TreeView和ListView数据库查询数据联动操作

2021/6/30 19:23:55

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好久不用了,重新整理下放这里以备需要使用,功能见图

定义TreeView addObject中data存储的记录集

type
  PNode = ^TNode;

  TNode = record
    id: Integer;
    tcmc: string;
    mxid: string;
  end;

填充TreeView代码

procedure TForm1.FillTree(TreeView: TTreeView);
var
  findq: TADOQuery;
  node: TTreeNode;
  p: PNode;
  //这个方法是根据记录的id字段值,查找TreeView上的父节点
  function FindParentNode(id: Integer): TTreeNode;
  var
    i: Integer;
  begin
    Result := nil;
    for i := 0 to TreeView.Items.Count - 1 do
    begin
      //比较Node的Data值和记录的id值
      if Integer(PNode(TreeView.Items[i].Data).id) = id then
      begin
        Result := TreeView.Items[i];
        Break;
      end;
    end;
  end;

begin
  findq := TADOQuery.Create(nil);
  findq.ConnectionString := 'Provider=SQLOLEDB.1;Password=Sa123;Persist Security Info=True;User ID=demo;Initial Catalog=dd;Data Source=127.0.0.1';
  try
    TreeView.Items.BeginUpdate;
    TreeView.Items.Clear;
    findq.SQL.Text := 'SELECT c.id,c.tcmc,c.pid,c.mxid FROM 处方套餐 AS c WITH(NOLOCK) ORDER BY c.id';
    findq.Open;
    while not findq.Eof do
    begin
      //将数据放入结构体以便双击时使用
      New(p);
      p.id := findq.FieldByName('id').AsInteger;
      p.tcmc := findq.FieldByName('tcmc').AsString;
      p.mxid := findq.FieldByName('mxid').AsString;
      //如果是最顶级,直接添加到TreeView
      if findq.FieldByName('pid').AsInteger = 0 then
        //将导航树保存在Node的Data中,以便查找用
        TreeView.Items.AddObject(nil, findq.FieldByName('tcmc').AsString, TObject(p))
      else
      begin
        //查找上级节点,存在上级节点添加子节点
        node := FindParentNode(findq.FieldByName('pid').AsInteger);
        if node <> nil then
          TreeView.Items.AddChildObject(node, findq.FieldByName('tcmc').AsString, TObject(p));
      end;
      findq.Next;
    end;
  finally
    findq.Free;
    TreeView.FullExpand;     //展开树
    TreeView.Items.EndUpdate;
  end;
end;

查询数据调用代码

procedure TForm1.Button1Click(Sender: TObject);
begin
  FillTree(TreeView1);
end;

双击TreeView填充ListView

procedure TForm1.TreeView1DblClick(Sender: TObject);
var
  mxid: string;
  str: TStrings;
  I: Integer;
  strSql: TStrings;
  QryTemp: TADOQuery;
begin
  if not TreeView1.Selected.HasChildren then      //当前选中是否含有子项,如果有则展开不执行操作
  begin
    str := TStringList.Create;
    strSql := TStringList.Create;
    QryTemp := TADOQuery.Create(Self);
    try
      QryTemp.ConnectionString := 'Provider=SQLOLEDB.1;Password=Sa123;Persist Security Info=True;User ID=demo;Initial Catalog=dd;Data Source=127.0.0.1';
      //mxid值:107,108,109,110,111,112
      mxid := PNode(TreeView1.Items[TreeView1.Selected.AbsoluteIndex].Data).mxid;
      //根据分割符号添加mxid到StringList
      str.Delimiter := ',';
      str.DelimitedText := mxid;
      //查询数据
      strSql.Clear;
      strSql.Add('SELECT a.DiagnosisProjectID, a.DiagnosisProjectName');
      strSql.Add('FROM   DDDiagnosisProject AS a WITH(NOLOCK) ');
      strSql.Add('WHERE a.DiagnosisProjectID=' + QuotedStr(str[0]));
      for I := 1 to str.Count - 1 do
      begin
        strSql.Add('      OR a.DiagnosisProjectID=' + QuotedStr(str[I]));
      end;
      strSql.Add('ORDER BY a.DiagnosisProjectID');
      with QryTemp do
      begin
        Close;
        SQL.Text := strSql.Text;
        Open;
      end;
      //查询存在数据就添加数据到ListView
      if QryTemp.RecordCount > 0 then
      begin
        QryTemp.First;
        ListView1.Items.Clear;
        while not QryTemp.Eof do
        begin
          with ListView1.Items.Add do
          begin
            Caption := QryTemp.FieldByName('DiagnosisProjectID').AsString;
            SubItems.Add(QryTemp.FieldByName('DiagnosisProjectName').AsString);
          end;
          QryTemp.Next;
        end;
      end;
    finally
      str.Free;
      strSql.Free;
      QryTemp.Free;
    end;
  end;
end;

点击ListView点击行选中CheckBox

procedure TForm1.ListView1Click(Sender: TObject);
begin
  ListView1.Items[ListView1.Selected.Index].Checked := not ListView1.Items[ListView1.Selected.Index].Checked;
end;

ListView全选

procedure TForm1.btnSelectAllClick(Sender: TObject);
var
  I: Integer;
begin
  for I := 0 to ListView1.Items.Count - 1 do
  begin
    ListView1.Items[I].Checked := True;
  end;
end;

ListView取消选中

procedure TForm1.btnClearSelectClick(Sender: TObject);
var
  I: Integer;
begin
  for I := 0 to ListView1.Items.Count - 1 do
  begin
    ListView1.Items[I].Checked := False;
  end;
end;

ListView反选

procedure TForm1.btnUnSelectClick(Sender: TObject);
var
  I: Integer;
begin
  for I := 0 to ListView1.Items.Count - 1 do
  begin
    ListView1.Items[I].Checked := not ListView1.Items[I].Checked;
  end;
end;

查看ListView选中项

procedure TForm1.btnAllCheckedClick(Sender: TObject);
var
  i: Integer;
  s: string;
begin
  Memo1.Clear;
  for i := 0 to ListView1.Items.Count - 1 do
  begin
    if ListView1.Items[i].Checked then
    begin
      s := s + ListView1.Items[i].Caption + ':' + ListView1.Items[i].SubItems[0] + #13#10;
    end;
  end;
  Memo1.Text := s;
end;

 TreeView ListView操作联动示例代码



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