AGGREGATE Options and Nested Gates in HotXLS for Delphi
How HotXLS decodes the AGGREGATE options matrix in Delphi and keeps the ignore-hidden and nested-SUBTOTAL gates from leaking into precedent formulas
Software Development Blog
HotXLS Delphi Component
HotXLS Delphi Component tutorials for generating and reading Excel spreadsheets in Delphi
Detect Tampered XLSX: HotXLS Agile dataIntegrity HMAC
Verify Agile-encrypted XLSX packages in Delphi with HotXLS: HMAC-SHA-512 dataIntegrity, constant-time verifier checks and the classic write reservation records
Read Agile-Encrypted Excel Files in Delphi with HotXLS
How HotXLS reads Agile-encrypted XLSX in Delphi: OpenEncrypted parses EncryptionInfo, runs SHA-512 spin-count key derivation, then decrypts AES-CBC segments
Partitioning Anchored Conditional Formats in HotXLS
How HotXLS splits conditional formatting and data validation rules into prioritised rule objects when row or column edits divide their range in Delphi
HotXLS Array Formulas: Why Excel Adds @ and #VALUE!
HotXLS stores array-operator formulas like SUM(A1:B1*{10,100}) as Excel 365 dynamic arrays in XLSX and XLS from Delphi, so Excel stops inserting @ and #VALUE!
Run Excel AutoFilters Without Excel in Delphi: HotXLS
HotXLS evaluates saved Excel AutoFilters in Delphi: value lists, date groups, Top 10, dynamic dates, colour and icon filters, with a frozen date and hard limits
BIFF Record Length Drift in a Delphi XLS Writer
A HotXLS pivot emitter declared a 24-byte BIFF body and wrote 26, so chart sheets vanished on reopen. The fix, and how to find that drift yourself
BIFF SupBook and XTI External Link Classification in Delphi
How HotXLS classifies BIFF SupBook and XTI records in Delphi, why same-sheet, add-in and DDE or OLE links cannot be guessed from a self flag or empty URL
HotXLS XLS XOR Obfuscation: Key Derivation and XorRor
How HotXLS writes Excel 5.0/95 XOR-protected XLS files that Excel 16 opens: CreateXorKey_Method1 key, XorRor array, XorArrayIndex and Delphi code
Reading Excel 2.0 to 4.0 Files in Delphi with HotXLS
HotXLS opens pre-OLE Excel 2.0, 3.0 and 4.0 workbooks from Delphi, reading raw BIFF streams, per-generation cell records and cached formula results
BIFF8 56-Colour Palette: OKLab Colour Mapping in HotXLS
How HotXLS maps RGB and theme colours onto the 56-slot BIFF8 palette with deterministic OKLab matching, read-only palette plans and an opt-in XLS save policy
BIFF8 AutoFilter DOPER Criteria in Delphi with HotXLS
Why a BIFF8 AutoFilter saved as a string DOPER matches no numeric cells in Excel, and how HotXLS writes number, Boolean and AND/OR criteria in Delphi XLS files
BIFF8 Chart Secondary Axis Groups in Delphi with HotXLS
How HotXLS writes BIFF8 secondary axis groups in Delphi: AXESUSED, two AxisParent blocks, and why the chart group lives inside each axis group
Embedding Chart Objects on Worksheets with HotXLS
HotXLS anchors a BIFF8 chart substream to a worksheet as an OBJ type-5 host control, so the chart sits beside the data instead of occupying its own sheet
BIFF8 Font Index Skips 4: HotXLS Rich Text Runs in Delphi
Why BIFF8 font indexes never use 4, and how HotXLS keeps XF records, rich text strings, comment and text box runs bound to the right FONT record in Delphi
Writing BIFF8 PivotTables in Delphi: SXDB and SXLI
PivotTables are the most intricate structure in the .xls binary format. See how HotXLS builds a self-contained pivot cache and packs SXDBB records in Delphi
HotXLS BIFF8 Selection Records and Pane Scroll in Delphi
How HotXLS for Delphi writes BIFF8 Selection records in 1369-area chunks, maps pane codes explicitly, and splits pane scroll between Window2 and Pane
BIFF8 XLUnicodeString Decoding in Delphi: cch and fHigh
How HotXLS decodes BIFF8 XLUnicodeString payloads in Delphi: GetWideString counts bytes, fHigh 0 needs GetString, and a wrong pairing fails silently
Bond and Treasury Formulas in Delphi with HotXLS
