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
Software Development Blog
Software Development Blog
How HotXLS reads Agile-encrypted XLSX in Delphi: OpenEncrypted parses EncryptionInfo, runs SHA-512 spin-count key derivation, then decrypts AES-CBC segments
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
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.
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.
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.
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.
Add dropdown validation, AutoFilter criteria, and Excel tables from Delphi with HotXLS, including server-side filter preview and the 0-based column ID trap.
Export TDataset results to Excel from Delphi with HotXLS: TDataToXLS grouping and paging, the VCL dependency trap, XLSX conversion, and a service-safe loop.
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
Create workbook-scoped and sheet-scoped defined names with HotXLS in Delphi, write cross-sheet formulas that survive edits, and avoid _xlnm name conflicts.
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.
Evaluate Excel formulas in Delphi with HotXLS: the Calculate engine, OnUserFunction custom functions, array formulas, and why CSV export needs computed values.
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.
Size embedded XLSX images by physical dimensions in Delphi with HotXLS: EMU units explained, centimetre and point geometry, aspect-locked scaling, cm margins.
HotXLS Workbook.Recalculate builds a formula dependency graph in Delphi to re-evaluate only dirty cells: volatile functions, topological order, cycle handling
Practical HotXLS performance tuning for large Excel files in Delphi: StreamingWrite saves, style pool reuse, row callbacks, and faster read-only loads
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
How HotXLS handles merged cells in Delphi report templates: anchor-cell semantics, InsertRows shifting rules, merge audits, and HTML and RTF export behaviour.
HotXLS opens and saves OpenDocument Spreadsheet files from Delphi: SaveAsODS export options, the lightweight ODS import path, and what survives a round trip.
Two encryption bugs 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
Build XLS and XLSX workbooks from Delphi services without installing Excel: native BIFF and OOXML writers, stream output to HTTP responses, COM-free.
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
Protect worksheets, keep input ranges editable, and control print layout in Delphi with HotXLS: Locked flags, page setup, scaling, and header codes
Read worksheet names from XLS, XLSX, and ODS files in Delphi without loading cell data: HotXLS GetSheetNames, encrypted-file detection, intake triage.
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
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.
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.
Keep large XLSX exports inside memory limits with HotXLS StreamingWrite, row-level write callbacks, style pool reuse, and per-thread batch workbook jobs
Fill Excel report templates from Delphi with HotXLS: locate placeholders with FindText, clone detail rows, insert rows safely, and recalculate before saving
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.
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.
Audit unknown Excel files from Delphi with HotXLS: count charts, formulas, macros, and protection, then convert XLS, XLSX, and ODS with known fidelity limits.
Set and read Excel document properties from Delphi with HotXLS: title, author, company, and keywords across BIFF SummaryInformation and OOXML docProps parts.
Write AES-encrypted XLSX files from Delphi with HotXLS SaveAsEncrypted: ECMA-376 Standard Encryption, password handling, and the write-only decryption limit.
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 a styled XLSX worksheet in Delphi with HotXLS Duplicate and CopyFrom, including what deep-copies, what stays shallow, and how to rebuild charts on the copy.