C# Read XLSX File

When working with various Excel formats, it often requires reading the data and manipulating it programmatically. In the following tutorial, we will learn how to read data from an Excel spreadsheet in C# using a convenient tool, IronXL.

Read .XLSX Files C#

  • Get IronXL for your project
  • Load a WorkBook
  • Access data from a WorkSheet
  • Apply functions like Sum, Min, & Max
  • Read a WorkSheet as a DataTable, DataSet, and more
How To Work related to C# Read XLSX File

Step 1

1. Get IronXL for Your Project

Use IronXL in your project for a simple way to work with Excel file formats in C#. You can either install IronXL via direct download or alternatively you can use NuGet Install for Visual Studio. The software is free for development.

Install-Package IronXL.Excel

How to Tutorial

2. Load WorkBook

WorkBook is the class of IronXL whose object provides full access to the Excel file and its whole functions. For example, if we want to access an Excel file, we'd use the code:

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-load-workbook.cs
using IronXL;

// Load the workbook
WorkBook workBook = WorkBook.Load("sample.xlsx"); // Excel file path
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In the above code, the WorkBook.Load() function loads sample.xlsx into workBook. Any type of function can be performed on workBook by accessing the specific WorkSheet of an Excel file.


3. Access Specific WorkSheet

To access a specific WorkSheet of an Excel file, IronXL provides the WorkSheet class. It can be used in a few different ways:

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-get-worksheet.cs
using IronXL;

// Access sheet by name
WorkSheet workSheet = workBook.GetWorkSheet("Sheet1");
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workBook is the WorkBook that is declared in the above portion.

OR

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-worksheet-index.cs
using IronXL;

// Access sheet by index
WorkSheet workSheet = workBook.WorkSheets[0];
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OR

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-default-worksheet.cs
using IronXL;

// Access the default worksheet
WorkSheet workSheet = workBook.DefaultWorkSheet;
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OR

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-first-worksheet.cs
using IronXL;
using System.Linq;

// Access the first worksheet
WorkSheet workSheet = workBook.WorkSheets.First();
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OR

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-first-or-default-worksheet.cs
using IronXL;
using System.Linq;

// Access the first or default worksheet
WorkSheet workSheet = workBook.WorkSheets.FirstOrDefault();
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After getting ExcelSheet workSheet, you can get any type of data from it and perform all Excel functions on it.


4. Access Data from WorkSheet

Data can be accessed from ExcelSheet workSheet with this process:

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-get-data.cs
using IronXL;

// Accessing data as a string
string dataString = workSheet["A1"].ToString();

// Accessing data as an integer
int dataInt = workSheet["B1"].Int32Value;
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It is also possible to get data from multiple cells of a specific column.

foreach (var cell in workSheet["A2:A10"])
{
    Console.WriteLine("Value is: {0}", cell.Text);
}
foreach (var cell in workSheet["A2:A10"])
{
    Console.WriteLine("Value is: {0}", cell.Text);
}
For Each cell In workSheet("A2:A10")
	Console.WriteLine("Value is: {0}", cell.Text)
Next cell
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This will display the values from cell A2 to A10.

A complete code example of the specifics above is provided here.

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-log-data.cs
using IronXL;
using System;

// Load an Excel file
WorkBook workBook = WorkBook.Load("sample.xlsx");
WorkSheet workSheet = workBook.GetWorkSheet("Sheet1");

// Specify the range
foreach (var cell in workSheet["B2:B10"])
{
    Console.WriteLine("Value is: {0}", cell.Text);
}
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It will display the following result:

Doc3 Input1 related to 4. Access Data from WorkSheet

With the Excel file Sample.xlsx :

Doc3 1 related to 4. Access Data from WorkSheet

We can see how effortless it is to use Excel file data in your project using these methodologies.


5. Perform Functions on Data

It is very straightforward to access filtered data from an Excel WorkSheet by applying aggregate functions like Sum, Min, or Max using the following code:

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-aggregate-function.cs
using IronXL;

// Apply aggregate functions
decimal sum = workSheet["G2:G10"].Sum(); // Sum of cells from G2 to G10
decimal min = workSheet["G2:G10"].Min(); // Minimum value in cells from G2 to G10
decimal max = workSheet["G2:G10"].Max(); // Maximum value in cells from G2 to G10
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If you want more details, check out our in-depth tutorial on How to Write C# Excel Files with specifics on aggregate functions.

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-min-max.cs
using IronXL;
using System;

// Load the Excel workbook
WorkBook workBook = WorkBook.Load("sample.xlsx");

// Get the specified WorkSheet
WorkSheet workSheet = workBook.GetWorkSheet("Sheet1");

// Calculate sum, minimum, and maximum for a range of cells
decimal sum = workSheet["G2:G10"].Sum();
decimal min = workSheet["G2:G10"].Min();
decimal max = workSheet["G2:G10"].Max();

// Output results
Console.WriteLine("Sum is: {0}", sum);
Console.WriteLine("Min is: {0}", min);
Console.WriteLine("Max is: {0}", max);
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This code will display the following output:

Doc3 Output2 related to 5. Perform Functions on Data

And this is how the Excel file Sample.xlsx will look:

Doc3 2 related to 5. Perform Functions on Data

6. Read Excel WorkSheet as DataTable

Using IronXL, it is very easy to operate with an Excel WorkSheet as a DataTable.

