Merging cells

Combine multiple cells into one visual cell — useful for row banners, spanning headers, and decorative blocks. The merge is fully reversible.

Overview

Merge a rectangular range with MergeCells(AColumn, ARow, AColumnCount, ARowCount). The top-left cell of the range becomes the merge anchor — its value and layout drive the merged display. The other cells in the range are hidden but preserved; splitting restores them.

Method	Use it for
`Grid.MergeCells(AColumn, ARow, AColumnCount, ARowCount)`	Merge an explicit rectangle.
`Grid.MergeRange(ARange)`	Merge whatever range is currently selected.
`Grid.SplitCell(ACell)`	Reverse a merge by its coordinate.

DataGrid with the Q1-Q3 cells of one row merged into a single spanning cell

DataGrid with a merged cell range spanning three columns (dark theme)

Quick example

Merge a rectangular range of cells, then split it backPascalC++

procedure TForm1.FormCreate(Sender: TObject);
begin
  Grid.LoadFromCSVData('CARS.csv');
  Grid.Options.Selection.Mode := gsmCellRange;

  // Arguments are (AColumn, ARow, AColumnCount, ARowCount): the top-left anchor
  // plus the span. Merge a 3-column x 1-row banner starting at column 1, row 3.
  Grid.MergeCells(1, 3, 3, 1);

  // Merge a 2-column x 4-row block starting at column 7, row 2.
  Grid.MergeCells(7, 2, 2, 4);
end;

procedure TForm1.MergeSelectionClick(Sender: TObject);
begin
  Grid.MergeRange(Grid.Selection);
end;

procedure TForm1.SplitButtonClick(Sender: TObject);
begin
  Grid.SplitCell(Grid.Selection.StartCell);
end;

void __fastcall TForm1::FormCreate(TObject *Sender)
{
  Grid->LoadFromCSVData("CARS.csv");
  Grid->Options->Selection->Mode = gsmCellRange;

  // Arguments are (AColumn, ARow, AColumnCount, ARowCount): the top-left anchor
  // plus the span. Merge a 3-column x 1-row banner starting at column 1, row 3.
  Grid->MergeCells(1, 3, 3, 1);

  // Merge a 2-column x 4-row block starting at column 7, row 2.
  Grid->MergeCells(7, 2, 2, 4);
}

void __fastcall TForm1::MergeSelectionClick(TObject *Sender)
{
  Grid->MergeRange(Grid->Selection);
}

void __fastcall TForm1::SplitButtonClick(TObject *Sender)
{
  Grid->SplitCell(Grid->Selection.StartCell);
}

Step by step

Merge programmatically

Inline example 1PascalC++

// Merge starting at column 7, row 2, spanning 4 columns and 3 rows
Grid.MergeCells(7, 2, 4, 3);

// Merge starting at column 7, row 2, spanning 4 columns and 3 rows
Grid->MergeCells(7, 2, 4, 3);

Arguments are (AColumn, ARow, AColumnCount, ARowCount) — top-left anchor plus span extents.

Merge the user's selection

Inline example 2PascalC++

Grid.Options.Selection.Mode := gsmCellRange;

procedure TForm1.MergeButtonClick(Sender: TObject);
begin
  Grid.MergeRange(Grid.Selection);
end;

Grid->Options->Selection->Mode = gsmCellRange;

void __fastcall TForm1::MergeButtonClick(TObject *Sender)
{
  Grid->MergeRange(Grid->Selection);
}

Enable a keyboard merge shortcut

Inline example 3PascalC++

Grid.Options.Keyboard.CellMergeShortcut := True;

Grid->Options->Keyboard->CellMergeShortcut = true;

With this on, pressing the configured shortcut key merges the current selection range directly.

Split a merged region

Inline example 4PascalC++

procedure TForm1.SplitButtonClick(Sender: TObject);
begin
  Grid.SplitCell(Grid.Selection.StartCell);
end;

void __fastcall TForm1::SplitButtonClick(TObject *Sender)
{
  Grid->SplitCell(Grid->Selection->StartCell);
}

SplitCell accepts any coordinate that lies inside the merged region.

