运营商删除(operator delete)
描述 (Description)
它释放存储空间。
声明 (Declaration)
以下是operator new []的声明。
void operator delete (void* ptr) throw(); (ordinary delete)
void operator delete (void* ptr, const std::nothrow_t& nothrow_constant) throw(); (nothrow delete)
void operator delete (void* ptr, void* voidptr2) throw(); (placement delete)
C++11
void operator delete (void* ptr) noexcept; (ordinary delete)
void operator delete (void* ptr, const std::nothrow_t& nothrow_constant) noexcept; (nothrow delete)
void operator delete (void* ptr, void* voidptr2) noexcept; (placement delete)
C++14
void operator delete (void* ptr) noexcept; (ordinary delete)
void operator delete (void* ptr, const std::nothrow_t& nothrow_constant) noexcept; (nothrow delete)
void operator delete (void* ptr, void* voidptr2) noexcept; (placement delete)
void operator delete (void* ptr, std::size_t size) noexcept; (ordinary delete with size)
void operator delete (void* ptr, std::size_t size,
const std::nothrow_t& nothrow_constant) noexcept; (ordinary delete with size)
参数 (Parameters)
size - 它包含所请求内存块的大小（以字节为单位）。
nothrow_value - 它包含常量nothrow_value 。
ptr - 它是指向已经分配的适当大小的内存块的指针。
voidptr2 - 它是一个void指针。
返回值 (Return Value)
没有
异常 (Exceptions)
No-throw guarantee - 此函数永远不会抛出异常。
数据竞争 (Data races)
它修改返回值引用的存储。
例子 (Example)
在下面的例子解释了新的运算符。
#include <iostream>
struct MyClass {
MyClass() {std::cout <<"It is a MyClass() constructed\n";}
~MyClass() {std::cout <<"It is a MyClass() destroyed\n";}
};
int main () {
MyClass * pt = new (std::nothrow) MyClass;
delete pt;
return 0;
}
让我们编译并运行上面的程序，这将产生以下结果 -
It is a MyClass() constructed
It is a MyClass() destroyed
