Layout

Column widths, row heights, merged regions, freeze panes, hidden rows/columns, and active cell position.

Column Width

sheet.setColumnWidth(0, 24 * 256);  // column A = 24 characters wide

Width is in units of 1/256th of a character width. Multiply by 256 for convenience.

To read back the width of a column:

int width = sheet.getColumnWidth(0);  // returns width in 1/256th character units

Row Height

row.setHeight(30);  // 30 points

Height is in points (1/72 inch). The default row height is 15.0 points.

To read back the height of a row:

float height = row.getHeight();  // returns height in points

Merged Regions

using DotnetPoi.SS.Util;

sheet.addMergedRegion(new CellRangeAddress(0, 0, 0, 3));
// Merges cells A1:D1 (row 0, columns 0-3)

CellRangeAddress constructor: (firstRow, lastRow, firstCol, lastCol).

Freeze Panes

sheet.createFreezePane(0, 3);
// Freezes the first 3 rows (header area) — scrollable below row 3

sheet.createFreezePane(2, 0);
// Freezes the first 2 columns — scrollable to the right

Parameters: (colSplit, rowSplit). The split is 0-indexed; rows above and columns left of the split stay visible.

Hidden Rows and Columns

sheet.getRow(2).setZeroHeight(true);  // hide row 3

sheet.setColumnHidden(1, true);       // hide column B
sheet.isColumnHidden(1);              // check if hidden

Hidden rows/columns are preserved on round-trip.

Active Cell and Sheet Selection

In Japanese spreadsheet workflows, setting the active cell position and selecting the active sheet is particularly important for user navigation when the file is opened.

Set the Active Cell

sheet.setActiveCell("D5");  // cell D5 will be selected when opened

The active cell is the cell that has keyboard focus when the workbook is opened in Excel. The reference is specified as an Excel-style string (e.g. "A1", "C10", "AB42").

To read back the active cell:

string? activeCell = sheet.getActiveCell();  // returns "D5", or null if not set

Set the Active Sheet

wb.setActiveSheet(1);   // the second sheet (0-indexed) becomes the active tab
wb.setSelectedTab(1);   // alias — selects the tab

To read back which sheet is active:

int activeSheet = wb.getActiveSheetIndex();  // returns 0, 1, 2, ...

Select a Sheet

When a workbook has multiple sheets, you can mark a sheet as selected (shown in the tab bar):

sheet.setSelected(true);   // mark this sheet as selected
bool selected = sheet.isSelected();  // check if selected

Notes

• setActiveSheet() and getActiveSheetIndex() are serialized to XML and round-trip correctly.
• setActiveCell() and sheet.setSelected() are available in the API but are currently in-memory only — they are not yet written to or read from the underlying XML. A future update will add XML serialization for the <selection> element and activeCell attribute in <sheetViews>.

See examples/UsageSamples/Program.cs (CreateSpreadsheet) and examples/Phase3InterfaceExample/:

examples/UsageSamples

examples/Phase3InterfaceExample