How to Load Existing Spreadsheets in C# ByRegan Pun April 19, 2025 Updated June 22, 2025 Share: Unlock the power of seamless Excel integration in your C# applications by watching our step-by-step tutorial on using the IronXL library—subscribe now for more expert insights from Myer Software! more... In this comprehensive tutorial, we explore how to load existing Excel spreadsheets and CSV files into a C# application using the IronXL library. To begin, ensure the IronXL NuGet package is installed in your project. This can be done easily via the NuGet package manager.Start by importing the IronXL namespace into your program's C# file and setting your IronXL license key. IronXL supports a variety of Excel formats, including XLSX, XLS, XLSM, and XLTX.By following these outlined steps, you can effectively manage existing spreadsheets and CSV files in your C# projects, leveraging the capabilities of IronXL.We hope this tutorial is beneficial. Subscribe for more informative tutorials from Myer Software, and sign up for IronXL's trial to experience its capabilities firsthand.Further Reading: How to Load Existing Spreadsheets show less