关于 Delphi 中流的使用(5) 组件序列化

unit Unit1;

interface

uses

Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

Dialogs, StdCtrls;

type

TForm1 = class(TForm)

Button1: TButton;

Button2: TButton;

Button3: TButton;

Button4: TButton;

Memo1: TMemo;

procedure Button1Click(Sender: TObject);

procedure Button2Click(Sender: TObject);

procedure Button3Click(Sender: TObject);

procedure Button4Click(Sender: TObject);

private

{ Private declarations }

public

{ Public declarations }

end;

var

Form1: TForm1;

implementation

{$R *.dfm}

//添加一个 Memo1 然后修改其内容

procedure TForm1.Button1Click(Sender: TObject);

begin

WriteComponentResFile('c:\temp\memo.dat', Memo1);

{只此一句就可以把当前的 Memo 的状态序列化到文件}

end;

//反序列化, 读回

procedure TForm1.Button2Click(Sender: TObject);

begin

ReadComponentResFile('c:\temp\memo.dat', Memo1);

{一句话就可以读回, 不管是经过了什么操作(甚至是关机)}

end;

{

这好像和流没什么关系, 其实这就是流的典型操作,

WriteComponentResFile 和 ReadComponentResFile 分别调用了流类的

WriteComponentRes 与 ReadComponentRes 方法.

下面用更直接的流的方式重新实现一次:

}

//序列化

procedure TForm1.Button3Click(Sender: TObject);

var

stream: TStream;

const

strPath = 'c:\temp\m.dat';

begin

stream := TFileStream.Create(strPath, fmCreate);

stream.WriteComponentRes(Memo1.ClassName, Memo1);

{WriteComponentRes 有两个参数: 文件名和组件名}

stream.Free;

end;

//反序列化

procedure TForm1.Button4Click(Sender: TObject);

var

stream: TStream;

const

strPath = 'c:\temp\m.dat';

begin

stream := TFileStream.Create(strPath, fmOpenRead);

stream.ReadComponentRes(Memo1);

{ReadComponentRes 只有一个参数: 组件名}

stream.Free;

end;

end.