Extract Text from XLSX using C#. For more information, please follow link: https://kb.groupdocs.com/parser/net/extract-text-from-xlsx-using-csharp/

Extract Text from XLSX using C#.cs

using System;
using System.IO;
using GroupDocs.Parser;
using GroupDocs.Parser.Options;

namespace ExtractTextfromXLSXusingCSharp
{
    internal class Program
    {
        static void Main(string[] args)
        {
            // Apply the license to remove the limitations of the Parser library
            License lic = new License();
            lic.SetLicense(@"GroupDocs.Parser.lic");
            
            // Instantiate the Parser class
            using (Parser parser = new Parser("input.xlsx"))
            {
                // Retrieve formatted text into the reader
                using (TextReader reader = parser.GetFormattedText(
                    new FormattedTextOptions(FormattedTextMode.Html)))
                {
                    // Output the formatted text from the document
                    // If formatted text extraction is not supported, 
                    // the reader will be null
                    Console.WriteLine(reader == null ? 
                                      "Formatted text extraction isn't supported" 
                                      : reader.ReadToEnd());
                    Console.ReadLine();
                }
            }
        }
    }
}