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USING IRONXL

Work with Excel in .NET Core

.NET Core Excel Overview

In this modern era, we need a better way to work with Excel Spreadsheets in our .NET Core applications. In the following tutorial, we will learn how to access spreadsheets in .NET Core Excel projects and modify their values using C#.

.NET Core Excel Editing

  • Download the IronXL Library
  • Assign values to a cell range
  • Edit cells using user inputs
  • Edit multiple cells using a static value
How To Work related to .NET Core Excel Overview

Step 1

1. Download IronXL Library

For an easy way to work with Excel files in .NET Core, try IronXL. Download IronXL DLL or install with NuGet for free use in development projects.

# Install IronXL using the .NET CLI
dotnet add package IronXL.Excel
# Install IronXL using the .NET CLI
dotnet add package IronXL.Excel
SHELL

How to Tutorial

2. .NET Core Excel Editing Project

Now that you've downloaded IronXL, let's get started. Load an Excel file in the project and access the WorkSheet where data needs to be edited and changes made.


3. Edit Specific Cell Value

For editing Excel files, add the reference IronXL to your project and import the library by using IronXL.

3.1. Load a Sample File

In the following case, our Excel file name is sample.xlsx and it exists in the bin> Debug> netcoreapp3.1 folder of the project. We will use this code to edit the value new value in cell A1 of sample.xlsx.

// Anchor: Load a sample file
using IronXL;

static void Main(string[] args)
{
    // Load the Excel workbook
    WorkBook wb = WorkBook.Load("sample.xlsx");

    // Get the first worksheet named "Sheet1"
    WorkSheet ws = wb.GetWorkSheet("Sheet1");

    // Access cell A1 and set its value to "new value"
    ws["A1"].Value = "new value";

    // Save the changes to the Excel workbook
    wb.SaveAs("sample.xlsx");
}
// Anchor: Load a sample file
using IronXL;

static void Main(string[] args)
{
    // Load the Excel workbook
    WorkBook wb = WorkBook.Load("sample.xlsx");

    // Get the first worksheet named "Sheet1"
    WorkSheet ws = wb.GetWorkSheet("Sheet1");

    // Access cell A1 and set its value to "new value"
    ws["A1"].Value = "new value";

    // Save the changes to the Excel workbook
    wb.SaveAs("sample.xlsx");
}
' Anchor: Load a sample file
Imports IronXL

Shared Sub Main(ByVal args() As String)
	' Load the Excel workbook
	Dim wb As WorkBook = WorkBook.Load("sample.xlsx")

	' Get the first worksheet named "Sheet1"
	Dim ws As WorkSheet = wb.GetWorkSheet("Sheet1")

	' Access cell A1 and set its value to "new value"
	ws("A1").Value = "new value"

	' Save the changes to the Excel workbook
	wb.SaveAs("sample.xlsx")
End Sub
$vbLabelText   $csharpLabel

4. Assign Value to Multiple Cells

It is very easy to edit multiple cells and assign static values at a time by using a colon :. Its left side indicates the starting cell and the right side indicates the last cell of a specific column.

sheet[From:To]

This will edit new value from cell A1 to A9 of column A.

// Anchor: Assign Value to Multiple Cells
using IronXL;

static void Main(string[] args)
{
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");

    // Set the value "new value" for cells from A1 to A9
    ws["A1:A9"].Value = "new value";

    wb.SaveAs("sample.xlsx");
}
// Anchor: Assign Value to Multiple Cells
using IronXL;

static void Main(string[] args)
{
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");

    // Set the value "new value" for cells from A1 to A9
    ws["A1:A9"].Value = "new value";

    wb.SaveAs("sample.xlsx");
}
' Anchor: Assign Value to Multiple Cells
Imports IronXL

Shared Sub Main(ByVal args() As String)
	Dim wb As WorkBook = WorkBook.Load("sample.xlsx")
	Dim ws As WorkSheet = wb.GetWorkSheet("Sheet1")

	' Set the value "new value" for cells from A1 to A9
	ws("A1:A9").Value = "new value"

	wb.SaveAs("sample.xlsx")
End Sub
$vbLabelText   $csharpLabel

5. Edit Cells with User Inputs

Here is an alternative case where we can take the values from the users and edit the Excel file.

// Anchor: Edit Cells with User Inputs
using System;
using IronXL;

static void Main(string[] args)
{
    string _from, _to, newValue;

    // Capture user inputs
    Console.Write("Enter Starting Cell: ");
    _from = Console.ReadLine();

    Console.Write("Enter Last Cell: ");
    _to = Console.ReadLine();

    Console.Write("Enter value: ");
    newValue = Console.ReadLine();

    // Load the Excel workbook and access the worksheet
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");

    // Assign the user-entered value to the specified cell range
    ws[_from + ":" + _to].Value = newValue;

    // Save changes to the workbook
    wb.SaveAs("sample.xlsx");

    Console.WriteLine("Successfully Changed...!");
    Console.ReadKey();
}
// Anchor: Edit Cells with User Inputs
using System;
using IronXL;

static void Main(string[] args)
{
    string _from, _to, newValue;

    // Capture user inputs
    Console.Write("Enter Starting Cell: ");
    _from = Console.ReadLine();

    Console.Write("Enter Last Cell: ");
    _to = Console.ReadLine();

    Console.Write("Enter value: ");
    newValue = Console.ReadLine();

    // Load the Excel workbook and access the worksheet
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");

    // Assign the user-entered value to the specified cell range
    ws[_from + ":" + _to].Value = newValue;

    // Save changes to the workbook
    wb.SaveAs("sample.xlsx");

