v6.15.0

Added

• A Style object can be created directly from an options array – new Style($options)
• New method Excel::getSharedStringsRefCount()

Fixed

• Reused DataValidation/Conditional objects – applying one object to several ranges kept only the last range (#137)
• Sheet::setStateVeryHidden() made the sheet visible instead of very hidden
• Sheet::writeCell() rejected the last valid row (1048576) and column (XFD)
• Excel::rangeDimensionRelative() collapsed a range given as two associative points to a single cell
• A cell value containing invalid UTF-8 was silently dropped (xmlSpecialChars() now uses ENT_SUBSTITUTE)
• Numbers/dates under a comma LC_NUMERIC locale (e.g. de_DE) on PHP 7.4 produced invalid <v>3,14</v>
• Style corruption when two workbooks are open in the same process (StyleManager read default-font state from the wrong instance)
• Duplicate sheet names, and reuse of sheetN.xml after removeSheet() + makeSheet()
• Missing XML escaping of image names, chart names and hyperlink targets/locations
• Sheet::writeCells() dropped positional (integer-keyed) cell styles
• Formulas with escaped quotes "" and national function names containing regex metacharacters
• Shared strings lost leading/trailing spaces (xml:space="preserve")
• Area::getOffsetAddress() ignored its offset argument
• Sheet::skipRow(null) skipped no rows
• PHP 8.1+ deprecations from strtolower()/htmlspecialchars() on non-string arguments
• ZipArchive handle was not closed if saving threw an exception

Security

• Excel::download() strips CR/LF and quotes from the file name (header injection), sends the correct xlsx MIME type, adds an RFC 5987 filename* and checks headers_sent()
• Excel::loadImageFile() rejects dangerous stream wrappers (php://, phar://, glob://, zip://, data://, expect://, …)

Optimized

• Formula conversion skips the heavy _xlfn/_xlws passes when the formula contains no (
• sharedStrings.xml is streamed to disk instead of built entirely in memory (much lower peak memory when shared_string is enabled)
• Sheet::writeRow() hot path

Changed

• After removeSheet() + makeSheet(), new worksheet files use a monotonic index and never reuse a previous sheetN.xml