XLS to XLSX using C#
The C# library for converting one Excel document to another Excel document format.
XLS to XLSX features
The C# library for converting XLS file to XLSX file.
C# library install
ConvertAPI provides an ASP.NET C# library that allows you to perform a XLS to XLSX conversion with just a few lines of code. Convert XLS to XLSX documents using C# programming language with no effort at all!
Install-Package ConvertApi
Authenticate ConvertAPI C# library
You can obtain your secret key by signing up for a free account. Once you sign up, you'll receive 250 free conversions instantly! Grab your authentication secret from the account dashboard, and authenticate the ConvertAPI C# library like this:
ConvertApi convertApi = new ConvertApi("secret_or_token");
XLS to XLSX using C# in no time!
Once you have your authentication in place, simply copy-paste this xls to xlsx conversion code snippet into your C# project:
Try the conversion online - no coding required!
You can try out advanced conversion parameters and test the conversion result online using our interactive demo tool. This tool will produce the same conversion output as if you were using the library from your solution, and it will auto-generate the code snippet for you!
Try for FREE!Conversion parameters
Sets the password to open protected documents.