The C# XLSX Library

Read & Write XLSX files in C# & VB .NET
Convert XLS to XLSX + Datatable to XLSX file
Create XLSX file in C# with no need for MS Office or Excel Interop

XLSX Code Samples

Convert XLSX Spreadsheet File Types

using IronXL;
using System.IO;

// Import any XLSX, XLS, XLSM, XLTX, CSV and TSV
WorkBook workBook = WorkBook.Load("sample.xlsx");

// Export the excel file as XLS, XLSX, XLSM, CSV, TSV, JSON, XML
workBook.SaveAs("sample.xls");
workBook.SaveAs("sample.xlsx");
workBook.SaveAs("sample.tsv");
workBook.SaveAsCsv("sample.csv");
workBook.SaveAsJson("sample.json");
workBook.SaveAsXml("sample.xml");

// Export the excel file as Html, Html string
workBook.ExportToHtml("sample.html");
string htmlString = workBook.ExportToHtmlString();

// Export the excel file as Binary, Byte array, Data set, Stream
byte[] binary = workBook.ToBinary();
byte[] byteArray = workBook.ToByteArray();
System.Data.DataSet dataSet = workBook.ToDataSet(); // Allow easy integration with DataGrids, SQL and EF
Stream stream = workBook.ToStream();

Imports IronXL
Imports System.IO

' Import any XLSX, XLS, XLSM, XLTX, CSV and TSV
Dim workBook As WorkBook = WorkBook.Load("sample.xlsx")

' Export the excel file as XLS, XLSX, XLSM, CSV, TSV, JSON, XML
workBook.SaveAs("sample.xls")
workBook.SaveAs("sample.xlsx")
workBook.SaveAs("sample.tsv")
workBook.SaveAsCsv("sample.csv")
workBook.SaveAsJson("sample.json")
workBook.SaveAsXml("sample.xml")

' Export the excel file as Html, Html string
workBook.ExportToHtml("sample.html")
Dim htmlString As String = workBook.ExportToHtmlString()

' Export the excel file as Binary, Byte array, Data set, Stream
Dim binary As Byte() = workBook.ToBinary()
Dim byteArray As Byte() = workBook.ToByteArray()
Dim dataSet As System.Data.DataSet = workBook.ToDataSet() ' Allow easy integration with DataGrids, SQL and EF
Dim stream As Stream = workBook.ToStream()

PM > Install-Package IronXL.Excel

Install-Package IronXL.Excel

IronXL offers a simple and flexible way for developers to work with Excel files, allowing easy import and export across various formats. It supports file types like XLS, XLSX, CSV, JSON, XML, and HTML, making it ideal for different application needs. Developers can convert Excel data into formats suitable for web integration, APIs, or further data processing with just a few lines of code.

For example, exporting Excel files as HTML or JSON makes it easy to embed data into web applications, while converting them to binary, byte arrays, or streams helps integrate with databases or other systems. Converting Excel content into a DataSet simplifies connecting to SQL databases or populating UI components like data grids. This reduces manual coding, enhances productivity, and makes IronXL a valuable tool for modern, data-driven applications.

5 Steps to Export Excel Files in Multiple Formats

This code demonstrates the versatility of IronXL in handling and exporting Excel data across multiple formats. The process begins by loading an existing Excel file, Sample.xlsx, into a WorkBook object. This object acts as the central hub for manipulating and exporting data. Using the SaveAs method, the workbook is saved as a .xlsx file, ensuring compatibility with modern Excel applications.

Next, the SaveAsJson method converts the workbook into JSON format, making it suitable for API responses or lightweight data exchanges. The ToDataSet method enables seamless integration with databases or UI components by converting the workbook into a DataSet object, which is a .NET-native structure for handling tabular data.

Finally, the ExportToHtml method generates an HTML file, enabling developers to display the Excel data directly on web pages. These capabilities streamline data processing tasks, making IronXL an exceptional tool for developers working with Excel files.

Learn to Convert Excel File Types Effortlessly

Read Excel Files without Interop

using IronXL;
using System;
using System.Linq;

// Supported for XLSX, XLS, XLSM, XLTX, CSV and TSV
WorkBook workBook = WorkBook.Load("sample.xlsx");

// Select worksheet at index 0
WorkSheet workSheet = workBook.WorkSheets[0];

// Get any existing worksheet
WorkSheet firstSheet = workBook.DefaultWorkSheet;

// Select a cell and return the converted value
int cellValue = workSheet["A2"].IntValue;

// Read from ranges of cells elegantly.
foreach (var cell in workSheet["A2:A10"])
{
    Console.WriteLine("Cell {0} has value '{1}'", cell.AddressString, cell.Text);
}

// Calculate aggregate values such as Min, Max and Sum
decimal sum = workSheet["A2:A10"].Sum();

