怎么样动态生成treeview?

Question

我有四个层次：科目、章、节、知识点
运行的时候我想从数据库中把查询到的结果显示在树形目录中，不知道怎么做？
能不能给出一段实例代码？

Answer 1

给你一段代码参考：
var id1,id2,id3:Integer;
    bootnode,tnode1,tnode2,tnode3:ttreenode;
begin
    bootnode:=Dest_TreeView.Items.Add(Nil,'科目');    bootnode.ImageIndex:=1;
    bootnode.SelectedIndex:=0;
    Temp_Query1.Close;
    Temp_Query1.SQL.Clear;
    Temp_Query1.SQL.Add('Select * From T_KM Where (code like '''+Source_code+'%'') and (Len(code)=4)');
    Temp_Query1.Open;
    For id1:=1 To Temp_Query1.RecordCount Do
    Begin
        tnode1:=Dest_TreeView.Items.AddChild(bootnode,'('+Temp_Query1.FieldByName('code').AsString+')'+
                Temp_Query1.FieldByName('name').AsString);
        tnode1.ImageIndex:=1;
        tnode1.SelectedIndex:=0;
        Temp_Query2.Close;
        Temp_Query2.SQL.Clear;
        Temp_Query2.SQL.Add('Select * From T_KM Where (code like '''+Temp_Query1.FieldByName('code').AsString+
                            '%'') and (Len(code)=6)');
        Temp_Query2.Open;
        For id2:=1 To Temp_Query2.RecordCount Do
        Begin
            tnode2:=Dest_TreeView.Items.AddChild(tnode1,'('+Temp_Query2.FieldByName('code').AsString+')'+
                    Temp_Query2.FieldByName('name').AsString);
            tnode2.ImageIndex:=1;
            tnode2.SelectedIndex:=0;
            Temp_Query3.Close;
            Temp_Query3.SQL.Clear;
            Temp_Query3.SQL.Add('Select distinct zsd1 From T_STTK where stid like '''+
                                Temp_Query2.FieldByName('code').AsString+'%''');
            Temp_Query3.Open;
            For id3:=1 To Temp_Query3.RecordCount Do
            Begin
                tnode3:=Dest_TreeView.Items.AddChild(tnode2,Temp_Query3.FieldByName('zsd1').AsString);
                tnode3.ImageIndex:=2;
                tnode3.SelectedIndex:=2;
                Temp_Query3.Next;
            End;
            Temp_Query3.Close;
            Temp_Query2.Next;
        End;
        Temp_Query2.Close;
        Temp_Query1.Next;
    End;
    Temp_Query1.Close;end;

Answer 2

参考一下：
type
  PMyRec = ^TMyRec;
  TMyRec = record
    pgh: string;
    pghmc: string;
    pghlb1mc: string;
    pghlb2mc: string;
    pghlb1: string;
    pghlb2: string;
    level: string;
  end;
procedure TfyxmbF.GetXmTv;
procedure TQueryF.SetPghTree;
var
  TmpQuery, TmpQuery1, TmpQuery2: TQuery;
  i, j: Integer;
  TmpNode: TTreeNode;
  MyRecPtr: PMyRec;
begin
  TmpQuery := TQuery.Create(nil);
  TmpQuery1 := TQuery.Create(nil);
  TmpQuery2 := TQuery.Create(nil);
  TmpQuery.DatabaseName := Query1.DatabaseName;
  TmpQuery1.DatabaseName := Query1.DatabaseName;
  TmpQuery2.DatabaseName := Query1.DatabaseName;
  try
    TmpQuery.DatabaseName := Query1.DatabaseName;
    TmpQuery.SQL.Text := 'SELECT DISTINCT PGHLB1MC,PGHLB1 FROM CBBPMGG ORDER BY PGHLB1';
    TmpQuery.Open;
    TV_PGH.items.Clear;
    new(MyRecPtr);
    MyRecPtr^.level := '0';
    MyRecPtr^.pghlb2mc := '所有品种'; //派工号类别2名称
    TV_PGH.Items.AddChildObject(nil, MyRecPtr^.pghlb2mc, MyRecPtr);
    TV_PGH.Items[0].StateIndex := 1;
    TV_PGH.Items.BeginUpdate;
    for i := 0 to TmpQuery.RecordCount - 1 do
    begin //类别
      new(MyRecPtr);
      MyRecPtr^.level := '1';
      MyRecPtr^.pghlb2mc := TmpQuery.Fields[0].AsString;
      TmpNode := TV_PGH.Items.AddChildObject(TV_PGH.TopItem, MyRecPtr^.pghlb2mc, MyRecPtr);
      TmpQuery1.Close;
      TmpQuery1.SQL.Text :=
        'SELECT PGHLB2MC,PGHLB2 FROM CBBPMGG WHERE PGHLB1= ' + #39 +
        TmpQuery.Fields[1].AsString + #39 + ' ORDER BY PGHLB2';
      TmpQuery1.Open;
      for j := 0 to TmpQuery1.RecordCount - 1 do
      begin //品种
        new(MyRecPtr);
        MyRecPtr^.level := '2';
        MyRecPtr^.pghlb2 := TmpQuery1.Fields[1].AsString; //派工号类别2
        MyRecPtr^.pghlb2mc := TmpQuery1.Fields[0].AsString; //派工号类别2名称
        TV_PGH.Items.AddChildObject(TmpNode, MyRecPtr^.pghlb2mc, MyRecPtr);
        TmpQuery1.Next;
      end;
      TmpQuery.Next;
    end;
    TV_PGH.Items.EndUpdate;
  finally
    TmpQuery1.Free;
    TmpQuery.Free;
  end;
end;

