摘自一位网友的代码--树

 

未经验证

 

 

unit uCGoodsClass;

interface
  uses
    Windows,Messages,SysUtils,Variants,Classes,ComCtrls,DBClient,DB,UnDBSCKT;
  type
    TuCGoodsClass=class(TObject)
    private
    public
      function    GetAllTreeNode():OleVariant;
      function    ModYData(item:string;id,parent_id:Integer):Integer;
      function    ADDData(item_name:string;parent_id:integer):integer;
      function    DelData(id:integer):integer;
      procedure   ShowAllTree(MyTree:TTreeview);
    end;
implementation

function TuCGoodsClass.GetAllTreeNode():OleVariant;
var
  DBopreator:TDBSCKT;
  StrSql:string;
  Res_Data:OleVariant;
begin
  Res_Data:=Null;
  DBopreator:=TDBSCKT.Create(nil);
  strsql:=' 1=1 order by id asc';
  Res_Data:=DBopreator.GetQuery('Goods_Class',StrSql);
  FreeAndNil(DBopreator);
  Result:=Res_Data;
end;

procedure CreateClassTree(MYCds:TClientDataSet;parent_id:Integer;root:TTreeNode;MyTree:TTreeView);
type
  PTreeClassNode = ^TTreeClassNode;   //用于存储每个树形节点的当前ID号和它的父的ID号。
  TTreeClassNode = record
    Cur_id    :integer; //当前ID
    Parent_id :Integer; //父类的ID
  end;
var
  ChildNode:TTreeNode;
  Add_Node_Str: string;
  PCur_Class_Node: PTreeClassNode;
  i,next_parent_id:integer;
begin
  if MYCds.Active then
    begin
      MYCds.Filtered:=False;
      MYCds.Filter:='parent_id='+inttostr(parent_id);
      MYCds.Filtered:=True;
      if MYCds.RecordCount>0 then
        for i:=0 to MYcds.RecordCount-1 do
          begin
            Add_Node_Str:=Trim(MYCds.FieldByName('item_name').AsString);
            ChildNode:=MyTree.Items.AddChild(root,Add_Node_Str);
            New(PCur_Class_Node);
            PCur_Class_Node.Cur_id:=MYCds.FieldByName('id').AsInteger;
            PCur_Class_Node.Parent_id:=MYCds.FieldByName('parent_id').AsInteger;
            ChildNode.Data:=PCur_Class_Node;
            MYCds.Next;
          end;
     if root<>nil then
      begin
        ChildNode:=root.GetNext;
        if ChildNode <> nil then
          begin
            next_parent_id:=PTreeClassNode(ChildNode.Data).Cur_id;
            CreateClassTree(MYCds,next_parent_id,ChildNode,MyTree);
          end;
      end;
    end;

end;

procedure TuCGoodsClass.ShowAllTree(MyTree:TTreeView);
var
  Cds :TClientDataSet;
  Root:TTreeNode;
begin
   cds:=TClientDataSet.Create(nil);
   CDS.Name:='tempcds';
   CDS.FetchOnDemand:=False;
   CDS.PacketRecords:=-1;
   Cds.Data:=GetAllTreeNode();
   if not cds.IsEmpty then
     begin
       Root:=MyTree.Items.GetFirstNode;
       CreateClassTree(Cds,0,Root,MyTree);
     end;
   FreeAndNil(Cds);
end;

function TuCGoodsClass.ModyData(item:string;id,parent_id:Integer):Integer;
var
  DBopreator:TDBSCKT;
  Res_Flage:Integer;
begin
  //Res_Flage:=0;
  DBopreator:=TDBSCKT.Create(nil);
  Res_Flage:=DBopreator.UpdateSingleData('Goods_class',['item_name','parent_id'],[item,parent_id],' id='+inttostr(id));
  FreeAndNil(DBopreator);
  Result:=Res_Flage;
end;

function TuCGoodsClass.DelData(id:integer):Integer;
var
  DBopreator:TDBSCKT;
  Res_Flage:Integer;
begin
  //Res_Flage:=0;
  DBopreator:=TDBSCKT.Create(nil);
  Res_Flage:=DBopreator.DeleteSingleData('Goods_class','id='+inttostr(Id));
  FreeAndNil(DBopreator);
  Result:=Res_Flage;
end;

function TuCGoodsClass.AddData(item_name:string;parent_id:Integer):integer;
var
  DBopreator:TDBSCKT;
  Res_Flage:Integer;
begin
  //Res_Flage:=0;
  DBopreator:=TDBSCKT.Create(nil);
  Res_Flage:=DBopreator.InsertSingleData('Goods_Class',['item_name','parent_id'],[item_name,parent_id],True);
  FreeAndNil(DBopreator);
  Result:=Res_Flage;
end;
end.