// Linq compatible
decimal max = workSheet["A2:A10"].Max(c => c.DecimalValue);

Imports IronXL
Imports System
Imports System.Linq

' Supported for XLSX, XLS, XLSM, XLTX, CSV and TSV
Dim workBook As WorkBook = WorkBook.Load("sample.xlsx")

' Select worksheet at index 0
Dim workSheet As WorkSheet = workBook.WorkSheets(0)

' Get any existing worksheet
Dim firstSheet As WorkSheet = workBook.DefaultWorkSheet

' Select a cell and return the converted value
Dim cellValue As Integer = workSheet("A2").IntValue

' Read from ranges of cells elegantly.
For Each cell In workSheet("A2:A10")
    Console.WriteLine("Cell {0} has value '{1}'", cell.AddressString, cell.Text)
Next

' Calculate aggregate values such as Min, Max and Sum
Dim sum As Decimal = workSheet("A2:A10").Sum()

' Linq compatible
Dim max As Decimal = workSheet("A2:A10").Max(Function(c) c.DecimalValue)

PM > Install-Package IronXL.Excel

Install-Package IronXL.Excel

The Load feature in IronXL allows you to easily load and manipulate existing Excel files in various formats (XLSX, XLS, CSV, etc.). By loading a WorkBook, you gain access to its WorkSheets and data, enabling you to extract values, loop through cell ranges, and perform calculations like sums or maximum values. You can access specific cells, convert their values to the appropriate data type (e.g., integers, decimals), and even use LINQ for advanced data operations. This feature simplifies working with Excel data in .NET, making it ideal for tasks like data analysis, report generation, and automation.

5 Steps to Load and Calculate Sum from an Excel File

WorkBook workBook = WorkBook.Load("sample.xlsx");
WorkSheet workSheet = workBook.WorkSheets[0];
var range = workSheet["A2:A10"];
decimal sum = range.Sum();
Console.WriteLine("The sum of the range A2:A10 is: " + sum);

The WorkBook object is the key starting point for interacting with Excel files in IronXL. By using the WorkBook.Load("sample.xlsx") method, you open an existing Excel file, gaining access to its content and structure for further manipulation. This allows developers to work with pre-existing data, automate tasks, and update spreadsheets without having to create a new one from scratch.

Next, the WorkSheets[0] property is used to access the first worksheet in the workbook. In Excel, a workbook can contain multiple sheets, each representing a set of data organized into rows and columns. By selecting the first sheet, you're targeting the main area where your data is stored or where you'll perform operations like reading values or calculating results.

The range variable defines a specific group of cells, in this case, the range from A2 to A10. This is where IronXL allows you to interact with multiple cells at once, either by reading values, applying formatting, or performing calculations across ranges. In this example, it captures a column range, making it easy to work with sequential data.

The .Sum() method is used to calculate the sum of the numeric values in the selected range. This highlights how IronXL allows developers to perform quick, built-in calculations on ranges of data, eliminating the need for manual iteration and summing.

Finally, the Console.WriteLine() statement outputs the calculated sum to the console. This is a simple but powerful way to display the result of your operations, such as the sum of values in a range, directly within your application.

With this approach, developers can easily automate data aggregation tasks or integrate them into larger workflows.

Learn to Load and Manipulate Excel Files with IronXL

Work with Excel WorkSheets

using IronXL;

// Create new Excel spreadsheet
WorkBook workBook = WorkBook.Create(ExcelFileFormat.XLSX);

// Create worksheets (workSheet1, workSheet2, workSheet3)
WorkSheet workSheet1 = workBook.CreateWorkSheet("workSheet1");
WorkSheet workSheet2 = workBook.CreateWorkSheet("workSheet2");
WorkSheet workSheet3 = workBook.CreateWorkSheet("workSheet3");

// Set worksheet position (workSheet2, workSheet1, workSheet3)
workBook.SetSheetPosition("workSheet2", 0);

// Set active for workSheet3
workBook.SetActiveTab(2);

// Remove workSheet1
workBook.RemoveWorkSheet(1);

workBook.SaveAs("manageWorkSheet.xlsx");

Imports IronXL

' Create new Excel spreadsheet
Dim workBook As WorkBook = WorkBook.Create(ExcelFileFormat.XLSX)

' Create worksheets (workSheet1, workSheet2, workSheet3)
Dim workSheet1 As WorkSheet = workBook.CreateWorkSheet("workSheet1")
Dim workSheet2 As WorkSheet = workBook.CreateWorkSheet("workSheet2")
Dim workSheet3 As WorkSheet = workBook.CreateWorkSheet("workSheet3")

' Set worksheet position (workSheet2, workSheet1, workSheet3)
workBook.SetSheetPosition("workSheet2", 0)

' Set active for workSheet3
workBook.SetActiveTab(2)

' Remove workSheet1
workBook.RemoveWorkSheet(1)

workBook.SaveAs("manageWorkSheet.xlsx")

PM > Install-Package IronXL.Excel

Install-Package IronXL.Excel

IronXL library makes managing worksheets using C# code as easy as possible. The actions of creating & deleting worksheets, changing worksheet positions, and setting the active worksheet in an Excel file can be achieved without using Office Interop.