HotXLS evaluates PRICE, YIELD, DURATION, coupon-date and treasury-bill functions from Delphi, with all five day-count bases and no Excel installed
Replaying Untrusted EMF and WMF Safely in HotXLS
HotXLS decodes worksheet metafile pictures into a bounded command scene instead of handing the bytes to GDI playback, with budgets and fail-closed parsing
Read Excel Cached Formula Values in Delphi Without Recalc
HotXLS reads Excel formula cached values in Delphi without triggering recalculation, keeping ETL runs fast and source workbooks byte for byte unchanged
Excel Camera Objects from Delphi: Live Snapshots
HotXLS creates Excel camera objects from Delphi, placing a live picture of a cell range that Excel re-renders on load, with round-trip preservation of the link
Export an Excel Cell Range as One Image With HotXLS
TXLSCellImageExporter renders any XLS or XLSX cell rectangle to one PNG or JPEG with no pagination, explicit pixel and byte budgets and an atomic replace
Implementing the CF_HTML Clipboard Format in Delphi
Build a CF_HTML clipboard payload in Delphi with HotXLS so Excel ranges paste into Word or a browser with styling intact, using precise byte offsets
HotXLS Chart Date Axis: Calendar-Accurate Ticks in Delphi
How HotXLS renders Excel chart date axes in Delphi: workbook serials, month-end tick clamping, automatic day, month and year units, and exact dateAx round trips
HotXLS Chart Fingerprint Timing and Anchor Offsets in Delphi
HotXLS replays untouched Excel charts byte for byte from Delphi by resolving drawings via relationships, fingerprinting after parsing and keeping anchor offsets
HotXLS: Exact Excel Trendline Equation Labels in Delphi
Compute Excel trendline equation and R-squared label text in Delphi with HotXLS XLSTrendlineEquationLabel, matching DataLabel.Text for all six trendline types
Excel Waterfall and Treemap Charts in Delphi with HotXLS
Create Excel waterfall and treemap charts from Delphi with HotXLS: cx chartSpace parts, layoutId series types, cx pt caches and the AlternateContent anchor
HotXLS Charts and Images: Excel Drawings in Delphi
How to add Excel charts, images, and shapes from Delphi with HotXLS: chart sheets in XLS, embedded charts and pictures in XLSX, EMU sizing, and anchor traps
Excel Column Width and Max Digit Width (MDW) in Delphi
Excel column width is measured in Max Digit Width units, so a non-Calibri Normal font shifts every column boundary. How HotXLS measures MDW in Delphi
Excel Comments and Hyperlinks in Delphi with HotXLS
Write cell comments with authors, external URLs, and in-workbook links from Delphi using HotXLS, including the XLSX internal-link API and XLS comment quirks
Read OLE2 Compound Files in Delphi Without COM IStorage
HotXLS parses Compound File Binary v3 containers in pure Pascal: header signature, in-header DIFAT, FAT chains, MiniFAT and the directory tree, no ole32.dll
Excel Conditional Format Evaluation in Delphi with HotXLS
How HotXLS evaluates Excel conditional formatting rules in Delphi outside Excel, and the Top 10 percent, above average and duplicate cases Excel 16 tests pinned
HotXLS Conditional Formatting and Rich Text in Delphi
Apply cellIs rules, data bars, icon sets, and rich text runs from Delphi with HotXLS, avoiding the dxf style and font pool index traps in XLSX files
Delphi Constructor Exceptions and Nil-Safe Destructors
When a Delphi constructor raises, the RTL calls Destroy on a half-built object. See how nil-safe destructors in HotXLS keep EOutOfMemory intact
HotXLS Crash-Safe Saves: Staged Temp Files in Delphi
HotXLS saves XLSX, ODS, and XLS in Delphi through a staged temp file and an atomic Windows rename, so an interrupted save cannot corrupt the workbook
Delphi Cross-Compiler Build Matrix: HotXLS Since XE5
Five compiler rejections that fire only on Delphi XE5, and why a build script exercising just the newest compiler let the HotXLS build matrix rot in silence
HotXLS Cross-Workbook Copy and Formula Rebinding in Delphi
