1. IronXL
2. How-Tos
3. Excel Add in C#

C# Excel Add in (Code Example Tutorial)

When developing applications, you need to be able to manage data without Excel spreadsheets but still be able to communicate with the files. For example, you may need to insert new rows or columns in an existing Excel Spreadsheet programmatically. Using the functions for the umbrella concept "Excel: Add" in C#, we can add all these and more. See the examples below.

Step 1

1. Download the IronXL Excel Library

To access the functions to add rows and columns in Excel, first we need to download the IronXL Excel Library. This is free for development in your project. Download the DLL directly or you can use the NuGet install method.

Install-Package IronXL.Excel

How to Tutorial

2. Excel Add Row in C#

Now that we have installed IronXL, it will be easy to insert new rows and columns in existing Excel Spreadsheets using C# programming.

First, access your Excel SpreadSheet and specify the WorkSheet where new rows or columns need to be added.

2.1. Add Row in Last Position

In our first example, we'll show how to add the new row in the last position.

Suppose that our Excel file is named sample.xlsx, and has 5 columns from A to E. Using the following method we can add new row:

/**
Add Row Last Position
anchor-add-row-in-last-position
**/
using IronXL;
static void Main(string [] args)
{
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");
    int i = ws.Rows.Count() + 1;
    ws ["A" + i].Value = "New Row";
    ws ["B" + i].Value = "New Row";
    ws ["C" + i].Value = "New Row";
    ws ["D" + i].Value = "New Row";
    ws ["E" + i].Value = "New Row";
    wb.SaveAs("sample.xlsx");
}

/**
Add Row Last Position
anchor-add-row-in-last-position
**/
using IronXL;
static void Main(string [] args)
{
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");
    int i = ws.Rows.Count() + 1;
    ws ["A" + i].Value = "New Row";
    ws ["B" + i].Value = "New Row";
    ws ["C" + i].Value = "New Row";
    ws ["D" + i].Value = "New Row";
    ws ["E" + i].Value = "New Row";
    wb.SaveAs("sample.xlsx");
}

'''
'''Add Row Last Position
'''anchor-add-row-in-last-position
'''*
Imports IronXL
Shared Sub Main(ByVal args() As String)
	Dim wb As WorkBook = WorkBook.Load("sample.xlsx")
	Dim ws As WorkSheet = wb.GetWorkSheet("Sheet1")
	Dim i As Integer = ws.Rows.Count() + 1
	ws ("A" & i).Value = "New Row"
	ws ("B" & i).Value = "New Row"
	ws ("C" & i).Value = "New Row"
	ws ("D" & i).Value = "New Row"
	ws ("E" & i).Value = "New Row"
	wb.SaveAs("sample.xlsx")
End Sub

This will create a new row in the last position with value New Row in the Excel Spreadsheet sample.xlsx.

2.2. Add Row in First Position

It is also very simple to add a new row in the first position of the Excel SpreadSheet.

For this purpose, firstly we will move all existing rows into the next rows, so that the first row slot is available for us to add.

Let's see the example for how to add a new row in the first position of the Excel SpreadSheet.

/**
Add Row First Position
anchor-add-row-in-first-position
**/
using IronXL;
static void Main(string [] args)
{
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");
    int j = ws.Rows.Count() + 1;
    for (int i = 1; i <= ws.Rows.Count(); i++)
    {
        if (j == 0) 
        {
            ws.Rows [0].Value = "new row"; 
            break; 
        };
        ws ["A" + (j + 1)].Value = ws ["A" + j].Value; 
        ws ["B" + (j + 1)].Value = ws ["B" + j].Value;
        ws ["C" + (j + 1)].Value = ws ["C" + j].Value;
        ws ["D" + (j + 1)].Value = ws ["D" + j].Value;
        ws ["E" + (j + 1)].Value = ws ["E" + j].Value;
        j = j - 1;
    }
 wb.SaveAs("sample.xlsx"); 
}

/**
Add Row First Position
anchor-add-row-in-first-position
**/
using IronXL;
static void Main(string [] args)
{
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");
    int j = ws.Rows.Count() + 1;
    for (int i = 1; i <= ws.Rows.Count(); i++)
    {
        if (j == 0) 
        {
            ws.Rows [0].Value = "new row"; 
            break; 
        };
        ws ["A" + (j + 1)].Value = ws ["A" + j].Value; 
        ws ["B" + (j + 1)].Value = ws ["B" + j].Value;
        ws ["C" + (j + 1)].Value = ws ["C" + j].Value;
        ws ["D" + (j + 1)].Value = ws ["D" + j].Value;
        ws ["E" + (j + 1)].Value = ws ["E" + j].Value;
        j = j - 1;
    }
 wb.SaveAs("sample.xlsx"); 
}

