Convert Excel file to CSV in C#, VB.NET

Syncfusion Excel (XlsIO) library is a .NET Excel library used to create, read, and edit Excel documents. Also, converts Excel documents to PDF files. Using this library, you can convert an Excel file with simple text into CSV file.

Steps to convert Excel file to CSV file programmatically:

Step 1: Create a new C# console application project.

Create a new C# console application

Step 2: Install the Syncfusion.XlsIO.WinForms NuGet package as reference to your .NET Framework applications from NuGet.org.

Install NuGet package

Step 3: Include the following namespace in the Program.cs file.

C#

using Syncfusion.XlsIO;

VB.NET

Imports Syncfusion.XlsIO

Step 4: Use the following code snippet to convert an Excel file with simple text into CSV file.

C#

//Initialize ExcelEngine.
using (ExcelEngine excelEngine = new ExcelEngine())
{
    //Initialize Application.
    IApplication application = excelEngine.Excel;
 
    //Set default version for application.
    application.DefaultVersion = ExcelVersion.Excel2013;
 
    //Create a new workbook.
    IWorkbook workbook = application.Workbooks.Create(1);
 
    //Accessing first worksheet in the workbook.
    IWorksheet worksheet = workbook.Worksheets[0];
 
    //Adding text to a cell
    worksheet.Range["A1:N30"].Text = "Hello World";
 
    //Save the workbook to csv format.
    worksheet.SaveAs("Sample.csv", ",");
}

VB.NET

'Initialize ExcelEngine.
Using excelEngine As ExcelEngine = New ExcelEngine
 
    'Initialize Application.
    Dim application As IApplication = excelEngine.Excel
 
    'Set default version for application.
    application.DefaultVersion = ExcelVersion.Excel2013
 
    'Create a new workbook.
    Dim workbook As IWorkbook = application.Workbooks.Create(1)
 
    'Accessing first worksheet in the workbook.
    Dim worksheet As IWorksheet = workbook.Worksheets(0)
 
    'Adding text to a cell
    worksheet.Range("A1:N30").Text = "Hello World"
 
    'Save the workbook to csv format.
    worksheet.SaveAs("Sample.csv", ",")
 
End Using

A complete working example to convert an Excel file to CSV can be downloaded from Convert Excel File To CSV File.zip.

SaveAs() method saves a workbook with the specified file name. SaveAs() method has three overloads to convert Excel file to CSV whose API references are as follows:

1. SaveAs(String,String)
2. SaveAs(String,String,Encoding)
3. SaveAs(Stream,String)
4. SaveAs(Stream,String,Encoding)

By executing the program, you will get the output Excel file as shown below.

Output Excel document

Take a moment to peruse the documentation, where you can find basic worksheet data manipulation options along with features like Conditional Formatting, worksheet calculations through Formulas, adding Charts in worksheet or workbook, organizing and analyzing data through Tables and Pivot Tables, appending multiple records to worksheet using Template Markers, and most importantly PDF and Image conversions etc., with code examples.

Refer here to explore the rich set of Syncfusion Excel (XlsIO) library features.

An online sample link to convert Excel file to CSV file.