Copied Delphi worksheets can total the wrong sheet or turn formulas into links and values. HotXLS AddCopy rebinds formulas, charts and fonts by name and value
Live Cross-Workbook Formulas in Delphi with HotXLS
HotXLS evaluates formulas referencing another workbook against a live in-memory object in Delphi, falling back to the external-link cache when unregistered
Export Excel to CSV, TSV, and HTML in Delphi (HotXLS)
Export Excel sheets to CSV, TSV, and HTML from Delphi with HotXLS. Covers RFC 4180 quoting, UTF-8 BOM, and why formulas need Calculate before export
A Custom Spreadsheet Grid in Delphi with HotXLS
HotXLS TXLSWorkbookViewer renders Excel workbooks as a Delphi grid: merged-cell hit testing, scroll sync, cell selection, and hyperlink and comment events
HotXLS Data Validation, AutoFilter and Tables in Delphi
Add dropdown validation, AutoFilter criteria, and Excel tables from Delphi with HotXLS, including server-side filter preview and the 0-based column ID trap
Exporting Delphi Datasets to Excel Reports with HotXLS
Export TDataset results to Excel from Delphi with HotXLS: TDataToXLS grouping and paging, the VCL dependency trap, XLSX conversion, and a service-safe loop
Excel Date Serials in Delphi: 1900 vs 1904 and numFmt
An Excel date is just a number until you know which epoch it counts from. See how the 1900 and 1904 systems differ by 1462 days and how numFmt flags a date
Auditing Excel Formula Caches with HotXLS Deep Recalc
HotXLS recalculates every formula in an isolated overlay and reports each cached value that disagrees, without writing to the workbook unless you ask for it
HotXLS Implicit Intersection for Defined Names in Delphi
Why a 4805-formula loan template raised a false circular reference in HotXLS, and how defined-name implicit intersection and soft lookup-scan edges fixed it
Defined Names and Cross-Sheet Formulas in Delphi (HotXLS)
Create workbook-scoped and sheet-scoped defined names with HotXLS in Delphi, write cross-sheet formulas that survive edits, and avoid _xlnm name conflicts
HotXLS Dependency Graph: Indexing Array Formula Outputs
How HotXLS replaced quadratic edge scans in its Delphi formula dependency graph with a max-row segment tree, cutting a 100,000-formula recalc from 18 s to 0.1 s
Excel Document Timestamps in Delphi: FILETIME, UTC and DST
Why HotXLS workbook created and saved dates drifted by a day or a time zone, and how FILETIME, MS-OLEPS property IDs and W3CDTF stamps map to UTC in Delphi
HotXLS Dropdown Lists and Input Validation in Delphi
Read Excel dropdown list items in Delphi with HotXLS, pick entries by index or text, and check typed input against data validation rules in XLS and XLSX
Dynamic Array Spill Formulas in Delphi with HotXLS
Evaluate Excel 365 dynamic array spill formulas from Delphi with HotXLS: XLOOKUP, FILTER, SORT, UNIQUE and SEQUENCE behaviour anchored by SetArrayFormula
Delphi Engineering Functions: Base Conversion, Complex Maths
Excel's DEC2BIN, HEX2DEC and IMSUM functions hide ten-bit two's complement and string-encoded complex maths. See how HotXLS implements them in Delphi
Comparison Chains, Blank Cells and SUMIF in HotXLS Delphi
Why HotXLS returns FALSE for chained comparisons as Excel does, how blank cells compare equal to 0 and empty text, and how SUMIF resizes a one-cell sum range
Why Excel Repairs a Valid XLSX: OPC Package Rules in Delphi
Why Excel shows the repair prompt on an XLSX other readers accept: a required phoneticPr fontId, one Override per part and unique root rIds in Delphi writers
HotXLS Text Comparison: Excel Word Sort Order in Delphi
How HotXLS compares text like Excel in Delphi: locale word sort, case-insensitive, hyphens only break ties, and why CompareText and ordinal sorts disagree
HotXLS Excel Wildcards: COUNTIF, MATCH, DSUM and Find
How HotXLS matches Excel wildcards in Delphi: COUNTIF reads a~b literally, MATCH treats ~ as an escape, DSUM matches prefixes and whole-cell Find backtracks
