delphi - 如何从数据集中一次删除两个同名项目？

Question

我在Twwgrid中有一个列表，如下所示：


我希望使用如上所示的右键单击弹出菜单立即删除相同的库存（例如，删除两个均为CTN或UNIT的OREO_CHOC_CREAM）。但是现在我只能用下面的代码一一删除，有什么办法解决这个问题吗？

procedure Tfrm1.mniDeleteClick(Sender: TObject);
begin
  inherited;
    with grdItems.DataSource.DataSet do begin
      if (RecordCount <> 0) and (MessageBox( Application.Handle, 'Delete Record ?', 'Confirmation', MB_YESNO + MB_ICONQUESTION + MB_DEFBUTTON2 + MB_APPLMODAL) = IDYES) then
         Delete;
    end;
end;

Answer 1

我假设数据集是按库存＃排序的，否则将无法正常工作。

procedure Tfrm1.DeleteByStockNum();
var
  StockN: string;
  DataSet: TDataSet;
begin
  DataSet := grdItems.DataSource.DataSet;
  DataSet.DisableControls;
  try
    StockN := DataSet.Fields[0].AsString;
    //locating the very first record with this stock #
    while (not DataSet.BOF) and
          (DataSet.Fields[0].AsString = StockN) do
      DataSet.Previous;
    if DataSet.Fields[0].AsString <> StockN then
      //we are one record above
      DataSet.Next;
    //lets delete all the matching records
    while (not DataSet.IsEmpty)
           and (DataSet.Fields[0].AsString = StockN) do
      DataSet.Delete;
  finally
    DataSet.EnableControls;
  end;
end;


procedure Tfrm1.mniDeleteClick(Sender: TObject);
begin
  inherited;
    with grdItems.DataSource.DataSet do begin
      if (RecordCount <> 0) and (MessageBox( Application.Handle, 'Delete Record ?', 'Confirmation', MB_YESNO + MB_ICONQUESTION + MB_DEFBUTTON2 + MB_APPLMODAL) = IDYES) then
         DeleteByStockNum;
    end;
end;

请享用。 :)