XLSX to CSV conversion tutorial shows how to convert XLSX Excel files to CSV in C# or Visual Basic .NET using Bytescout Spreadsheed SDK. Use CSharp or VB.NET source code below to convert XLSX to CSV files.

C#

Spreadsheet document = new Spreadsheet())

document.LoadFromFile("SimpleReport.xlsx");
string csvFile = Path.GetTempPath() + "SimpleReport.csv";

// Save the document as CSV file
document.Workbook.Worksheets[0].SaveAsCSV(csvFile);
document.Close();

VB.NET

   ' Load XLS document
 	Dim document As New Spreadsheet()
   document.LoadFromFile("SimpleReport.xlsx")
   Dim csvFile As String = Path.GetTempPath() & "SimpleReport.csv"

   ' Save the document as CSV file
   document.Workbook.Worksheets(0).SaveAsCSV(csvFile)
   document.Close()