HotXLS File Monitor Callback Deadlock in Delphi
HotXLS fires TXLSFileMonitor events on the main thread while the worker waits, so stopping the monitor within OnFileChanged deadlocks without thread ownership
HotXLS Formula Engine and Custom Functions in Delphi
Evaluate Excel formulas in Delphi with HotXLS: the Calculate engine, OnUserFunction custom functions, array formulas, and why CSV export needs computed values
Trace Excel Formula Evaluation Step by Step in Delphi
Excel can evaluate a formula one step at a time. See how HotXLS reproduces that step-by-step reduction for auditing and debugging spreadsheets in Delphi
Formula References When Inserting Rows in HotXLS
How HotXLS shifts A1 formula references when you insert or delete rows and columns in Delphi: relative and absolute refs, range endpoints, and #REF! rules
HotXLS on Free Pascal: Unicode, COM Slots and zlib
Building HotXLS under Free Pascal needs DELPHIUNICODE, CORBA interfaces with explicit COM slots and a Pascal AES path in place of the Delphi OMF objects
Excel Chart Theme Colours in Delphi: HotXLS GelFrame
How HotXLS writes theme-coloured chart fills into binary XLS: the GelFrame record, the OfficeArt scheme index in the red byte, and the MSOTINT payload
HotXLS Image Geometry in Delphi: EMU, cm, and Scaling
Size embedded XLSX images by physical dimensions in Delphi with HotXLS: EMU units explained, centimetre and point geometry, aspect-locked scaling, cm margins
Reading GIF, BMP and JPEG Header Geometry in HotXLS
HotXLS reads true pixel dimensions from GIF, BMP and JPEG headers so AddPicture writes real geometry rather than a 100x100 fallback that stretches images
Incremental Formula Recalculation in HotXLS for Delphi
HotXLS Workbook.Recalculate builds a formula dependency graph in Delphi to re-evaluate only dirty cells: volatile functions, topological order, cycle handling
Patch One Worksheet in a Large XLSX from Delphi
HotXLS rewrites one worksheet inside an existing XLSX package from Delphi while every untouched part crosses over with its compressed bytes verbatim
Iterative Calculation for Circular References in Delphi
Resolve intentional circular references in Delphi with HotXLS: iterative calculation via Iterate, IterateCount and IterateDelta, and how the cycle converges
LAMBDA and LET in Delphi: HotXLS Formula Closures
Evaluate Excel LAMBDA closures and complete LET semantics in Delphi with HotXLS: named lambdas, lexical capture, shadowing rules and comma separators
Large Excel Workbook Performance in Delphi with HotXLS
Practical HotXLS performance tuning for large Excel files in Delphi: StreamingWrite saves, style pool reuse, row callbacks, and faster read-only loads
HotXLS List Validation: 255-Char Limit and x14 Extensions
Why Excel refuses XLSX list validations longer than 255 characters, how XLSB and x14 extensions differ, and how HotXLS for Delphi handles each format
HotXLS Lookup Scans and False Circular References
Why VLOOKUP over a column containing the formula itself is legal in Excel, and how HotXLS separates scan edges from ordering edges to stop false cycles
Lossless XLSX Round-Trip in Delphi: Theme, extLst, calcChain
How HotXLS preserves custom themes, unknown extLst blocks, and calcChain when Delphi code edits one cell in an XLSX file, and where round-trip fidelity ends
HotXLS Merged Cells and Report Template Layout in Delphi
How HotXLS handles merged cells in Delphi report templates: anchor-cell semantics, InsertRows shifting rules, merge audits, and HTML and RTF export behaviour
Metadata-Only and Selective XLSX Loading with HotXLS
Open a large XLSX in Delphi without parsing every sheet: HotXLS MetadataOnly discovery, SelectedSheets loading, on-demand LoadSheet and raw-part saves
ODS Pivot Table Round-Trip in Delphi: XML Namespace Scope
How HotXLS keeps ODS data pilot tables through a Delphi open and save cycle by replaying the XML subtree verbatim, and why ancestor xmlns bindings ride along
