How to Write CSV in C# .NET using IronXL

Which Installation Method Should I Use?

If you haven't installed IronXL yet, follow these steps:

• Open Visual Studio and select the Project menu.
• Click Manage NuGet Packages.
• Search for IronXL.Excel.
• Click Install.

What If I Prefer the Command Line?

Use the following command in the Developer Command Prompt:

Install-Package IronXL.Excel

Where Can I Find More Resources?

For additional tutorials and guidance, visit: https://ironsoftware.com/csharp/excel/docs/. For CSV reading operations, see our guide on how to read CSV files in C#.

Download the sample project here.

How to Tutorial

What Data Should My Workbook Contain?

CSV (Comma-Separated Values) files are widely used for data exchange between applications due to their simple format and universal compatibility. Whether exporting data for analysis, creating reports, or integrating with other systems, IronXL makes the process seamless.

First, create an Excel workbook containing sample data. If you need help creating Excel files programmatically, visit our tutorial on creating Excel files in .NET:

Figure 1 - Normal Excel data to be exported to CSV

Which Namespace Do I Need to Import?

Add the IronXL namespace to write CSV files in C#:

using IronXL;

using IronXL;

Imports IronXL

What Code Do I Need to Convert Excel to CSV?

The following C# code demonstrates using the WorkBook object's Load method to load an Excel file, then using the SaveAs method to save it as CSV. This approach handles data types, special characters, and formatting automatically:

:path=/static-assets/excel/content-code-examples/how-to/csharp-write-to-csv-file-save.cs

using IronXL;

// Load the existing Excel workbook
WorkBook wb = WorkBook.Load("Normal_Excel_File.xlsx"); // Import .xls, .csv, or .tsv file

// Save the workbook as a CSV file with the worksheet name appended
wb.SaveAs("Excel_To_CSV.csv"); // Exported as: Excel_To_CSV.Sheet1.csv

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How Can I Save a Specific Worksheet to CSV?

When working with multi-sheet workbooks, you can export specific worksheets. IronXL provides flexible options for this scenario. Learn more about managing worksheets in our documentation:

using IronXL;

// Load workbook and access specific worksheet
WorkBook workBook = WorkBook.Load("MultiSheet_Excel.xlsx");
WorkSheet sheet = workBook.GetWorkSheet("Sales_Data");

// Save only the specific worksheet as CSV
sheet.SaveAsCsv("Sales_Data_Export.csv");

// Alternatively, save with custom delimiter
sheet.SaveAsCsv("Sales_Data_Tab.tsv", delimiter: "\t");

using IronXL;

// Load workbook and access specific worksheet
WorkBook workBook = WorkBook.Load("MultiSheet_Excel.xlsx");
WorkSheet sheet = workBook.GetWorkSheet("Sales_Data");

// Save only the specific worksheet as CSV
sheet.SaveAsCsv("Sales_Data_Export.csv");

// Alternatively, save with custom delimiter
sheet.SaveAsCsv("Sales_Data_Tab.tsv", delimiter: "\t");

IRON VB CONVERTER ERROR developers@ironsoftware.com

What Does the CSV Output Look Like?

The output CSV file appears as follows when opened in a text editor. Notice how IronXL properly formats the data with commas as delimiters and handles text fields containing special characters:

Figure 2 - Output CSV file

How Do I Handle Multiple Worksheets?

When your Excel file contains multiple worksheets, IronXL offers several approaches for CSV export. Explore more about converting spreadsheet file types in our comprehensive guide:

using IronXL;
using System;

// Load workbook with multiple sheets
WorkBook workBook = WorkBook.Load("MultipleSheets.xlsx");

// Method 1: Export all sheets to separate CSV files
foreach (WorkSheet sheet in workBook.WorkSheets)
{
    string fileName = $"{sheet.Name}_Export.csv";
    sheet.SaveAsCsv(fileName);
    Console.WriteLine($"Exported {sheet.Name} to {fileName}");
}

// Method 2: Combine all sheets into one CSV
var combinedData = workBook.GetWorkSheet(0);
for (int i = 1; i < workBook.WorkSheets.Count; i++)
{
    var currentSheet = workBook.GetWorkSheet(i);
    // Add logic to append data from currentSheet to combinedData
}
combinedData.SaveAsCsv("Combined_Output.csv");

using IronXL;
using System;

// Load workbook with multiple sheets
WorkBook workBook = WorkBook.Load("MultipleSheets.xlsx");

// Method 1: Export all sheets to separate CSV files
foreach (WorkSheet sheet in workBook.WorkSheets)
{
    string fileName = $"{sheet.Name}_Export.csv";
    sheet.SaveAsCsv(fileName);
    Console.WriteLine($"Exported {sheet.Name} to {fileName}");
}

// Method 2: Combine all sheets into one CSV
var combinedData = workBook.GetWorkSheet(0);
for (int i = 1; i < workBook.WorkSheets.Count; i++)
{
    var currentSheet = workBook.GetWorkSheet(i);
    // Add logic to append data from currentSheet to combinedData
}
combinedData.SaveAsCsv("Combined_Output.csv");

IRON VB CONVERTER ERROR developers@ironsoftware.com

What About Performance Considerations?

For large Excel files, IronXL provides efficient streaming capabilities that minimize memory usage. When working with substantial datasets, use IronXL's optimized methods. See our guide on exporting data to various formats for advanced scenarios.

Can I Work with DataTables?

IronXL seamlessly integrates with .NET's DataTable structure, making it easy to export data from databases or in-memory collections. See our tutorial on converting DataTable to CSV:

using IronXL;
using System.Data;

// Create a DataTable with sample data
DataTable dataTable = new DataTable();
dataTable.Columns.Add("ID", typeof(int));
dataTable.Columns.Add("Name", typeof(string));
dataTable.Columns.Add("Price", typeof(decimal));

// Add sample rows
dataTable.Rows.Add(1, "Product A", 29.99m);
dataTable.Rows.Add(2, "Product B", 49.99m);

// Convert DataTable to WorkSheet
WorkBook workBook = WorkBook.Create();
WorkSheet sheet = workBook.CreateWorkSheet("Products");
sheet.InsertDataTable(dataTable, "A1");

// Save as CSV
workBook.SaveAsCsv("Products.csv");

using IronXL;
using System.Data;

// Create a DataTable with sample data
DataTable dataTable = new DataTable();
dataTable.Columns.Add("ID", typeof(int));
dataTable.Columns.Add("Name", typeof(string));
dataTable.Columns.Add("Price", typeof(decimal));

// Add sample rows
dataTable.Rows.Add(1, "Product A", 29.99m);
dataTable.Rows.Add(2, "Product B", 49.99m);

// Convert DataTable to WorkSheet
WorkBook workBook = WorkBook.Create();
WorkSheet sheet = workBook.CreateWorkSheet("Products");
sheet.InsertDataTable(dataTable, "A1");

// Save as CSV
workBook.SaveAsCsv("Products.csv");

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How Do I Set Up Licensing?

Before deploying your CSV export solution, configure your IronXL license properly. Visit our guide on using license keys to learn about applying licenses in different environments.

Library Quick Access

IronXL API Reference Documentation

Learn more and share how to merge, unmerge, and work with cells in Excel spreadsheets using the IronXL API Reference Documentation. For detailed method signatures and additional CSV export options, consult our [API Reference](https://ironsoftware.com/csharp/excel/object-reference/api/).

IronXL API Reference Documentation