node(id1, depart1, parentid1); //开始递归
               j:=0;
               parentnode:=nil;
               isfind1:=false;
               for j:=0 to tv1.Items.Count-1 do
                 if parentid = integer(tv1.Items.item[j].Data) then
                   begin
                     isfind1:=True;
                     parentnode:=tv1.Items.Item[j];
                     Break;
                   end;
               if isfind1 then
                 tv1.Items.addchildobject(parentnode,trim(depart),pointer(id))
             end;
         end;
end;

 

2.按照层次建树，（数据表中有一个字段记录每一个节点在数上的深度，先建根节点，再第一层，第二层）

procedure TForm1.createtree(Sender: TObject);
var
   sqlstr:string;
   i:Integer;
   rootnode,parentnode:TTreeNode;
begin
   adoquery1.Close;
   ADOQuery1.SQL.Clear;
   sqlstr:=''select * from tdepart order by depth'';
   ADOQuery1.SQL.Add(sqlstr);
   ADOQuery1.Open;
   ADOQuery1.First;
   while not ADOQuery1.Eof do
     begin
       if ADOQuery1.fieldbyname(''parentid'').Asinteger = 0 then
         rootnode:=tv1.Items.addchildobject(nil,trim(ADOQuery1.fieldbyname(''departname'').AsString),
                                            pointer(ADOQuery1.fieldbyname(''id'').Asinteger))
       else
         begin
           i:=0;
           parentnode:=nil;
         &n