'''
'''Add Row First Position
'''anchor-add-row-in-first-position
'''*
Imports IronXL
Shared Sub Main(ByVal args() As String)
	Dim wb As WorkBook = WorkBook.Load("sample.xlsx")
	Dim ws As WorkSheet = wb.GetWorkSheet("Sheet1")
	Dim j As Integer = ws.Rows.Count() + 1
	For i As Integer = 1 To ws.Rows.Count()
		If j = 0 Then
			ws.Rows (0).Value = "new row"
			Exit For
		End If
		ws ("A" & (j + 1)).Value = ws ("A" & j).Value
		ws ("B" & (j + 1)).Value = ws ("B" & j).Value
		ws ("C" & (j + 1)).Value = ws ("C" & j).Value
		ws ("D" & (j + 1)).Value = ws ("D" & j).Value
		ws ("E" & (j + 1)).Value = ws ("E" & j).Value
		j = j - 1
	Next i
 wb.SaveAs("sample.xlsx")
End Sub

Let's compare the changes done by the above code in our sample.xlsx document.

Before	After

Here we can see that before, the sample.xlsx file had 10 rows. With the new row added in the first position, it 11 became 11 rows.

2.3. Add Row in First with Column Header

In the case that we have the first column as a header name, then we can change the loop break condition at row 0, and have the new row added at position 1.

3. Excel Add Column in C#

It is also to add a new column in an existing Excel SpreadSheet for our C# project.

Suppose that we have 5 columns in our Excel SpreadSheet called sample.xlsx, from A to E, and we want to add a new column in the first position, A. See the code sample below.

/**
Add Column 
anchor-excel-add-column-in-c-num
**/
using IronXL;
static void Main(string [] args)
{  
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");
    for (int i = 1; i <= ws.Rows.Count(); i++)
    {
        ws ["F" + i].Value = ws ["E" + i].Value;
        ws ["E" + i].Value = ws ["D" + i].Value;
        ws ["D" + i].Value = ws ["C" + i].Value;
        ws ["C" + i].Value = ws ["B" + i].Value;
        ws ["B" + i].Value = ws ["A" + i].Value;
        ws ["A" + i].Value = "New Column Added";
    }
    wb.SaveAs("sample.xlsx");
}

/**
Add Column 
anchor-excel-add-column-in-c-num
**/
using IronXL;
static void Main(string [] args)
{  
    WorkBook wb = WorkBook.Load("sample.xlsx");
    WorkSheet ws = wb.GetWorkSheet("Sheet1");
    for (int i = 1; i <= ws.Rows.Count(); i++)
    {
        ws ["F" + i].Value = ws ["E" + i].Value;
        ws ["E" + i].Value = ws ["D" + i].Value;
        ws ["D" + i].Value = ws ["C" + i].Value;
        ws ["C" + i].Value = ws ["B" + i].Value;
        ws ["B" + i].Value = ws ["A" + i].Value;
        ws ["A" + i].Value = "New Column Added";
    }
    wb.SaveAs("sample.xlsx");
}

'''
'''Add Column 
'''anchor-excel-add-column-in-c-num
'''*
Imports IronXL
Shared Sub Main(ByVal args() As String)
	Dim wb As WorkBook = WorkBook.Load("sample.xlsx")
	Dim ws As WorkSheet = wb.GetWorkSheet("Sheet1")
	For i As Integer = 1 To ws.Rows.Count()
		ws ("F" & i).Value = ws ("E" & i).Value
		ws ("E" & i).Value = ws ("D" & i).Value
		ws ("D" & i).Value = ws ("C" & i).Value
		ws ("C" & i).Value = ws ("B" & i).Value
		ws ("B" & i).Value = ws ("A" & i).Value
		ws ("A" & i).Value = "New Column Added"
	Next i
	wb.SaveAs("sample.xlsx")
End Sub

Let's view the changes done by the above code in sample.xlsx:

Before	After

We can see that new column was added in first position A, and the rest were pushed back, so now we have a total of 6 columns from A to F.

Library Quick Access

Read the IronXL Documentation

Read the documentation for IronXL for more functions and information on adding rows, columns, and other Excel C# functionality.

Read the IronXL Documentation

Chaknith Bin

Software Engineer

 LinkedIn

Chaknith works on IronXL and IronBarcode. He has deep expertise in C# and .NET, helping improve the software and support customers. His insights from user interactions contribute to better products, documentation, and overall experience.