Delphi 2009 中 TStrings 與 TStream 的增強

　在 Delphi 2009 中,

　　TStrings 類(包括 TStringList 和包含 TStrings 屬性的所有組件, 譬如 Memo.lines 屬性、ListBox.Items 屬性)、

　　TStream 類系列(包括 TFileStream、TMemoryStream 等) 的存取方法, 譬如:

　　LoadFromFile、SaveToFile、LoadFromStream、SaveToStream, 都有了選擇 TEncoding 參數的重載.

　　本例效果圖:

　　代碼文件:unit Unit1;
interface
uses
　Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
　Dialogs, StdCtrls;
type
　TForm1 = class(TForm)
　　Memo1: TMemo;
　　Memo2: TMemo;
　　Button1: TButton;
　　Button2: TButton;
　　Button3: TButton;
　　Button4: TButton;
　　Button5: TButton;
　　Button6: TButton;
　　Button7: TButton;
　　Button8: TButton;
　　Button9: TButton;
　　procedure FormCreate(Sender: TObject);
　　procedure Button1Click(Sender: TObject);
　　procedure Button2Click(Sender: TObject);
　　procedure Button3Click(Sender: TObject);
　　procedure Button4Click(Sender: TObject);
　　procedure Button5Click(Sender: TObject);
　　procedure Button6Click(Sender: TObject);
　　procedure Button7Click(Sender: TObject);
　　procedure Button8Click(Sender: TObject);
　　procedure Button9Click(Sender: TObject);
　end;
var
　Form1: TForm1;
implementation
{$R *.dfm}
const
　FilePath = 'c:temptest.txt';
var
　str: string;
procedure TForm1.FormCreate(Sender: TObject);
begin
　Memo1.ReadOnly := True;
　str := Memo1.Text;
　Button1.Caption := 'TStrings 默認存取';
　Button2.Caption := 'TStrings ASCII 存取';
　Button3.Caption := 'TStrings UTF8 存取';
　Button4.Caption := 'TFileStream 默認存取';
　Button5.Caption := 'TFileStream ASCII 存取';
　Button6.Caption := 'TFileStream UTF8存取';
　Button7.Caption := 'TMemoryStream 默認存取';
　Button8.Caption := 'TMemoryStream ASCII 存取';
　Button9.Caption := 'TMemoryStream UTF8 存取';
end;
procedure TForm1.Button1Click(Sender: TObject);
var
　List: TStrings;
begin
　List := TStringList.Create;
　List.Text := str;
　List.SaveToFile(FilePath);
　List.LoadFromFile(FilePath);
　Memo2.Lines := List;
　List.Free;
end;
procedure TForm1.Button2Click(Sender: TObject);
var
　List: TStrings;
begin
　List := TStringList.Create;
　List.Text := str;
　List.SaveToFile(FilePath, TEncoding.ASCII);
　List.LoadFromFile(FilePath, TEncoding.ASCII);
　Memo2.Lines := List;
　List.Free;
end;
procedure TForm1.Button3Click(Sender: TObject);
var
　List: TStrings;
begin
　List := TStringList.Create;
　List.Text := str;
　List.SaveToFile(FilePath, TEncoding.UTF8);
　List.LoadFromFile(FilePath, TEncoding.UTF8);
　Memo2.Lines := List;
　List.Free;
end;
procedure TForm1.Button4Click(Sender: TObject);
var
　stream: TStream;
begin
　stream := TFileStream.Create(FilePath, fmCreate);
　Memo1.Lines.SaveToStream(stream);
　stream.Position := 0;
　Memo2.Lines.LoadFromStream(stream);
　stream.Free;
end;
procedure TForm1.Button5Click(Sender: TObject);
var
　stream: TStream;
begin
　stream := TFileStream.Create(FilePath, fmCreate);
　Memo1.Lines.SaveToStream(stream, TEncoding.ASCII);
　stream.Position := 0;
　Memo2.Lines.LoadFromStream(stream, TEncoding.ASCII);
　stream.Free;
end;
procedure TForm1.Button6Click(Sender: TObject);
var
　stream: TStream;
begin
　stream := TFileStream.Create(FilePath, fmCreate);
　Memo1.Lines.SaveToStream(stream, TEncoding.UTF8);
　stream.Position := 0;
