unordered_map::key_type

發行項
06/09/2015

排序索引鍵的類型。

typedef Key key_type;

備註

這個型別是樣板參數 Key的同義字。

範例

// std_tr1__unordered_map__unordered_map_key_type.cpp 
// compile with: /EHsc 
#include <unordered_map> 
#include <iostream> 
 
typedef std::unordered_map<char, int> Mymap; 
int main() 
    { 
    Mymap c1; 
 
    c1.insert(Mymap::value_type('a', 1)); 
    c1.insert(Mymap::value_type('b', 2)); 
    c1.insert(Mymap::value_type('c', 3)); 
 
// display contents " [c 3] [b 2] [a 1]" 
    for (Mymap::const_iterator it = c1.begin(); 
        it != c1.end(); ++it) 
        std::cout << " [" << it->first << ", " << it->second << "]"; 
    std::cout << std::endl; 
 
// add a value and reinspect 
    Mymap::key_type key = 'd'; 
    Mymap::mapped_type mapped = 4; 
    Mymap::value_type val = Mymap::value_type(key, mapped); 
    c1.insert(val); 
 
    for (Mymap::const_iterator it = c1.begin(); 
        it != c1.end(); ++it) 
        std::cout << " [" << it->first << ", " << it->second << "]"; 
    std::cout << std::endl; 
 
    return (0); 
    }