c++ cli - Accessing a dictionary key by its index -

it's easy question how access value of dictionary key in specific row. let's dict { 1,13; 3,14; 5,17 } second key 3.

how value? tried dict->key[2] gave error , can't find reference

update: gives me need maybe there faster way.

 dictionary<double, double>::keycollection^ keycoll = dict->keys;   double first;  double last;    int counter=0;   int dictionarycount = dict->count; each( double s in keycoll ) { if(counter==0){     first=s; } if(dictionarycount == counter+1){     last=s; } //dict[first] first key //dict[last] last key 

the dictionary<> class has indexer, use applying [] operator directly object reference. named item in msdn library articles. indexer dictionary takes key , returns value key. sample code:

auto dict = gcnew dictionary<int, double>(); dict->add(1, 13); dict->add(3, 14); dict->add(5, 17); auto value = dict[3]; 

you use trygetvalue() method instead if not sure if key present.

the dictionary dict<double,double>

do beware using double key very troublesome. comparing floating point values equality filled surprises, none of them ones. must use dictionary(iequalitycomparer<>) constructor , pass own comparer have hope of surviving this. ask question if necessary.