Websheet: Open-Source Front-End Library for Rendering Excel Files in Browser

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Websheet is a front-end spreadsheet display control built on HTML5 Canvas and JavaScript that enables Excel (XLSX) file rendering directly in the browser. The library supports a wide range of features including file import and export, cell formatting, merged cells, formula parsing, and row or column management. Developers can interact with it programmatically through scripting support for sheet operations, view freezing, table management, and print functionality. It also exposes a set of events such as cell value changes and sheet switches, and allows customization of functions, display controls, and right-click menus. The project is available for non-commercial use, with commercial licensing requiring prior permission from the developer.

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