Fill handle
View sourceDrag the fill handle (the small square at the bottom-right of the active range) to extend values across rows or columns. bc-grid detects arithmetic sequences, date series, weekday / month patterns, and otherwise repeats the source values.
Try this
The fill handle is the small square at the bottom-right corner of the active range.
- Click an Amount cell with value 1000. Drag the fill handle down 5 rows — value repeats.
- Click two Amount cells with values 1000 and 1100, drag the fill handle down — bc-grid detects the +100 step and continues 1200, 1300, 1400…
- Click a date cell with 2026-04-01. Drag down 6 — bc-grid increments by one day.
- Two cells with 2026-04-01 and 2026-05-01, drag — month-stride series.
- For text columns, the fill handle simply repeats the source values.
Series detection
- Numeric arithmetic. Two or more numbers with a constant delta — bc-grid extrapolates. Mixed signs / non-arithmetic falls back to literal repeat.
- Date series. Day, weekday, week, month, quarter, year. Detection is greedy on the shortest matching stride.
- Literal repeat. When no series is detected (single source cell, mixed types, validation rejection), the fill handle repeats the source rectangle as-is. Excel-compatible.
- Through the column pipeline. Filled cells go through
column.validate— a fill that would produce an invalid value rolls that cell back and surfaces the error. - Source = "fill".
onCellEditCommitfires for each filled cell withsource: "fill".
API
The fill handle ships on by default whenever the active range is editable. Hide it with rangeSelectionOptions={ fillHandle: false }. The detection layer is @bc-grid/core/range — extensible per the range RFC, but most consumers never need to touch it.