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map::operator[] (STL/CLR)

Maps a key to its associated mapped value.

    mapped_type operator[](key_type key);

Parameters

  • key
    Key value to search for.

Remarks

The member functions endeavors to find an element with equivalent ordering to key. If it finds one, it returns the associated mapped value; otherwise, it inserts value_type(key, mapped_type()) and returns the associated (default) mapped value. You use it to look up a mapped value given its associated key, or to ensure that an entry exists for the key if none is found.

Example

// cliext_map_operator_sub.cpp 
// compile with: /clr 
#include <cliext/map> 
 
typedef cliext::map<wchar_t, int> Mymap; 
int main() 
    { 
    Mymap c1; 
    c1.insert(Mymap::make_value(L'a', 1)); 
    c1.insert(Mymap::make_value(L'b', 2)); 
    c1.insert(Mymap::make_value(L'c', 3)); 
 
// display contents " [a 1] [b 2] [c 3]" 
    for each (Mymap::value_type elem in c1) 
        System::Console::Write(" [{0} {1}]", elem->first, elem->second); 
    System::Console::WriteLine(); 
 
    System::Console::WriteLine("c1[{0}] = {1}", 
        L'A', c1[L'A']); 
    System::Console::WriteLine("c1[{0}] = {1}", 
        L'b', c1[L'b']); 
 
// redisplay altered contents 
    for each (Mymap::value_type elem in c1) 
        System::Console::Write(" [{0} {1}]", elem->first, elem->second); 
    System::Console::WriteLine(); 
 
// alter mapped values and redisplay 
    c1[L'A'] = 10; 
    c1[L'c'] = 13; 
    for each (Mymap::value_type elem in c1) 
        System::Console::Write(" [{0} {1}]", elem->first, elem->second); 
    System::Console::WriteLine(); 
    return (0); 
    } 
 
 [a 1] [b 2] [c 3]
c1[A] = 0
c1[b] = 2
 [A 0] [a 1] [b 2] [c 3]
 [A 10] [a 1] [b 2] [c 13]

Requirements

Header: <cliext/map>

Namespace: cliext

See Also

Concepts

map (STL/CLR)

map::find (STL/CLR)

map::insert (STL/CLR)