// 1. Create a new workbook and get the active worksheet IWorkbook workbook = Factory.GetWorkbook(); IWorksheet worksheet = workbook.Worksheets["Sheet1"]; worksheet.Name = "Sales Report";

var generator = new ReportGenerator(); generator.CreateSalesReport(); Console.WriteLine("Excel report generated successfully."); What Makes This Powerful? | Challenge | SpreadsheetGear Solution | |-----------|--------------------------| | Server deployment | No COM, no Excel install. Runs in any .NET app (ASP.NET, Windows Service, Azure Function). | | Performance | In-memory, thread-safe, and up to 100x faster than Interop. | | Formulas & functions | Supports 400+ built-in Excel functions, including array formulas. | | Rendering | Can convert worksheets to PDF, PNG, or HTML without Excel. | | Compatibility | Reads/writes .xls, .xlsx, .xlsm, .csv — preserves charts, pivot tables, and macros. | Real-World Use Case Extension Suppose you need to email this report as a PDF. With SpreadsheetGear, you can add two lines:

// 3. Apply formatting to headers (bold, background color) IRange headerRange = worksheet.Cells["A1:D1"]; headerRange.Font.Bold = true; headerRange.Interior.Color = System.Drawing.Color.LightGray; headerRange.Borders.LineStyle = SpreadsheetGear.Advanced.Cells.LineStyle.Continuous;

For .NET developers, programmatically creating, reading, or modifying Excel files often feels like a high-wire act. You can use Microsoft’s Office Interop—but that requires Excel to be installed, is notoriously slow, unstable in server environments, and expensive to license. Enter SpreadsheetGear : a high-performance, server-friendly .NET library that reads, writes, and renders Excel workbooks without Microsoft Excel.

public void CreateSalesReport()