ReoGrid v4 Release Notes

v4.3.0

Renamed IsValidAddress to IsValidAddressFormat for clearer naming.
Added Worksheet.IsValidAddress for more strict address string validation.
Added IsValidCellAddress and IsValidRangeAddress to safely generate coordinate objects while validating address validity, with improved performance.
Enhanced robustness by utilizing IsValidCellAddress / IsValidRangeAddress in ReoGrid internal processing.
Fixed issue where cells were not loaded correctly when zooming during Lazy Loading.
Enhanced ADDRESS function to dynamically generate addresses from referenced cell values.
Enhanced INDIRECT function for more accurate cell reference management and proper interpretation of lowercase addresses.
Fixed issue where row number text was not scaled during zoom operations.
Fixed issue where Excel files containing certain RichFormatText became corrupted when loaded and saved.

Changed target framework from net8.0-windows7.0 to net8.0-windows.
Supports more general .NET 8 Windows environments.

Improved recalculation after worksheet cloning
- Resolved cases where calculation results became inconsistent or outdated immediately after cloning sheets containing shared formulas and dependency chains.
- Reorganized reference remapping and recalculation order during clone generation to ensure immediately consistent display.
- In most cases, additional Recalculate calls on the existing code side are no longer necessary. Explicit recalculation is still possible as before when needed.
Improved reliability of Border Excel output
- Fixed output to avoid writing empty/transparent borders as unnecessary “thin” styles.
- Fixed mapping of Dotted / DashDot / DashDotDot / medium* styles to prevent corruption on re-import.
- Resolved issue where unnecessary opposite lines appeared in corner cells when “outside only” setting was applied.

If you were using inner lines that were unintentionally added after setting “outside only” in previous versions, you will need to explicitly set them again.
Code that called Recalculate immediately after cloning may become redundant (can be kept for performance tuning purposes).

Enhanced Excel compatibility
- Now interprets 0 as FALSE.
- In IF functions and similar, 0 evaluates as FALSE and non-zero numbers evaluate as TRUE.
Implemented lookup functions
- VLOOKUP: Supports exact/approximate match for numeric and string keys. 4th argument interprets 1/0 in addition to TRUE/FALSE.
- HLOOKUP: Supports horizontal search.
- MATCH / XMATCH: Functions that return search positions. Supports direction specification (0, 1, -1).
- XLOOKUP: Enables flexible search. Supports if_not_found, match mode, and search mode.
Operator improvements
- Multiplication operator (*) can now convert numeric strings to numbers for calculation (e.g., "10"*2 → 20).
Error handling improvements
- Division by zero now returns InvalidValue (Excel-compatible #DIV/0!).
- Fixed FormulaStatus to be InvalidValue instead of Normal.

When using approximate matching, data must be sorted in ascending or descending order, as in Excel.

For an introduction to V4 new features, see What’s New in V4