在AdoQuery 怎样动态创建Calculated 字段(既计算字段)

Question

谢谢~~同上

Answer 1

procedure AddCalcField(FdName: string; DSName: TDataSet; dt: TFieldClass);
begin
  if DSName.FindField(FdName) <> nil then
    exit;
  DSName.Close;
  try
    with dt.Create(DSName) do
    begin
      FieldName := FdName;
      DisplayLabel := FdName;
      FieldKind := fkCalculated;      
      Name := DSName.Name + 'DSDesigner' + inttostr(DsName.FieldCount);
      index := DSName.FieldCount;
      DataSet := DSName;
      DSName.FieldDefs.Update;
    end;
  except
    on e: exception do
      raise Exception.Create(E.Message);
  end;
end;