Answer 3

procedure TForm1.Button1Click(Sender: TObject);
var
  i,j,m,n:integer;
  s1,s2,s3,s4:string;
  node,subnode1,subnode2,subnode3:TTreeNode;
  i1,n1,i2,n2,i3,n3:integer;
begin
  i1:=0;
  i2:=0;
  i3:=0;
  form1.Table1.Open;
  form1.Table1.First;
  i:=form1.Table1.RecordCount;
  if i>0 then
  begin
    for j:=0 to i-1 do
    begin
      s1:=form1.Table1.FieldValues['km'];
      s2:=form1.Table1.FieldValues['zh'];
      s3:=form1.Table1.FieldValues['jie'];
      s4:=form1.Table1.FieldValues['zsd'];
      m:=form1.TreeView1.Items.Count;
      if m>0 then
      begin
        for n:=0 to m-1 do
        begin
          if form1.TreeView1.Items.Item[n].Text=s1 then
          begin
            i1:=i1+1;
            n1:=n;
          end;
        end;
        if i1=1 then
        begin
          for n:=0 to m-1 do
          begin
            if (form1.TreeView1.Items.Item[n].Text=s2) and (form1.TreeView1.Items.Item[n].Parent.Text=s1) then
            begin
              i2:=i2+1;
              n2:=n;
            end;
          end;
          if i2=1 then
          begin
            for n:=0 to m-1 do
            begin
              if (form1.TreeView1.Items.Item[n].Text=s3) and (form1.TreeView1.Items.Item[n].Parent.Text=s2) and (form1.TreeView1.Items.Item[n].Parent.Parent.Text=s1) then
              begin
                i3:=i3+1;
                n3:=n;
              end;
            end;
            if i3=1 then
            begin
              subnode3:=form1.TreeView1.Items.AddChild(form1.TreeView1.Items.Item[n3],s4);
            end
            else
            begin
              subnode2:=form1.TreeView1.Items.AddChild(form1.TreeView1.Items.Item[n2],s3);
              subnode3:=form1.TreeView1.Items.AddChild(subnode2,s4);
            end;
          end
          else
          begin
            subnode1:=form1.TreeView1.Items.AddChild(form1.TreeView1.Items.Item[n1],s2);
            subnode2:=form1.TreeView1.Items.AddChild(subnode1,s3);
            subnode3:=form1.TreeView1.Items.AddChild(subnode2,s4);
          end;
        end
        else
        begin
          node:=form1.TreeView1.Items.Add(nil,s1);
          subnode1:=form1.TreeView1.Items.AddChild(node,s2);
          subnode2:=form1.TreeView1.Items.AddChild(subnode1,s3);
          subnode3:=form1.TreeView1.Items.AddChild(subnode2,s4);
        end;
      end
      else
      begin
        node:=form1.TreeView1.Items.Add(nil,s1);
        subnode1:=form1.TreeView1.Items.AddChild(node,s2);
        subnode2:=form1.TreeView1.Items.AddChild(subnode1,s3);
        subnode3:=form1.TreeView1.Items.AddChild(subnode2,s4);
      end;
      form1.Table1.Next;
    end;
  end;
end;

Answer 4

我自己以前的一段代码：procedure TForm1.FormCreate(Sender: TObject);
 var
  node1,node2,node3,node4:TTreenode;
  i,ii,iii:integer;
  glass1,class1 :string;
begin
    treeview1.Items.Clear;
    node1:=treeview1.Items.Add(nil,'ѧУ');
    node1.ImageIndex:=0;
    query1.Open;
    for i:=1 to query1.RecordCount do
    begin
     node2:=treeview1.Items.AddChild(node1,query1.FieldByName('glass').Value);
     node2.ImageIndex:=1;
     query2.Close;
     query2.SQL.Clear;
     query2.SQL.Add('select * from class where glass='+#39+query1.FieldByName('glass').Value+#39);
     query2.Open;
     for ii:=1 to query2.RecordCount do
      begin
       node3:=treeview1.Items.AddChild(node2,query2.FieldByName('class').Value);
       node3.ImageIndex:=2;
       query3.Close;
       query3.SQL.Clear;
       query3.SQL.Add('select * from student where glass='+#39+query1.FieldByName('glass').Value+#39+'and class='+#39+query2.FieldByName('class').Value+#39);
       query3.Open;
       for iii:=1 to query3.RecordCount do
       begin
       node4:=treeview1.Items.AddChild(node3,query3.FieldByName('name_student').Value);
       node4.ImageIndex:=3;
       query3.Next;
       end;
       query2.Next;
       end;
       query1.Next;
     end;
end;