Create Worksheet

The CreateWorkSheet method allows creating a worksheet. It requires the worksheet name as the only parameter.

This code snippet creates a new workbook and a new worksheet named "NewSheet" within that workbook.

Set Worksheet Position

The SetSheetPosition method can be used to change or move a worksheet's position. Two parameters are required: the worksheet name as a string and its index position as an integer.

This modifies the position of the worksheet named "SheetName" to the second position in the workbook (remember, indexing is zero-based).

Set Active Worksheet

Setting the active worksheet means setting which worksheet will be opened by default when the workbook is accessed. To achieve this, use the SetActiveTab method with the index position of the worksheet.

This sets the first worksheet as the active tab that opens by default.

Remove Worksheet

Removing a worksheet can also be done with IronXL. Use the RemoveWorkSheet method along with the index position of the worksheet. If the worksheet's position is unknown, the name of the worksheet can also be used to delete it.

The first example removes the first worksheet in the workbook by index.
The second example removes the worksheet named "SheetName".

Please note that all the index positions mentioned above utilize zero-based indexing, meaning the first element has an index of 0.

How to Manage an Excel Worksheet in C#

Install the C# library to manage worksheets in Excel
Utilize the CreateWorkSheet method to create a worksheet
Change the worksheet position in C# with SetSheetPosition
Use SetActiveTab to set which worksheet is opened by default
Remove or delete a worksheet using the RemoveWorkSheet C# function

Create a new Excel File

using IronXL;

// Create new Excel WorkBook document
WorkBook workBook = WorkBook.Create();

// Convert XLSX to XLS
WorkBook xlsWorkBook = WorkBook.Create(ExcelFileFormat.XLS);

// Create a blank WorkSheet
WorkSheet workSheet = workBook.CreateWorkSheet("new_sheet");

// Add data and styles to the new worksheet
workSheet["A1"].Value = "Hello World";
workSheet["A1"].Style.WrapText = true;
workSheet["A2"].BoolValue = true;
workSheet["A2"].Style.BottomBorder.Type = IronXL.Styles.BorderType.Double;

// Save the excel file as XLS, XLSX, CSV, TSV, JSON, XML, HTML and streams
workBook.SaveAs("sample.xlsx");

Imports IronXL

' Create new Excel WorkBook document
Dim workBook As WorkBook = WorkBook.Create()

' Convert XLSX to XLS
Dim xlsWorkBook As WorkBook = WorkBook.Create(ExcelFileFormat.XLS)

' Create a blank WorkSheet
Dim workSheet As WorkSheet = workBook.CreateWorkSheet("new_sheet")

' Add data and styles to the new worksheet
workSheet("A1").Value = "Hello World"
workSheet("A1").Style.WrapText = True
workSheet("A2").BoolValue = True
workSheet("A2").Style.BottomBorder.Type = IronXL.Styles.BorderType.Double

' Save the excel file as XLS, XLSX, CSV, TSV, JSON, XML, HTML and streams
workBook.SaveAs("sample.xlsx")

PM > Install-Package IronXL.Excel

Install-Package IronXL.Excel

The Create Excel feature provides developers with a powerful way to generate and manage Excel files directly within .NET applications.

It streamlines tasks like creating new workbooks, adding worksheets, and inputting data while offering advanced styling options such as text wrapping, borders, and formatting. This feature is perfect for automating reports, exporting data, or creating dynamic spreadsheets. IronXL supports multiple file formats, including XLS, XLSX, CSV, and more, ensuring compatibility with various systems. With its user-friendly API, developers can focus on core functionality while saving time and reducing complexity in Excel file management.

5 Steps to Create and Style Excel Files with IronXL

WorkBook workBook = WorkBook.Create();
WorkSheet workSheet = workBook.CreateWorkSheet("new_sheet");
workSheet["A1"].Value = "Hello World";
workSheet["A1"].Style.WrapText = true;
workBook.SaveAs("sample.xlsx");

The WorkBook object serves as the foundation of any Excel file. By initializing a new workbook, developers gain access to a blank Excel document, ready to be populated with data and formatted as needed.

Every Excel workbook requires at least one worksheet. The next step demonstrates how to create a new sheet within the workbook and assign it a custom name. Worksheets act as the primary structure for organizing data in rows and columns.

