本例效果图:

unit Unit1;interfaceusesWindows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,Dialogs, ComCtrls, StdCtrls, Grids, ExtCtrls;typeTForm1 = class(TForm)TreeView1: TTreeView;Button1: TButton;Button2: TButton;Button3: TButton;Button4: TButton;procedure Button1Click(Sender: TObject);procedure Button2Click(Sender: TObject);procedure Button3Click(Sender: TObject);procedure Button4Click(Sender: TObject);procedure Button5Click(Sender: TObject);procedure FormCreate(Sender: TObject);end;varForm1: TForm1;implementation{$R *.dfm}procedure TForm1.FormCreate(Sender: TObject);
varNodes: TTreeNodes;node: TTreeNode;
beginTreeView1.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;{初始化}
procedure TForm1.Button1Click(Sender: TObject);
beginTreeView1.Items.Clear;FormCreate(nil);TButton(Sender).Caption := '初始化';
end;{删除}
procedure TForm1.Button2Click(Sender: TObject);
varnode: TTreeNode;
beginif not Boolean(TreeView1.Items) then Exit; {如果 TreeView1 无内容}if TreeView1.SelectionCount = 0 then Exit; {如果无选择}node := TreeView1.Selected;node.Delete;TButton(Sender).Caption := '删除';
end;{删除它的所有下级}
procedure TForm1.Button3Click(Sender: TObject);
varnode: TTreeNode;
beginif not Boolean(TreeView1.Items) then Exit;if TreeView1.SelectionCount = 0 then Exit;node := TreeView1.Selected;if node.HasChildren then node.DeleteChildrenelse ShowMessage(node.Text + ' 没有下级');TButton(Sender).Caption := '删除下级';
end;{用 TTreeNodes 删除}
procedure TForm1.Button4Click(Sender: TObject);
varnode: TTreeNode;
beginif not Boolean(TreeView1.Items) then Exit;if TreeView1.SelectionCount = 0 then Exit;node := TreeView1.Selected;TreeView1.Items.Delete(node);TButton(Sender).Caption := '用 TTreeNodes 删除';
end;{插入, 只能通过 TTreeNodes}
procedure TForm1.Button5Click(Sender: TObject);
varnode: TTreeNode;
beginif not Boolean(TreeView1.Items) then Exit;if TreeView1.SelectionCount = 0 then Exit;node := TreeView1.Selected;TreeView1.Items.Insert(node, '新成员');TButton(Sender).Caption := '插入';
end;end.