Caption := sgShopList.Rows[sgShopList.RowCount +].CommaText;
Caption := sgShopList.Rows[sgShopList.RowCount -1000].CommaText;
Rows[]的索引值，可以超过 RowCount，但是不能 小于0
Cells[]的索性值，读取时可以任意，包括-1 或者10000，不会报错。
with TStringGrid.Create(Self )do
try
Parent := Self;
ShowMessage( Cells[-, ] );
finally
free
end;
function TStringGrid.GetCells(ACol, ARow: Integer): string;
var
ssl: TStringSparseList;
begin
ssl := TStringSparseList(TSparseList(FData)[ARow]);
if ssl = nil then Result := '' else Result := ssl[ACol];
end;
写入时，不能是 -1，但可以是 100000等
with TStringGrid.Create(Self )do
try
Parent := Self;
Cells[, ] := '';
ShowMessage( Cells[, ] );
finally
free
end;
function TSparseList.Get(Index: Integer): Pointer;
begin
if Index < then TList.Error(SListIndexError, Index);
Result := FList[Index]
end;
property Row: Longint read FCurrent.Y write SetRow;
procedure TCustomGrid.SetRow(Value: Longint);
begin
if Row <> Value then FocusCell(Col, Value, True);
end;
procedure TCustomGrid.FocusCell(ACol, ARow: Longint; MoveAnchor: Boolean);
begin
MoveCurrent(ACol, ARow, MoveAnchor, True);
UpdateEdit;
Click;
end;
procedure TCustomGrid.MoveCurrent(ACol, ARow: Longint; MoveAnchor,
Show: Boolean);
var
OldSel: TGridRect;
OldCurrent: TGridCoord;
begin
if (ACol < ) or (ARow < ) or (ACol >= ColCount) or (ARow >= RowCount) then
InvalidOp(SIndexOutOfRange);
if SelectCell(ACol, ARow) then
begin
OldSel := Selection;
OldCurrent := FCurrent;
FCurrent.X := ACol;
FCurrent.Y := ARow;
if not (goAlwaysShowEditor in Options) then HideEditor;
if MoveAnchor or not (goRangeSelect in Options) then
begin
FAnchor := FCurrent;
if goRowSelect in Options then FAnchor.X := ColCount - ;
end;
if goRowSelect in Options then FCurrent.X := FixedCols;
if Show then ClampInView(FCurrent);
SelectionMoved(OldSel);
with OldCurrent do InvalidateCell(X, Y);
with FCurrent do InvalidateCell(ACol, ARow);
end;
end;