按整数键升序对 TDictionary 进行排序

Question

如何在 Delphi 2009 中按升序按 Integer 键对 TDictionary 进行排序？

Answer 1

The RTL TDictionaries are not sorted and cannot be sorted (other than by hash, which they are). You need to use another container if you wish to sort either the keys or the values. For example :

program Project1;

{$APPTYPE CONSOLE}

uses
  Generics.Collections, Generics.Defaults, SysUtils;

var
  LDict : TDictionary<integer, string>;
  i, j : integer;
  LArray : TArray<integer>;
begin
  LDict := TDictionary<integer, string>.Create;
  try
    // Generate some values
    Randomize;
    for i := 0 to 20 do begin
      j := Random(1000);
      LDict.AddOrSetValue(j, Format('The Value : %d', [j]));
    end;
    WriteLn('Disorder...');
    for i in LDict.Keys do
      WriteLn(LDict.Items[i]);
    // Sort
    LArray := LDict.Keys.ToArray;
    TArray.Sort<integer>(LArray);
    WriteLn('Order...');
    for i in LArray do
      WriteLn(LDict.Items[i]);
  finally
    LDict.Free;
  end;
  Readln;
end.