The snippet demonstrates how to add content by assigning the value "Hello World" to a specific cell, A1. This shows how easy it is to populate data into an Excel sheet programmatically, enabling developers to automate tasks like report generation and data export.

Additionally, the snippet applies styling to the cell by enabling the WrapText property. This ensures that lengthy content in the cell is displayed neatly across multiple lines, improving readability and preventing text from being cut off. Such styling options empower developers to create visually appealing and professional spreadsheets.

Explore the Step-by-Step Guide to Create Excel Files in C#

Excel to SQL via System.Data.DataSet

using IronXL;
using System;
using System.Data;

// Supported for XLSX, XLS, XLSM, XLTX, CSV and TSV
WorkBook workBook = WorkBook.Load("sample.xlsx");

// Convert the whole Excel WorkBook to a DataSet
DataSet dataSet = workBook.ToDataSet();

foreach (DataTable table in dataSet.Tables)
{
    Console.WriteLine(table.TableName);

    // Enumerate by rows or columns first at your preference
    foreach (DataRow row in table.Rows)
    {
        for (int i = 0 ; i < table.Columns.Count ; i++)
        {
            Console.Write(row[i]);
        }
    }
}

Imports IronXL
Imports System
Imports System.Data

' Supported for XLSX, XLS, XLSM, XLTX, CSV and TSV
Dim workBook As WorkBook = WorkBook.Load("sample.xlsx")

' Convert the whole Excel WorkBook to a DataSet
Dim dataSet As DataSet = workBook.ToDataSet()

For Each table As DataTable In dataSet.Tables
    Console.WriteLine(table.TableName)

    ' Enumerate by rows or columns first at your preference
    For Each row As DataRow In table.Rows
        For i As Integer = 0 To table.Columns.Count - 1
            Console.Write(row(i))
        Next
    Next
Next

PM > Install-Package IronXL.Excel

Install-Package IronXL.Excel

Convert any XLSX, XLS, XLSM, XLTX, CSV, and TSV file to a System.Data.DataTable for full interoperability with System.Data.SQL or to populate a DataGrid. This DataTable object can contain a collection of tables, relationships, and constraints.

Learn how to export DataTables in C# with our guide.

Excel to SQL and DataGrid via DataTable

using IronXL;
using System;
using System.Data;

// Supported for XLSX, XLS, XLSM, XLTX, CSV and TSV
WorkBook workBook = WorkBook.Load("sample.xlsx");

// Select default sheet
WorkSheet workSheet = workBook.DefaultWorkSheet;

// Convert the worksheet to DataTable
DataTable dataTable = workSheet.ToDataTable(true);

// Enumerate by rows or columns first at your preference
foreach (DataRow row in dataTable.Rows)
{
    for (int i = 0 ; i < dataTable.Columns.Count ; i++)
    {
        Console.Write(row[i]);
    }
}

Imports IronXL
Imports System
Imports System.Data

' Supported for XLSX, XLS, XLSM, XLTX, CSV and TSV
Dim workBook As WorkBook = WorkBook.Load("sample.xlsx")

' Select default sheet
Dim workSheet As WorkSheet = workBook.DefaultWorkSheet

' Convert the worksheet to DataTable
Dim dataTable As DataTable = workSheet.ToDataTable(True)

' Enumerate by rows or columns first at your preference
For Each row As DataRow In dataTable.Rows
    For i As Integer = 0 To dataTable.Columns.Count - 1
        Console.Write(row(i))
    Next
Next

PM > Install-Package IronXL.Excel

Install-Package IronXL.Excel

Convert XLSX, XLS, XLSM, XLTX, CSV and TSV files to a System.Data.DataTable for full interoperability with System.Data.SQL or to populate a DataGrid.

Input true to ToDataTable method to set the first row as column names of the table. The DataTable can populate a DataGrid.

How to Convert Excel to SQL `DataTable` in C#

Install an Excel library to convert Excel to SQL DataTable.

Select the default Worksheet

Create a DataTable from data using ToDataTable.

Process values iteratively.

Learn to Export DataTable to Excel in C#

Support from our Excel Team

Iron's Excel product team is available to support all of your questions. Get in touch to ask a question on how our library can help you in your project.

Raise a Support Ticket

Create XLSX files in .NET

Create and Edit Spreadsheet files in C#. Works with Dotnet Core and Azure with no need to install MS Office or Interop.

Features

Read & Write Multiple Formats

IronXL allows you to quickly read & write Excel Spreadsheets in your .NET APPs. Read & Edit XLS/XLSX/CSV/TSV - Save & Export to XLS/XLSX/CSV/TSV/JSON. IronXL outperforms free & Interop libraries parsing, editing, & saving Excel files.

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