HotXLS ODS Interop: Formulas and Rules Excel Can Read
How HotXLS writes ODS files from Delphi that Excel 16 and LibreOffice both read: OpenFormula references, declared namespaces and dual conditional format markup
Open and Save ODS Files in Delphi with HotXLS
HotXLS opens and saves OpenDocument Spreadsheet files from Delphi: SaveAsODS export options, what the ODS import path reads back, and what survives a round trip
ODS Repeated Rows as Row-Height Runs in HotXLS for Delphi
A million repeated ODS rows in Delphi: HotXLS keeps row heights as runs, inherited blank-cell styles as range overlays, and writes repeat counts back on save
Why Excel Rejects Your Encrypted Workbook: ECB and RC4
Two encryption traps where the password is right but Excel reports corruption. See how an ECB versus CBC mix-up and an RC4 re-key drift break interop in Delphi
Generate Excel Files in Delphi Without Office Automation
Build XLS and XLSX workbooks from Delphi services without installing Excel: native BIFF and OOXML writers, stream output to HTTP responses, COM-free
Verify and Re-sign Excel Digital Signatures in Delphi
HotXLS verifies XLSX package signatures in Delphi without Excel: XML-DSig digests, C14N, relationship selectors, WinCrypt trust policy and safe re-signing
Parallel XLSX Parsing in Delphi: Memory Manager Bottleneck
Why adding threads made XLSX parsing slower in Delphi, and how HotXLS cut heap allocations from 20 to 9.1 per cell to reach a 1.90x parallel speedup
Export Excel Workbooks to PDF/A from Delphi
HotXLS exports spreadsheets to archival PDF/A from Delphi with an embedded sRGB output intent, pdfaid metadata and the font rules an archive validator checks
Framing BIFF PivotCache Records with HotXLS in Delphi
The BIFF PivotCache substream frames SXDB, SXDBB and SXFDB by body layout rather than record number, and HotXLS latches the dialect from the first record
Pivot Show Values As in Delphi: Rank and Running Total
Set Excel pivot Show Values As modes from Delphi with HotXLS: rank, running total, percent of parent, the x14 pivotShowAs extension and refresh-safe files
Sort Pivot Items by Value in Delphi: autoSortScope and -2
Sort Excel pivot items by a measure in Delphi with HotXLS: how autoSortScope stores the Values field as 4294967294, tie-breaking and collapsed members
Build and Refresh Excel Pivot Tables in Delphi with HotXLS
Build XLSX pivot tables in Delphi with HotXLS: AddPivotTable, calculated items and fields, showDataAs value displays, date grouping, and in-process refresh
HotXLS Precision as Displayed: Excel Rounding Rules
How Excel precision as displayed rounds stored values by format section, percent signs and scaling commas, and how HotXLS matches Excel 16 in Delphi
Editing Excel Charts Without Losing ChartML in HotXLS
HotXLS preserves the original ChartML of an imported Excel chart while you edit titles, series and axes in Delphi, and builds combination charts with two axes
HotXLS: Sheet Protection, Page Setup, and Printing in Delphi
Protect worksheets, keep input ranges editable, and control print layout in Delphi with HotXLS: Locked flags, page setup, scaling, and header codes
Pull Row Cursor for XLS, XLSX, ODS and CSV in Delphi
HotXLS unifies XLS, XLSX, ODS and CSV streaming reads behind one pull row cursor in Delphi: explicit state machine, idempotent Cancel and borrowed row views
R1C1 Formula Notation in Delphi with HotXLS
Compile R1C1 formulas in Delphi with HotXLS: GetCompiledFormulaR1C1 resolves R2C3, R[-1]C[2] and RC per cell, so one relative formula fills a column
REGEXTEST and REGEXEXTRACT in Delphi via Static PCRE2
HotXLS evaluates Excel 365 REGEXTEST, REGEXEXTRACT and REGEXREPLACE offline in Delphi with static UTF-16 PCRE2, array broadcasting and ReDoS step budgets
Row-Block Cell Storage and Streamed XLSX Saves in HotXLS
How HotXLS keeps large Delphi workbooks small in memory: 256-row cell blocks, interval style overlays that never materialise empty cells, and streamed saves
