Tag: #javascript
5 articles
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Stop Bad Data at the Cell — Data Validation in a JavaScript Spreadsheet
Dropdown lists, numeric and date bounds, custom formula checks — reject invalid input the moment it's typed, with zero form-validation code. A full order-entry example using ReoGrid Web's Excel-style data validation, including input prompts, error alerts, and xlsx round-trip.
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Convert XLSX to JSON in the browser — no server, no upload
Turn an .xlsx file into JSON entirely client-side: lossless ReoGrid JSON for round-tripping, or plain data rows for your app. Practical code, files never leave the browser.
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Traffic-Light Dashboards in a JavaScript Spreadsheet — Conditional Formatting by Example
Color-code a spreadsheet by its values — red stock warnings, green over-target sales, status-tinted rows — without writing a single styling loop. A full worked example using ReoGrid Web's three conditional-formatting rule types, with live re-evaluation as data changes.
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One million rows in a browser spreadsheet — without loading one million rows
Three weeks ago we wrote that a million rows was out of scope for ReoGrid Web. We changed our mind. Here's the delay-load data source: a scrollbar that represents 1,000,000 rows while the grid holds only the few hundred you can actually see.
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Reading and writing Excel files in JavaScript — import, export, and JSON
How to load .xlsx files into the browser, export a grid back to Excel, and convert between xlsx and JSON — all client-side, with styles and formats preserved. Practical code with ReoGrid Web.