    Console.WriteLine("Successfully Changed...!");
    Console.ReadKey();
}
' Anchor: Edit Cells with User Inputs
Imports System
Imports IronXL

Shared Sub Main(ByVal args() As String)
	Dim _from, _to, newValue As String

	' Capture user inputs
	Console.Write("Enter Starting Cell: ")
	_from = Console.ReadLine()

	Console.Write("Enter Last Cell: ")
	_to = Console.ReadLine()

	Console.Write("Enter value: ")
	newValue = Console.ReadLine()

	' Load the Excel workbook and access the worksheet
	Dim wb As WorkBook = WorkBook.Load("sample.xlsx")
	Dim ws As WorkSheet = wb.GetWorkSheet("Sheet1")

	' Assign the user-entered value to the specified cell range
	ws(_from & ":" & _to).Value = newValue

	' Save changes to the workbook
	wb.SaveAs("sample.xlsx")

	Console.WriteLine("Successfully Changed...!")
	Console.ReadKey()
End Sub
$vbLabelText   $csharpLabel

The above code will display a console for user inputs and then update the specified Excel cells with the entered value.

Work with Excel in .NET Core, Figure 1: Console Application UI with user input Console Application UI with user input

Values changed from B4 to B9 in ExcelSheet, as can be seen:

Work with Excel in .NET Core, Figure 2: The new value is filled from B4 to B9 The new value is filled from B4 to B9


6. Edit Multiple Cells with Static Value

It is very easy to edit multiple cells and assign dynamic values. Let's see the following example:

// Anchor: Edit Multiple Cells with Static Value
using IronXL;

static void Main(string[] args)
{
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");

    // Ensure 'from' and 'to' are defined for the intended cell range
    int from = 1;
    int to = 9;

    // Iterate over a range of cells and update them with dynamic values
    for (int i = from; i <= to; i++)
    {
        ws["A" + i].Value = "Value" + i;
    }

    // Save the changes to the Excel file
    wb.SaveAs("sample.xlsx");
}
// Anchor: Edit Multiple Cells with Static Value
using IronXL;

static void Main(string[] args)
{
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");

    // Ensure 'from' and 'to' are defined for the intended cell range
    int from = 1;
    int to = 9;

    // Iterate over a range of cells and update them with dynamic values
    for (int i = from; i <= to; i++)
    {
        ws["A" + i].Value = "Value" + i;
    }

    // Save the changes to the Excel file
    wb.SaveAs("sample.xlsx");
}
' Anchor: Edit Multiple Cells with Static Value
Imports IronXL

Shared Sub Main(ByVal args() As String)
	Dim wb As WorkBook = WorkBook.Load("sample.xlsx")
	Dim ws As WorkSheet = wb.GetWorkSheet("Sheet1")

	' Ensure 'from' and 'to' are defined for the intended cell range
	Dim from As Integer = 1
	Dim [to] As Integer = 9

	' Iterate over a range of cells and update them with dynamic values
	For i As Integer = From To [to]
		ws("A" & i).Value = "Value" & i
	Next i

	' Save the changes to the Excel file
	wb.SaveAs("sample.xlsx")
End Sub
$vbLabelText   $csharpLabel

7. Read Excel Files In-Depth Tutorial

Dive in with further details and multiple projects and code examples if you want to learn more about how to Read Excel Files C# with this tutorial.


Tutorial Quick Access

Documentation related to Tutorial Quick Access

Investigate the API Reference

Documentation is provided for IronXL, featuring all namespaces, feature sets, methods fields, classes, and enums.

API Reference

Frequently Asked Questions

What is the purpose of using Excel in .NET Core applications?

Excel is used in .NET Core applications for efficient data management and manipulation. IronXL allows developers to programmatically load, edit, and save Excel files using C#, enhancing productivity and data handling capabilities.

How can I install the Excel library in a .NET Core project?

You can install the IronXL library in a .NET Core project by using the NuGet Package Manager with the command: dotnet add package IronXL.Excel. Alternatively, you can download the DLL file directly from the IronXL website.

What are the steps to load an Excel file in .NET Core?

To load an Excel file in .NET Core using IronXL, use the WorkBook.Load method. For example, WorkBook wb = WorkBook.Load("sample.xlsx"); will load the Excel workbook named 'sample.xlsx'.

Can I edit a range of cells in an Excel sheet using .NET Core?

Yes, with IronXL, you can edit a range of cells in an Excel sheet simultaneously. Use the syntax ws["A1:A9"].Value = "new value"; to assign a value to multiple cells, where ws is a WorkSheet object.

How do I handle user inputs when editing Excel files in .NET Core?

IronXL allows handling user inputs by capturing them through the console or a user interface, which can then be used to define the cell range and value for updates in the Excel spreadsheet.

What programming language is used for Excel manipulation in .NET Core?

C# is used for manipulating Excel files programmatically in .NET Core applications using the IronXL library.

Is there a tutorial for working with Excel files in .NET Core?

Yes, comprehensive tutorials on reading and manipulating Excel files using C# with IronXL are available. Additional resources and example projects can be found on the IronXL website.

What are the compatibility requirements for using the Excel library in .NET Core?

IronXL supports various versions of .NET Core. Detailed compatibility information can be found in the IronXL documentation on their website.

Where can I access the API documentation for the Excel library?

The API documentation for IronXL is available online, providing details on all namespaces, methods, and features. Visit the IronXL website to access this resource.

Regan Pun
Software Engineer
Regan graduated from the University of Reading, with a BA in Electronic Engineering. Before joining Iron Software, his previous job roles had him laser-focused on single tasks; and what he most enjoys at Iron Software is the spectrum of work he gets to undertake, whether it’s adding value to ...Read More