List Sheet Names Fast in Delphi with HotXLS GetSheetNames
Read worksheet names from XLS, XLSX, and ODS files in Delphi without loading cell data: HotXLS GetSheetNames, encrypted-file detection, intake triage
Excel Sparklines in Delphi: HotXLS and the x14 Extension
Create Excel sparklines in Delphi with HotXLS: line, column and win/loss groups, ARGB colour slots, and the x14 extLst block Excel 2010 and later render
Excel Statistical Functions in Delphi: NORM, CHISQ, BETA
Excel's NORM, CHISQ and BETA functions hide real numerical analysis. See how HotXLS computes them with regularised gamma and beta in Delphi, and one Log bug
Stream Huge XLSX Files in Delphi Without Loading Them
A million-row XLSX need not fit in memory. See how HotXLS scans worksheet parts with a no-DOM streaming reader at near-constant memory in Delphi
Write Million-Row XLSX in Delphi at Constant Memory
Generating a giant XLSX should not grow with row count. See how HotXLS streams OOXML with inline strings and no shared-string table in Delphi
HotXLS Streaming Writes for Delphi Server Batch Jobs
Keep large XLSX exports inside memory limits with HotXLS StreamingWrite, row-level write callbacks, style pool reuse, and per-thread batch workbook jobs
Writing ISO 29500 Strict XLSX Files from Delphi
HotXLS writes ISO/IEC 29500 Strict workbooks from Delphi, translating every package part to purl vocabularies and refusing the features Strict forbids
Structured Diagnostics Instead of Boolean Results in HotXLS
HotXLS replaces boolean Save and Open results with structured diagnostics: stable error codes, severity levels, and sheet context for Delphi apps
Excel Structured Table References in Delphi with HotXLS
Evaluate Table[Column] structured references in Delphi with HotXLS: item specifiers, column spans, verbatim round-trip and the unsupported current-row form
SUBTOTAL and AGGREGATE Hidden Rows in Delphi with HotXLS
How HotXLS makes SUBTOTAL 109 and AGGREGATE skip hidden and filtered rows in Delphi, with a row-hidden callback gate and a central arity check in the dispatcher
Excel Table Slicers in Delphi: HotXLS Round-Trip
A table slicer cache names its table by a bare tableId, so copied bytes break once tables renumber. HotXLS rebuilds it in Delphi and keeps rIds consistent
Tagged PDF Figures From Excel Images With HotXLS
How HotXLS turns worksheet pictures carrying alternative text into independent PDF Figure structure elements, and why one MCID allocator per page is mandatory
Template-Based Excel Report Generation in Delphi with HotXLS
Fill Excel report templates from Delphi with HotXLS: locate placeholders with FindText, clone detail rows, insert rows safely, and recalculate before saving
Threaded Comments in Excel Files with Delphi and HotXLS
Write Excel 365 threaded comments from Delphi with HotXLS: AddThreadedComment reply chains, the threadedComments and person parts, and legacy note differences
TrueType Font Subsetting via fontsub.dll in Delphi
HotXLS subsets embedded PDF fonts via the Windows fontsub.dll CreateFontPackage API, keeping only the glyphs a Delphi worksheet export actually used
Unicode-Safe Spreadsheet Export in Delphi: RTF and HTML
Non-ASCII text can collapse to question marks across RTF, HTML, CSV and ZIP exports. See how HotXLS keeps Unicode intact on every export path in Delphi
HotXLS Unsafe Formula Callbacks: Gating CALL and WEBSERVICE
HotXLS denies CALL, REGISTER.ID, WEBSERVICE, DDE and 16 other formula names before argument evaluation, so a preserved formula never runs Delphi host callbacks
HotXLS: Preserve VBA Macros and External Links in Delphi
How HotXLS preserves VBA projects and external links when Delphi code edits XLS and XLSX workbooks: macro-enabled saves, link targets, and round-trip limits
Rewriting VBA Source and Recompressing MS-OVBA in Delphi
HotXLS lets Delphi developers rewrite VBA module source code and recompress it with the MS-OVBA algorithm, then write the macros back into XLS or XLSM files
