델피치 안의 교체.

var

  S: string;

  i: integer;

begin

  for i := 0 to MyStrings.Count-1 do

  begin

    S := MyStrings[i];

    writeln(S);

  end;

end;

var

  S: string;

begin

  for S in MyStrings do

    writeln(S);

end;

         ，             ：

1.       class , interface    record       

2.   class ,interface   record        GetEnumerator  ，            

3.        class , interface    record      。

4.         MoveNext(): boolean; Current:      。

5.MoveNext                   False，    True

6.                -1，   moveNext           。

   ：

type

  {     }

  TRecordEnumerator = record

  private

    FArray: TBytes;

    FIndex: Integer;



    function GetCurrent: Byte;

  public

    function MoveNext(): Boolean;

    property Current: Byte read GetCurrent;

  end;



  {         }

  TRecordCollection = record

  private

    FArray: TBytes;

  public

    function GetEnumerator(): TRecordEnumerator;

  end;



{ TRecordCollection }



function TRecordCollection.GetEnumerator: TRecordEnumerator;

begin

  Result.FArray := FArray;

  Result.FIndex := -1;

end;



{ TRecordEnumerator }



function TRecordEnumerator.GetCurrent: Byte;

begin

  Result := FArray[FIndex];

end;



function TRecordEnumerator.MoveNext: Boolean;

begin

  Inc(FIndex);



  if FIndex >= Length(FArray) then

    Exit(false);



  Exit(true);

end;



var

  LColl: TRecordCollection;

  B: Byte;



begin

  LColl.FArray := TBytes.Create(1, 2, 3, 4, 5, 6);



  for B in LColl do

    WriteLn(B);



  ReadLn;

end.