System.Generics.Dictionary (en)

Represents a generic collection of key/value pairs.

 IDictionary<TKey,TValue> = interface

 TDictionary<TKey,TValue> = class(TInterfacedObject, IDictionary<TKey,TValue>)

Examples

The following code example creates an empty Dictionary<TKey,TValue> of strings, with string keys, and accesses it through the IDictionary<TKey,TValue> interface.

procedure UseDictionary;
var
  dictionary: IDictionary<string, string>;
  item: TPair<string, string>;
begin
  Writeln('Print all environment variables...');

  dictionary := System.Generics.Dictionary.TDictionary<string, string>.Create;
  dictionary.Add('Key1', 'Value1');
  dictionary.Add('Key2', 'Value2');

  Writeln('Dictionary contains ' + dictionary.Count.ToString + ' elements');

  if not dictionary.ContainsKey('Key1') then
    raise Exception.Create('Dictionary not contain key1 item');


  Writeln('Dictionary items:');
  for item in dictionary do
    Writeln(item.Key + ' = ' + item.Value);
end;