HotXLS: Workbook Audit and Format Conversion in Delphi
Audit unknown Excel files from Delphi with HotXLS: count charts, formulas, macros, and protection, then convert XLS, XLSX, and ODS with known fidelity limits
Diff Two Excel Workbooks in Delphi with HotXLS
HotXLS compares two workbooks from Delphi and reports sheet, cell, formula and merge differences as a structured list and a readable report, no Excel
Setting Excel Document Properties in Delphi with HotXLS
Set and read Excel document properties from Delphi with HotXLS: title, author, company, and keywords across BIFF SummaryInformation and OOXML docProps parts
HotXLS Read Leases and Write Guards for Delphi Workbooks
How HotXLS coordinates workbook reads and writes in Delphi using O(1) read leases, fail-fast write guards, reentrant transactions and a generation counter
Export Excel Worksheets to PDF in Delphi Without Office
HotXLS renders Excel worksheets to paginated PDF in Delphi and C++Builder with SaveAsPDF and no Office: fills, borders, fonts, embedded fonts for Unicode text
XLOOKUP and XMATCH Binary Search Modes in Delphi
How HotXLS evaluates XLOOKUP and XMATCH in Delphi: legal match and search modes, O(log n) binary descent, duplicate key edges, and why wildcards get rejected
Stop XLS Saves Silently Recalculating Formulas in Delphi
HotXLS saves classic XLS files cache first, writing loaded formula values instead of recalculating, and keeps the cached value of BIFF shared formula root cells
Reading and Writing XLSB Binary Workbooks in Delphi
How HotXLS opens and saves Excel XLSB binary workbooks from Delphi, what the validated subset covers, and why default fonts and built-in formats matter
Lossless XLSX Double Round-Trips in Delphi: 17 Digits
Why HotXLS writes XLSX numbers with 17 significant digits and corrects RTL parsing on read, so each Delphi double survives an Excel save and reopen bit for bit
Encrypt XLSX Files with AES in Delphi using HotXLS
Write AES-encrypted XLSX files from Delphi with HotXLS SaveAsEncrypted: ECMA-376 Standard Encryption, password handling, and the write-only decryption limit
Why Excel Ignores Cached #SPILL! and #CALC! Errors
How HotXLS saves #SPILL! and #CALC! caches Excel reads: lowercase rich value GUID, fileVersion 7, calcId 191029, the RD calc feature and t=str array text
XLSX OPC Relationship Resolution in Delphi Parsers
Why hardcoding xl/worksheets/sheet1.xml breaks valid XLSX files, and how HotXLS resolves OPC relationship targets against the source part in Delphi
XLSX Pivot Field Schema Validity in Delphi with HotXLS
How HotXLS writes XLSX pivot fields that pass the ECMA-376 schema from Delphi: ST_Axis tokens, dataField flags, non-empty items, subtotal items and numFmtId
XLSX Shared Formula si Expansion in Delphi: Pitfalls
How HotXLS expands XLSX shared formula followers in Delphi: find the si master, shift relative references, and survive self-closing f elements
XLSX Sheet Protection in Delphi: 15 Allow Options
Set per-action XLSX sheet protection in Delphi with HotXLS: 15 AllowOption permission bits, the OOXML omit-equals-allow rule, and round-trip-safe parsing
Clone an XLSX Worksheet in Delphi with HotXLS
Clone a styled XLSX worksheet in Delphi with HotXLS Duplicate and CopyFrom: what deep-copies, what stays shallow, and how to rebuild charts on the copy
ZIP EOCD Validation for Untrusted XLSX Files in Delphi
How HotXLS validates the ZIP end of central directory record with four cross checks so a forged EOCD hidden in a ZIP comment cannot fool your Delphi parser
Concurrent ZIP Inflate in Delphi: HotXLS Read Gate
How HotXLS inflates many XLSX worksheets concurrently from one shared ZIP package stream in Delphi using a read gate that locks only the seek and read pair
HotXLS, zlib-ng CRC32, and Stack Overflow in Delphi Threads
HotXLS worksheet CRC32 checksums can overflow a 1 MB worker thread stack when zlib-ng selects its Chorba path; feeding data in 64 KB chunks avoids the crash