　Memo2.Lines.LoadFromStream(stream, TEncoding.UTF8);
　stream.Free;
end;
procedure TForm1.Button7Click(Sender: TObject);
var
　stream: TMemoryStream;
begin
　stream := TMemoryStream.Create;
　Memo1.Lines.SaveToStream(stream);
　stream.SaveToFile(FilePath);
　stream.LoadFromFile(FilePath);
　stream.Position := 0;
　Memo2.Lines.LoadFromStream(stream);
　stream.Free;
end;
procedure TForm1.Button8Click(Sender: TObject);
var
　stream: TMemoryStream;
begin
　stream := TMemoryStream.Create;
　Memo1.Lines.SaveToStream(stream, TEncoding.ASCII);
　stream.SaveToFile(FilePath);
　stream.LoadFromFile(FilePath);
　stream.Position := 0;
　Memo2.Lines.LoadFromStream(stream, TEncoding.ASCII);
　stream.Free;
end;
procedure TForm1.Button9Click(Sender: TObject);
var
　stream: TMemoryStream;
begin
　stream := TMemoryStream.Create;
　Memo1.Lines.SaveToStream(stream, TEncoding.UTF8);
　stream.SaveToFile(FilePath);
　stream.LoadFromFile(FilePath);
　stream.Position := 0;
　Memo2.Lines.LoadFromStream(stream, TEncoding.UTF8);
　stream.Free;
end;
end.窗體文件:object Form1: TForm1
　Left = 0
　Top = 0
　Caption = 'Form1'
　ClIEntHeight = 103
　ClIEntWidth = 686
　Color = clBtnFace
　Font.Charset = DEFAULT_CHARSET
　Font.Color = clWindowText
　Font.Height = -11
　Font.Name = 'Tahoma'
　Font.Style = []
　OldCreateOrder = False
　OnCreate = FormCreate
　PixelsPerInch = 96
　TextHeight = 13
　object Button1: TButton
　　Left = 117
　　Top = 8
　　Width = 150
　　Height = 25
　　Caption = 'Button1'
　　TabOrder = 0
　　OnClick = Button1Click
　end
　object Button2: TButton
　　Left = 268
　　Top = 8
　　Width = 150
　　Height = 25
　　Caption = 'Button2'
　　TabOrder = 1
　　OnClick = Button2Click
　end
　object Button3: TButton
　　Left = 419
　　Top = 8
　　Width = 150
　　Height = 25
　　Caption = 'Button3'
　　TabOrder = 2
　　OnClick = Button3Click
　end
　object Button4: TButton
　　Left = 117
　　Top = 39
　　Width = 150
　　Height = 25
　　Caption = 'Button4'
　　TabOrder = 3
　　OnClick = Button4Click
　end
　object Memo1: TMemo
　　Left = 0
　　Top = 0
　　Width = 116
　　Height = 103
　　Align = alLeft
　　Lines.Strings = (
　　　'Hello World'
　　　#19990#30028#24744#22909
　　　#12495#12525#12540#19990#30028
　　　#50668#47084#48516', '#50504#45397#54616#49464#50836
　　　'Ol'#225' Mundo'
　　　#1055#1088#1080#1074#1077#1090' '#1084#1080#1088)
　　TabOrder = 4
　end
　object Memo2: TMemo
　　Left = 570
　　Top = 0
　　Width = 116
　　Height = 103
　　Align = alRight
　　Lines.Strings = (
　　　'Memo2')
　　TabOrder = 5
　　ExplicitLeft = 578
　end
　object Button5: TButton
　　Left = 268
　　Top = 39
　　Width = 150
　　Height = 25
　　Caption = 'Button5'
　　TabOrder = 6
　　OnClick = Button5Click
　end
　object Button6: TButton
　　Left = 419
　　Top = 39
　　Width = 150
　　Height = 25
　　Caption = 'Button6'
　　TabOrder = 7
　　OnClick = Button6Click
　end
　object Button7: TButton
　　Left = 117
　　Top = 70
　　Width = 150
　　Height = 25
　　Caption = 'Button7'
　　TabOrder = 8
　　OnClick = Button7Click
　end
　object Button8: TButton
　　Left = 268
　　Top = 70
　　Width = 150
　　Height = 25
　　Caption = 'Button8'
　　TabOrder = 9
　　OnClick = Button8Click
　end
　object Button9: TButton
　　Left = 419
　　Top = 70
　　Width = 150
　　Height = 25
　　Caption = 'Button9'
　　TabOrder = 10
　　OnClick = Button9Click
　end
end