hash_multimap::find

说明
此 API 已过时。另一种方法是 unordered_multimap Class。

返回解决的迭代器一个元素的第一个位置在具有键等效于指定的键的 hash_multimap 的。

iterator find(
   const Key& _Key
);
const_iterator find(
   const Key& _Key
) const;

参数

• _Key
  一个元素的排序关键字将匹配的键从要搜索的 hash_multimap 的。

返回值

解决一个元素第一个位置与指定的键的迭代器或成功最后一个元素的位置。hash_multimap，如果与未作为项中。

备注

成员函数返回解决在 hash_multimap 的元素排序关键字是 equivalent 给参数键在二进制谓词该应用可比性关系生成基于的排序小于零的迭代器。

如果 查找 的返回值赋给 const_iterator，不能修改 hash_multimap 对象。如果 查找 的返回值赋给 迭代器，可以修改 hash_multimap 对象。

在 Visual C++ .NET 2003 中，<hash_map> 和 <hash_set> 标头文件的成员中不再标准，命名空间，而是将 stdext 命名空间。有关更多信息，请参见 stdext 命名空间。

示例

// hash_multimap_find.cpp
// compile with: /EHsc
#include <iostream>
#include <hash_map>

int main()
{
    using namespace std;
    using namespace stdext;
    hash_multimap<int, int> hm1;
    hash_multimap<int, int> :: const_iterator hm1_AcIter, hm1_RcIter;
    typedef pair<int, int> Int_Pair;

    hm1.insert(Int_Pair(1, 10));
    hm1.insert(Int_Pair(2, 20));
    hm1.insert(Int_Pair(3, 20));
    hm1.insert(Int_Pair(3, 30));

    hm1_RcIter = hm1.find(2);
    cout << "The element of hash_multimap hm1 with a key of 2 is: "
          << hm1_RcIter -> second << "." << endl;

    hm1_RcIter = hm1.find(3);
    cout << "The first element of hash_multimap hm1 with a key of 3 is: "
          << hm1_RcIter -> second << "." << endl;

    // If no match is found for the key, end() is returned
    hm1_RcIter = hm1.find(4);

    if (hm1_RcIter == hm1.end())
        cout << "The hash_multimap hm1 doesn't have an element "
             << "with a key of 4." << endl;
    else
        cout << "The element of hash_multimap hm1 with a key of 4 is: "
             << hm1_RcIter -> second << "." << endl;

    // The element at a specific ___location in the hash_multimap can be
    // found using a dereferenced iterator addressing the ___location
    hm1_AcIter = hm1.end();
    hm1_AcIter--;
    hm1_RcIter = hm1.find(hm1_AcIter -> first);
    cout << "The first element of hm1 with a key matching"
         << endl << "that of the last element is: "
         << hm1_RcIter -> second << "." << endl;

    // Note that the first element with a key equal to
    // the key of the last element is not the last element
    if (hm1_RcIter == --hm1.end())
        cout << "This is the last element of hash_multimap hm1."
             << endl;
    else
        cout << "This is not the last element of hash_multimap hm1."
             << endl;
}

要求

标头： <hash_map>

命名空间： stdext

请参见

参考

hash_multimap Class

标准模板库