演示***by David***" << endl;
char addr2[100];
char *addr3 = new char[100];
cout << "addr1 = " << (void*)addr1 << endl;
cout << "addr2 = " << (void*)addr2 << endl;
cout << "addr3 = " << (void*)addr3 << endl;
int *p = nullptr;
//把内存分配到静态区
p = new(addr1)int;
*p = 1;
cout << (void*)p << " " << *p << endl;
//把内存分配到栈区
p = new(addr2)int;
*p = 2;
cout << (void*)p << " " << *p << endl;
//把内存分配到堆区
p = new(addr3)int;
*p = 3;
cout << (void*)p << " " << *p << endl;
cin.get();
return 0;
}运行------------------------------分割线------------------------------
C++ Primer Plus 第6版 中文版 清晰有书签PDF+源代码 http://www.linuxidc.com/Linux/2014-05/101227.htm读C++ Primer 之构造函数陷阱 http://www.linuxidc.com/Linux/2011-08/40176.htm读C++ Primer 之智能指针 http://www.linuxidc.com/Linux/2011-08/40177.htm读C++ Primer 之句柄类 http://www.linuxidc.com/Linux/2011-08/40175.htm
将C语言梳理一下,分布在以下10个章节中:- Linux-C成长之路(一):Linux下C编程概要 http://www.linuxidc.com/Linux/2014-05/101242.htm
- Linux-C成长之路(二):基本数据类型 http://www.linuxidc.com/Linux/2014-05/101242p2.htm
- Linux-C成长之路(三):基本IO函数操作 http://www.linuxidc.com/Linux/2014-05/101242p3.htm
- Linux-C成长之路(四):运算符 http://www.linuxidc.com/Linux/2014-05/101242p4.htm
- Linux-C成长之路(五):控制流 http://www.linuxidc.com/Linux/2014-05/101242p5.htm
- Linux-C成长之路(六):函数要义 http://www.linuxidc.com/Linux/2014-05/101242p6.htm
- Linux-C成长之路(七):数组与指针 http://www.linuxidc.com/Linux/2014-05/101242p7.htm
- Linux-C成长之路(八):存储类,动态内存 http://www.linuxidc.com/Linux/2014-05/101242p8.htm
- Linux-C成长之路(九):复合数据类型 http://www.linuxidc.com/Linux/2014-05/101242p9.htm
- Linux-C成长之路(十):其他高级议题
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