unit1.pas

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unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls, DB, Grids, DBGrids, DBTables;

type
  TForm1 = class(TForm)
    Memo1: TMemo;
    RadioGroup1: TRadioGroup;
    Button1: TButton;
    Button2: TButton;
    Table1: TTable;
    DBGrid1: TDBGrid;
    DataSource1: TDataSource;
    Table1Notes: TMemoField;
    Table1SpeciesNo: TFloatField;
    Table1Category: TStringField;
    Table1Common_Name: TStringField;
    Table1SpeciesName: TStringField;
    Table1Lengthcm: TFloatField;
    Table1Length_In: TFloatField;
    Table1Graphic: TGraphicField;
    procedure Button1Click(Sender: TObject);
    procedure CreateTStream(selectedIndex:integer);
    procedure Button2Click(Sender: TObject);
  private
    FStream:TStream;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
procedure TForm1.createTStream(selectedIndex:integer);
begin
  case selectedIndex of
    //将“计算机英语.txt“（文件中）读入到流中
    0: FStream:=TFileStream.Create('计算机英语.txt',fmOpenRead);
    //RadioGroup1显示的文字项（内存中）读入到流中
    1: begin
         FStream:=TMemoryStream.Create;
         RadioGroup1.Items.SaveToStream(FStream);
         FStream.Position := 0;
       end;
    //数据库备注字段内容（Blob字段中）读入到流中
    2: FStream:=TBlobStream.Create(Table1Notes,bmRead);
  end;
end;



procedure TForm1.Button1Click(Sender: TObject);
begin
  createTStream(RadioGroup1.ItemIndex);
  try
    Memo1.Lines.LoadFromStream(FStream);
  finally
    FStream.Free;
  end;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  close;
end;

end.