如何让 TreeView 的列表项携带数据、并读出或删除这个数据 - 回复 "Splendour" 的问题

问题来源: http://www.cnblogs.com/del/archive/2009/12/18/1627110.html#1799657

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准备工作:
1、在空白窗体上添加 TreeView1 和 Button1
2、激活窗体的 OnCreate 事件, 激活 TreeView 的 OnDblClick 事件

全部代码如下:

---

unit Unit1;



interface



uses

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

  Dialogs, ComCtrls, StdCtrls;



type

  TForm1 = class(TForm)

    TreeView1: TTreeView;

    Button1: TButton;

    procedure FormCreate(Sender: TObject);

    procedure TreeView1DblClick(Sender: TObject);

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}



var

  arr1,arr2,arr3: array of TPoint;



procedure TForm1.FormCreate(Sender: TObject);

var

  i: Integer;

begin

  {准备测试用的动态数组数据}

  SetLength(arr1, 2);

  SetLength(arr2, 3);

  SetLength(arr3, 4);

  for i := 0 to Length(arr1)-1 do begin arr1[i].X := i+1; arr1[i].Y := i+4; end;

  for i := 0 to Length(arr2)-1 do begin arr2[i].X := i+2; arr2[i].Y := i+5; end;

  for i := 0 to Length(arr3)-1 do begin arr3[i].X := i+3; arr3[i].Y := i+6; end;



  {添加到 TreeView}

  TreeView1.Items.Clear;

  TreeView1.Items.AddChildObject(nil, 'Note1', arr1);

  TreeView1.Items.AddChildObject(nil, 'Note2', arr2);

  TreeView1.Items.AddChildObject(nil, 'Note3', arr3);



  Button1.Caption := '重新装载数据';

  Button1.OnClick := OnCreate;

end;



procedure TForm1.TreeView1DblClick(Sender: TObject);

var

  node: TTreeNode;

  arr: array of TPoint;

begin

  {获取当前节点}

  node := TreeView1.Selected;

  if not Assigned(node.Data) then

  begin

    ShowMessageFmt('%s 中没有携带其他数据', [node.Text]);

    Exit;

  end;



  {获取数组}

  arr := node.Data;

  {读取数组的第一个数据}

  ShowMessageFmt('%d, %d', [arr[0].X, arr[0].Y]);

  {清除数据指针}

  node.Data := nil;

  ShowMessageFmt('%s 中的数据已被删除!', [node.Text]);

end;



end.