DBGRID中如何动态统计并所选记录的汇总数值？？？

Question

OnMouseUp()
  if gShow.SelectedRows.Count<>m_nLastCnt then
    Calc();
  m_nLastCnt := gShow.SelectedRows.Count;

Answer 1

楼上的方法是行不通的，多选时可能只用keyboard根本未触发MouseUp,而且即使用Mouse+Ctrl在选不同的记录时，只要所选择的记录数相同，也不会触发的,不过还是谢谢！

Answer 2

你先试试。肯能有缺陷。DBGRID1设为多选。procedure TForm1.DBGrid1CellClick(Column: TColumn);
var i:integer;
s:real;
b:tbookstr;
begin
      s:=0;
      b:=query1.book;
      query1.disableControls;
      query1.First;
      for i:=1 to query1.RecordCount do
      begin
           if dbgrid1.SelectedRows.CurrentRowSelected then
           s:=query1.fieldbyname('Length (cm)').asfloat+s;
           query1.Next;
      end;
      edit1.Text:=floattostr(s);
      query1.EnableControls;
      query1.book:=b;
end;

Answer 3

procedure TForm1.DBGrid1CellClick(Column: TColumn);
var i:integer;
s:real;
b:tbookstr;
begin
      s:=0;
      b:=query1.book;
      query1.disableControls;
      for I := 0 to DBGrid1.SelectedRows.Count - 1 do 
      begin
          query1.Book := DBGrid1.SelectedRows.items[I];
          s:=query1.fieldbyname('Length (cm)').asfloat+s;
      end;
      edit1.Text:=floattostr(s);
      query1.EnableControls;
      query1.book:=b;
end;