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-datatable.cs
using IronXL;
using System.Data;

// Convert worksheet to DataTable
DataTable dt = workSheet.ToDataTable();
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If we want to use the first row of ExcelSheet as DataTable ColumnName then:

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-datatable-header.cs
using IronXL;
using System.Data;

// Convert worksheet to DataTable with the first row as column names
DataTable dt = workSheet.ToDataTable(true);
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Thus, the Boolean parameter of ToDataTable() sets the first row as the column names of your DataTable. By default, its value is False.

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-print-datatable.cs
using IronXL;
using System;
using System.Data;

// Load the Excel workbook
WorkBook workBook = WorkBook.Load("sample.xlsx");

// Get the specified WorkSheet
WorkSheet workSheet = workBook.GetWorkSheet("Sheet1");

// Convert WorkSheet to DataTable
DataTable dt = workSheet.ToDataTable(true); // Use first row as column names

// Iterate through rows and columns and display data
foreach (DataRow row in dt.Rows) // Access rows
{
    for (int i = 0; i < dt.Columns.Count; i++) // Access columns of corresponding row
    {
        Console.Write(row[i] + " ");
    }
    Console.WriteLine();
}
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Using the above code, every cell value of the WorkSheet can be accessed and used as required.


7. Read Excel File as DataSet

IronXL provides a very simple function to use a complete Excel file (WorkBook) as a DataSet. Use the ToDataSet method to turn the whole workbook into DataSet. In this example, we will see how to use the Excel file as a DataSet.

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-file-excel-to-dataset.cs
using IronXL;
using System;
using System.Data;

// Load the Excel workbook
WorkBook workBook = WorkBook.Load("sample.xlsx");

// Convert the WorkBook to a DataSet
DataSet ds = workBook.ToDataSet();

// Iterate through tables in the DataSet and display table names
foreach (DataTable dt in ds.Tables)
{
    Console.WriteLine(dt.TableName);
}
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The output of the above code will look like this:

Doc10 Output2 related to 7. Read Excel File as DataSet

And the Excel file Sample.xlsx will look like this:

Doc10 2 related to 7. Read Excel File as DataSet

In the above example, we see that we can easily parse an Excel file into a DataSet and employ it with every WorkSheet of an Excel file as a DataTable. Dive more into how to parse Excel as a DataSet here featuring code examples.

Let's see one more example of how to access each cell value of all ExcelSheets. Here, we can access each cell value of every WorkSheet of an Excel file.

:path=/static-assets/excel/content-code-examples/how-to/c-sharp-read-xlsx-all-excel-sheets.cs
// THIS CODE SNIPPET IS NOT AVAILABLE!
' THIS CODE SNIPPET IS NOT AVAILABLE!
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Using the above example, it is very convenient to access each cell value of every WorkSheet of an Excel file.

For more on how to Read Excel Files Without Interop check out the code here.


Tutorial Quick Access

API Reference for IronXL

Read more about IronXL's features, classes, method fields, namespaces, and enums in the documentation.

API Reference for IronXL
Documentation related to Tutorial Quick Access

Frequently Asked Questions

How can I read an XLSX file in C# without using Interop?

To read an XLSX file in C# without using Interop, you can use the IronXL library. After installing IronXL, you can load an Excel workbook using WorkBook.Load() method and access its contents.

How do I load an Excel Workbook in C#?

You can load an Excel Workbook in C# using IronXL by calling WorkBook.Load('yourfile.xlsx'), which opens the specified file for manipulation.

What methods are available for accessing worksheets in an Excel file?

In IronXL, you can access worksheets using GetWorkSheet method by name or index, as well as properties like DefaultWorkSheet or First.

How can I manipulate data in an Excel worksheet using C#?

You can manipulate data in an Excel worksheet using IronXL by accessing cell values with syntax like ws['A1'].ToString() for strings or ws['B1'].Int32Value for integers, and applying functions such as Sum on cell ranges.

Can I perform aggregate operations on Excel data in C#?

Yes, IronXL allows performing aggregate operations on Excel data in C# using methods like Sum(), Min(), and Max() on specified cell ranges.

Is it possible to convert an Excel worksheet to a DataTable?

Yes, you can convert an Excel worksheet to a DataTable in C# using IronXL's ToDataTable() method, with an option to treat the first row as column names.

How can you use an Excel workbook as a DataSet in C#?

With IronXL, an Excel workbook can be utilized as a DataSet by calling the ToDataSet() method, enabling comprehensive data manipulation.

What are the advantages of using a library for Excel file manipulation in C#?

Using IronXL for Excel file manipulation in C# offers simplicity and efficiency, supporting various Excel formats, enabling operations on data, and providing features like converting worksheets to DataTables.

Where can I find additional resources for using IronXL?

You can find more resources and documentation on IronXL's API Reference page, which includes detailed information on its features, classes, and methods.

Curtis Chau
Technical Writer

Curtis Chau holds a Bachelor’s degree in Computer Science (Carleton University) and specializes in front-end development with expertise in Node.js, TypeScript, JavaScript, and React. Passionate about crafting intuitive and aesthetically pleasing user interfaces, Curtis enjoys working with modern frameworks and creating well-structured, visually appealing manuals.

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