Check if a cell is part of a merge

Inline example 5PascalC++

if Grid.MergedColumns[AColumn] or Grid.MergedRows[ARow] then
  ShowMessage('Inside a merged region');

if (Grid->MergedColumns[AColumn] or Grid->MergedRows[ARow])
  ShowMessage(L"Inside a merged region");

Inspect a cell's merge extent

MergeInfo[AColumn, ARow] returns a TTMSFNCDataGridCellMergeInfo record for the anchor cell. The record carries ColumnOffset, RowOffset, ColumnSpan, and RowSpan:

Inline example 6PascalC++

var Info := Grid.MergeInfo[Col, Row];
if Info.ColumnSpan > 1 then
  ShowMessage(Format('Spans %d columns', [Info.ColumnSpan]));

var Info = Grid->MergeInfo[Col][Row];
if (Info->ColumnSpan > 1)
  ShowMessage(Format(L"Spans %d columns", [Info->ColumnSpan]));

Caveats

Merging across fixed rows/columns is supported but visually unusual.
A merged region acts as one cell for selection, focus, and keyboard navigation — Tab moves to the next cell after the merge.
Sorting a column that contains merges splits those merges first; the data underneath is preserved.
The grid's Options.Grouping.MergeHeader option merges group header cells automatically when grouping is active.

Combining merging and keyboard shortcuts

Merged cells are most convenient when users can create and undo them without code. Selection mode decides which ranges can be merged, the keyboard shortcut turns the selection into a merge, and programmatic calls prepare fixed banners up front. Combine them for grids with report-style headers where users adjust layout themselves. The example below creates a banner merge on load, sets range selection with the merge shortcut enabled, and provides buttons that merge or split the current selection. Remember that sorting splits merges first, so apply merges after sorting when the layout must be preserved.

Combining merging and keyboard shortcutsPascalC++

procedure TForm1.FormCreate(Sender: TObject);
begin
  Grid.LoadFromCSVData('CARS.csv');

  // Let users select ranges and merge them from the keyboard
  Grid.Options.Selection.Mode := gsmCellRange;
  Grid.Options.Keyboard.CellMergeShortcut := True;

  // Fixed banner: 3 columns x 1 row starting at column 1, row 3
  Grid.MergeCells(1, 3, 3, 1);
end;

procedure TForm1.MergeSelectionButtonClick(Sender: TObject);
begin
  Grid.MergeRange(Grid.Selection);
end;

procedure TForm1.SplitButtonClick(Sender: TObject);
begin
  Grid.SplitCell(Grid.Selection.StartCell);
end;

void __fastcall TForm1::FormCreate(TObject *Sender)
{
  Grid->LoadFromCSVData("CARS.csv");

  // Let users select ranges and merge them from the keyboard
  Grid->Options->Selection->Mode = gsmCellRange;
  Grid->Options->Keyboard->CellMergeShortcut = true;

  // Fixed banner: 3 columns x 1 row starting at column 1, row 3
  Grid->MergeCells(1, 3, 3, 1);
}

void __fastcall TForm1::MergeSelectionButtonClick(TObject *Sender)
{
  Grid->MergeRange(Grid->Selection);
}

void __fastcall TForm1::SplitButtonClick(TObject *Sender)
{
  Grid->SplitCell(Grid->Selection.StartCell);
}

Grid.MergeCells(AColumn, ARow, AColumnCount, ARowCount)
Grid.MergeRange(ARange)
Grid.SplitCell(ACell)
Grid.MergedColumns[col], Grid.MergedRows[row] — quick "in a merge" lookup
Grid.MergeInfo[AColumn, ARow] — TTMSFNCDataGridCellMergeInfo with ColumnOffset, RowOffset, ColumnSpan, RowSpan
Grid.Options.Keyboard.CellMergeShortcut
Grid.Options.Grouping.MergeHeader / MergeDelimiter