如何为TDictionary创建一个敏感的TEqualityComparer案例？

我有一个使用TDictionary的案例:

var D: TDictionary;
begin
  D := TDictionary.Create(TCustomEqualityComparer.Create());
  try
    D.Add('One', 1);
    D.Add('Two', 2);
    D.Add('Three', 3);

    showmessage(inttostr(D.Items['One']));
    showmessage(inttostr(D.Items['TWO']));
  finally
    D.Free;
  end;
end;

从Generics Defaults TEqualityComparer(Delphi)复制类TCustomEqualityComparer,对GetHashCode方法进行微小修改:

TCustomEqualityComparer = class(TEqualityComparer)
public
  function Equals(const Left, Right: string): Boolean; override;
  function GetHashCode(const Value: string): Integer; override;
end;

function TCustomEqualityComparer.Equals(const Left, Right: string): Boolean;
begin
  Result := SameText(Left, Right);
end;

function TCustomEqualityComparer.GetHashCode(const Value: string): Integer;
begin
  Result := BobJenkinsHash(Value[1], Length(Value) * SizeOf(Value[1]), 0);
end;

我希望TCustomEqualityComparer能够对键值执行不区分大小写的匹配.例如:

D.Items['TWO']

但是,我收到"找不到项目"的例外情况.我使用的是Delphi 2010版本14.0.3513.24210.

有谁知道我的代码有什么问题？

uses System.Generics.Collections, System.Generics.Defaults;

var
  D: TDictionary;
begin
  D := TDictionary.Create(TIStringComparer.Ordinal); // ‹- this is the trick
  try
    D.Add('One', 1);
    .
    .
  finally
    D.Free;
  end;
end;