hash_multimap::get_allocator
注意事項 |
---|
這個 API 已經過時。這個選項是 unordered_multimap Class。 |
傳回用來配置器物件的複製建構 hash_multimap。
Allocator get_allocator( ) const;
傳回值
hash_multimap 使用的配置器。
備註
hash_multimap 類別的配置器指定類別如何處理儲存區。 預設配置器提供 STL 容器類別的大部分程式的需求就已足夠。 撰寫和使用的配置器類別是進階 C++ 主題。
在 Visual C++ .NET Pocket PC, <hash_map> 和 <hash_set> 標頭檔 (Header File) 的成員不在 std 命名空間,,而是移至 stdext 命名空間。 如需詳細資訊,請參閱 stdext 命名空間。
範例
// hash_multimap_get_allocator.cpp
// compile with: /EHsc
#include <hash_map>
#include <iostream>
int main( )
{
using namespace std;
using namespace stdext;
hash_multimap <int, int>::allocator_type hm1_Alloc;
hash_multimap <int, int>::allocator_type hm2_Alloc;
hash_multimap <int, double>::allocator_type hm3_Alloc;
hash_multimap <int, int>::allocator_type hm4_Alloc;
// The following lines declare objects
// that use the default allocator.
hash_multimap <int, int> hm1;
hash_multimap <int, int> hm2;
hash_multimap <int, double> hm3;
hm1_Alloc = hm1.get_allocator( );
hm2_Alloc = hm2.get_allocator( );
hm3_Alloc = hm3.get_allocator( );
cout << "The number of integers that can be allocated"
<< endl << " before free memory is exhausted: "
<< hm2.max_size( ) << "." << endl;
cout << "The number of doubles that can be allocated"
<< endl << " before free memory is exhausted: "
<< hm3.max_size( ) << "." << endl;
// The following line creates a hash_multimap hm4
// with the allocator of hash_multimap hm1.
hash_multimap <int, int> hm4( less<int>( ), hm1_Alloc );
hm4_Alloc = hm4.get_allocator( );
// Two allocators are interchangeable if
// storage allocated from each can be
// deallocated by the other
if( hm1_Alloc == hm4_Alloc )
{
cout << "The allocators are interchangeable."
<< endl;
}
else
{
cout << "The allocators are not interchangeable."
<< endl;
}
}
範例輸出
下列輸出是 x86。
The number of integers that can be allocated
before free memory is exhausted: 536870911.
The number of doubles that can be allocated
before free memory is exhausted: 268435455.
The allocators are interchangeable.
需求
標題: <hash_map>
命名空間: stdext