学习 TTreeView [6] - SaveToFile、LoadFromStream、SaveToStream、LoadFromFile

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, ComCtrls, StdCtrls, Grids, ExtCtrls;

type
TForm1 = class(TForm)
TreeView1: TTreeView;
Memo1: TMemo;
Panel1: TPanel;
Button1: TButton;
Button2: TButton;
Button3: TButton;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

{初始化 TreeView1}
procedure TForm1.FormCreate(Sender: TObject);
var
Nodes: TTreeNodes;
node: TTreeNode;
begin
TreeView1.Align := alLeft;
Nodes := TreeView1.Items;
node := Nodes.Add(nil, '一连长');
node := Nodes.AddChild(node, '一排长');
node := Nodes.AddChild(node, '一班长');
node := Nodes.AddChild(node, '战士1');
Nodes.Add(node, '战士2');
Nodes.Add(node, '战士3');
Nodes.Add(node, '战士4');
node := node.Parent;
Nodes.Add(node, '二班长');
Nodes.Add(node, '三班长');
node := node.Parent;
Nodes.Add(node, '二排长');
Nodes.Add(node, '三排长');
node := node.Parent;
Nodes.Add(node, '二连长');
Nodes.Add(node, '三连长');
end;

{保存到文件}
procedure TForm1.Button1Click(Sender: TObject);
const
path = 'c:\temp\tree.txt';
begin
TreeView1.SaveToFile(path);
TButton(Sender).Caption := '保存';
end;

{从文件中载入}
procedure TForm1.Button2Click(Sender: TObject);
const
path = 'c:\temp\tree.txt';
begin
if FileExists(path) then TreeView1.LoadFromFile(path);
TButton(Sender).Caption := '载入';
end;

{从流中读取}
procedure TForm1.Button3Click(Sender: TObject);
var
stream: TStream;
begin
stream := TMemoryStream.Create;
try
Memo1.Lines.SaveToStream(stream);
stream.Position := 0;
TreeView1.LoadFromStream(stream);
finally
stream.Free;
end;
end;

end.