本例效果图:
<?xml version="1.0" standalone="yes"?>
<DATAPACKET Version="2.0">
<METADATA>
<FIELDS>
<FIELD attrname="Name" fieldtype="string" WIDTH="24"/>
<FIELD attrname="Capital" fieldtype="string" WIDTH="24"/>
<FIELD attrname="Continent" fieldtype="string" WIDTH="24"/>
<FIELD attrname="Area" fieldtype="r8"/>
<FIELD attrname="Population" fieldtype="r8"/>
</fields>
<PARAMS DEFAULT_ORDER="1" PRIMARY_KEY="1" LCID="2057"/>
</metadata>
<ROWDATA>
<ROW Name="Argentina" Capital="Buenos Aires" Continent="South America" Area="2777815" Population="32300003"/>
<ROW Name="Bolivia" Capital="La Paz" Continent="South America" Area="1098575" Population="7300000"/>
<ROW Name="Brazil" Capital="Brasilia" Continent="South America" Area="8511196" Population="150400000"/>
<ROW Name="Canada" Capital="Ottawa" Continent="North America" Area="9976147" Population="26500000"/>
<ROW Name="Chile" Capital="Santiago" Continent="South America" Area="756943" Population="13200000"/>
<ROW Name="Colombia" Capital="Bagota" Continent="South America" Area="1138907" Population="33000000"/>
<ROW Name="Cuba" Capital="Havana" Continent="North America" Area="114524" Population="10600000"/>
<ROW Name="Ecuador" Capital="Quito" Continent="South America" Area="455502" Population="10600000"/>
<ROW Name="El Salvador" Capital="San Salvador" Continent="North America" Area="20865" Population="5300000"/>
<ROW Name="Guyana" Capital="Georgetown" Continent="South America" Area="214969" Population="800000"/>
<ROW Name="Jamaica" Capital="Kingston" Continent="North America" Area="11424" Population="2500000"/>
<ROW Name="Mexico" Capital="Mexico City" Continent="North America" Area="1967180" Population="88600000"/>
<ROW Name="Nicaragua" Capital="Managua" Continent="North America" Area="139000" Population="3900000"/>
<ROW Name="Paraguay" Capital="Asuncion" Continent="South America" Area="406576" Population="4660000"/>
<ROW Name="Peru" Capital="Lima" Continent="South America" Area="1285215" Population="21600000"/>
<ROW Name="United States of America" Capital="Washington" Continent="North America" Area="9363130" Population="249200000"/>
<ROW Name="Uruguay" Capital="Montevideo" Continent="South America" Area="176140" Population="3002000"/>
<ROW Name="Venezuela" Capital="Caracas" Continent="South America" Area="912047" Population="19700000"/>
</rowdata>
</datapacket>
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, Grids, DBGrids, DB, DBClient, StdCtrls, ComCtrls, ExtCtrls;
type
TForm1 = class(TForm)
DataSource1: TDataSource;
ClientDataSet1: TClientDataSet;
DBGrid1: TDBGrid;
TreeView1: TTreeView;
Splitter1: TSplitter;
procedure FormCreate(Sender: TObject);
procedure TreeView1Change(Sender: TObject; Node: TTreeNode);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.FormCreate(Sender: TObject);
var
i: Integer;
node: TTreeNode;
List: TStringList;
s: string;
begin
{country.xml 是 Delphi 的数据示范文件, 也可以用 country.cds}
ClientDataSet1.FileName := 'c:\temp\country.xml';
ClientDataSet1.Active := True;
DataSource1.DataSet := ClientDataSet1;
DBGrid1.DataSource := DataSource1;
{上面四行是让数据构件互相挂接, 也可以在设计时设定}
{建立 List}
List := TStringList.Create;
List.Sorted := True; {指定排序}
List.Duplicates := dupIgnore; {避免重复}
{把数据加入到 TreeView}
for i := 0 to ClientDataSet1.FieldDefs.Count - 1 do
begin
node := TreeView1.Items.Add(nil, ClientDataSet1.FieldDefs[i].Name); {字段名}
{为避免数据重复, 先把数据给 List}
List.Clear;
ClientDataSet1.First;
while not ClientDataSet1.Eof do
begin
List.Add(ClientDataSet1.Fields[i].value);
ClientDataSet1.Next;
end;
{把 List 中的数据加入到 TreeView}
for s in List do TreeView1.Items.AddChild(node, s);
end;
List.Free;
end;
procedure TForm1.TreeView1Change(Sender: TObject; Node: TTreeNode);
begin
if Node.Parent <> nil then
begin
{下面的 Filter 其实就是 SQL 查询语句, 如果用其他数据库替换就是}
ClientDataSet1.Filter := Node.Parent.Text + '=''' + Node.Text + '''';
ClientDataSet1.Filtered := True;
end else ClientDataSet1.Filtered := False; {选字段名时取消过虑}
end;
end.
附数据库样本:
