FieldByNameのような関数を自作したい (ID:28801)

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あきらめちゃいましたか・・・

FieldByName は オブジェクト FieldByName2 はレコードを使用した場合です

unit MyTable;

interface

uses
  SysUtils, Classes;

type

TMyField = class(TComponent)
  private
    FAsString : String;
  published
    property asString :String read fAsString;
  end;

TMyField2 = record
    asString : String;
  end;

TMyTable = class(TComponent)
  private
    FMyField  : TMyField;
    FMyField2 : TMyField2;
    FIndex  : Integer;
    FName : array[0..255] of string;
    FData : array[0..255,0..999] of string;
  protected
    procedure SetNames(Index:Integer;Value:String);
    function  GetNames(Index:Integer):String;
    procedure SetDatas(Index1,Index2:Integer;Value:String);
    function  GetDatas(Index1,Index2:Integer):String;
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    function FieldByName(AName:String):TMyField;
    function FieldByName2(AName:String):TMyField2;
    property Names [Index:Integer] : String read GetNames write SetNames;
    property Datas [Index1,Index2:Integer] : String read GetDatas write SetDatas;
    procedure First;
    procedure Next;
  published
    property Index : Integer read FIndex write FIndex;
  end;

procedure Register;

implementation

procedure TMyTable.SetNames(Index: Integer; Value: string);
begin
    FName[Index] := Value;
end;

function TMyTable.GetNames(Index: Integer):String;
begin
    Result := FName[Index];
end;

procedure TMyTable.SetDatas(Index1,Index2: Integer; Value: string);
begin
    FData[Index1,Index2] := Value;
end;

function TMyTable.GetDatas(Index1,Index2: Integer):String;
begin
    Result := FData[Index1,Index2];
end;

procedure TMyTable.First;
begin
    FIndex := 0;
end;

procedure TMyTable.Next;
begin
    Inc(FIndex);
end;

function TMyTable.FieldByName(AName:String):TMyField;
var
    I,J : Integer;
begin
    //ANameに一致するFNameを探す
    J := -1;
    for I:=0 to High(FName) -1 do
    begin
      if FName[I] = AName then J := I;
    end;
    if J <> -1 then
    begin
      //見付かったら
      FMyField.FAsString := Datas[J,Index];
    end
    else
    begin
      //見付からなければ
      FMyField.FAsString := '';
    end;
    Result := FMyField;
end;

function TMyTable.FieldByName2(AName:String):TMyField2;
var
    I,J : Integer;
begin
    //ANameに一致するFNameを探す
    J := -1;
    for I:=0 to High(FName) -1 do
    begin
      if FName[I] = AName then J := I;
    end;
    if J <> -1 then
    begin
      //見付かったら
      FMyField2.AsString := Datas[J,Index];
    end
    else
    begin
      //見付からなければ
      FMyField2.AsString := '';
    end;
    Result := FMyField2;
end;

constructor TMyTable.Create(AOwner: TComponent);
begin
    inherited Create(AOwner);

FMyField := TMyField.Create(Self);
end;

destructor TMyTable.Destroy;
begin
    FMyField.Free;
    inherited Destroy;
end;

procedure Register;
begin
  RegisterComponents('KHE00221', [TMyTable]);
end;

end.

-------------------------------------------------------------------

MyTable を使用した例

------------------------------------------------------------------

procedure TForm1.Button1Click(Sender: TObject);
var
    I,J : Integer;
begin
    //データ初期化
    for I:=0 to 10 do
    begin
      for J:=0 to 99 do
      begin
        MyTable1.Names[I] := 'Name'+IntToStr(I);
        MyTable1.Datas[I,J] := 'Data'+IntToStr(I)+'/'+IntToStr(J);
      end;
    end;
    //表示
    Memo1.Lines.Add(MyTable1.FieldByName('Name1').asString);
    Memo1.Lines.Add(MyTable1.FieldByName('Name20').asString);
    MyTable1.Next;
    Memo1.Lines.Add(MyTable1.FieldByName2('Name2').asString);
    Memo1.Lines.Add(MyTable1.FieldByName2('Name30').asString);
end;

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