How to Import Excel Files in C#

IronXL Makes Excel Import Easier

Import data using the functions provided by the IronXL Excel library, which we'll be using in this tutorial. The software is available free for development. IronXL provides a comprehensive C# Excel API that simplifies working with Excel files without requiring Microsoft Office or Interop dependencies. This makes it ideal for server environments and cloud deployments.

Installation Methods

Install into your C# Project via DLL Download or navigate using the NuGet package. For detailed installation guidance, check out our getting started overview.

Install-Package IronXL.Excel

How to Tutorial

Basic WorkBook Loading Process

For our project needs today, we'll import Excel data into our C# application using the IronXL software installed in step 1. The library supports various Excel formats and provides intuitive methods for loading spreadsheets.

For step 2, we'll load our Excel WorkBook in our CSharp project by using the WorkBook.Load() function of IronXL. We pass the path of the Excel WorkBook as a string parameter in this function:

// Load Excel file
WorkBook wb = WorkBook.Load("Path");

// Load Excel file
WorkBook wb = WorkBook.Load("Path");

' Load Excel file
Dim wb As WorkBook = WorkBook.Load("Path")

The Excel file at the specified path will be loaded into wb. This method supports XLSX, XLS, CSV, TSV, and other common spreadsheet formats.

Accessing a Specific WorkSheet

Next, we need to access a specific WorkSheet of the Excel file whose data will be imported into the project. For this purpose, we can use the GetWorkSheet() function of IronXL, passing the sheet name as a string parameter to specify which sheet of the WorkBook to import. Learn more about managing worksheets in our comprehensive guide.

// Specify sheet name of Excel WorkBook
WorkSheet ws = wb.GetWorkSheet("SheetName");

// Specify sheet name of Excel WorkBook
WorkSheet ws = wb.GetWorkSheet("SheetName");

' Specify sheet name of Excel WorkBook
Dim ws As WorkSheet = wb.GetWorkSheet("SheetName")

The WorkSheet will be imported as ws, and wb is the WorkBook which we defined in the above code sample.

Alternative Methods to Access WorkSheets

The following alternative ways exist to import an Excel WorkSheet into the project. Each method provides flexibility depending on your specific use case:

// Import WorkSheet by various methods

// by sheet indexing
WorkSheet mySheet = wb.WorkSheets[SheetIndex];

// get default WorkSheet
WorkSheet defaultSheet = wb.DefaultWorkSheet;

// get first WorkSheet
WorkSheet firstSheet = wb.WorkSheets.First();

// for the first or default sheet
WorkSheet firstOrDefaultSheet = wb.WorkSheets.FirstOrDefault();

// Import WorkSheet by various methods

// by sheet indexing
WorkSheet mySheet = wb.WorkSheets[SheetIndex];

// get default WorkSheet
WorkSheet defaultSheet = wb.DefaultWorkSheet;

// get first WorkSheet
WorkSheet firstSheet = wb.WorkSheets.First();

// for the first or default sheet
WorkSheet firstOrDefaultSheet = wb.WorkSheets.FirstOrDefault();

' Import WorkSheet by various methods

' by sheet indexing
Dim mySheet As WorkSheet = wb.WorkSheets(SheetIndex)

' get default WorkSheet
Dim defaultSheet As WorkSheet = wb.DefaultWorkSheet

' get first WorkSheet
Dim firstSheet As WorkSheet = wb.WorkSheets.First()

' for the first or default sheet
Dim firstOrDefaultSheet As WorkSheet = wb.WorkSheets.FirstOrDefault()

Now, we can easily import any type of data from the specified Excel files. Let's explore all possible aspects for importing Excel file data in our project.

Basic Cell Import Method

This is the basic aspect of importing Excel file data into our project. IronXL provides multiple ways to access cell data, making it flexible for different scenarios.

For this purpose, we can use a cell addressing system to specify which cell data we need to import. It returns the value of a specific cell address from the Excel file:

var cellValue = ws["Cell Address"];

var cellValue = ws["Cell Address"];

Dim cellValue = ws("Cell Address")

Importing Data Using Row and Column Indexes

We can also import cell data from Excel files by using row and column indexes. This line of code returns the value of the specified row and column index. This approach is particularly useful when iterating through data programmatically:

var cellValueByIndex = ws.Rows[RowIndex].Columns[ColumnIndex];

var cellValueByIndex = ws.Rows[RowIndex].Columns[ColumnIndex];

Dim cellValueByIndex = ws.Rows(RowIndex).Columns(ColumnIndex)

Storing Imported Values in Variables

To assign imported cell values to variables, use this code. The ToString() method ensures compatibility with string variables, but you can also cast to other types as needed:

// Import Data by Cell Address
// by cell addressing
string val = ws["Cell Address"].ToString();

// by row and column indexing
string valWithIndexing = ws.Rows[RowIndex].Columns[ColumnIndex].Value.ToString();

// for numeric values
decimal numericValue = ws["B2"].DecimalValue;

// for date values
DateTime dateValue = ws["C2"].DateTimeValue;

// Import Data by Cell Address
// by cell addressing
string val = ws["Cell Address"].ToString();

// by row and column indexing
string valWithIndexing = ws.Rows[RowIndex].Columns[ColumnIndex].Value.ToString();

// for numeric values
decimal numericValue = ws["B2"].DecimalValue;

// for date values
DateTime dateValue = ws["C2"].DateTimeValue;

IRON VB CONVERTER ERROR developers@ironsoftware.com

In the above examples, the row and column index starts at 0. For more advanced cell operations, explore our guide on clearing cells and copying cells.

Range Function Syntax

To import data in a specific range from an Excel WorkBook, use the range function. Define the range by describing the starting and ending cell addresses. This returns all cell values within the specified range. For comprehensive range selection techniques, see our select range guide.

var rangeData = ws["Starting Cell Address:Ending Cell Address"];

var rangeData = ws["Starting Cell Address:Ending Cell Address"];

Dim rangeData = ws("Starting Cell Address:Ending Cell Address")

Complete Range Import Example

For more information about working with range in Excel files and learn more about pulling data in different methods. The following example demonstrates importing both individual cell values and ranges:

:path=/static-assets/excel/content-code-examples/how-to/csharp-import-excel-import.cs

using IronXL;
using System;

// Import Excel WorkBook
WorkBook wb = WorkBook.Load("sample.xlsx");

// Specify WorkSheet
WorkSheet ws = wb.GetWorkSheet("Sheet1");

// Import data of specific cell
string val = ws["A4"].Value.ToString();
Console.WriteLine("Import Value of A4 Cell address: {0}", val);

Console.WriteLine("import Values in Range From B3 To B9 :\n");

// Import data in specific range
foreach (var item in ws["B3:B9"])
{
    Console.WriteLine(item.Value.ToString());
}

Console.ReadKey();

IRON VB CONVERTER ERROR developers@ironsoftware.com

The above code displays the following output:

With the values of Excel file sample.xlsx as:

Available Aggregate Functions

Apply aggregate functions to Excel files and import the resulting data from these functions. IronXL provides built-in math functions that make data analysis straightforward. Here are examples of different functions and their usage:

• Sum()

  // To find the sum of a specific cell range
  var sum = ws["Starting Cell Address:Ending Cell Address"].Sum();

  // To find the sum of a specific cell range
  var sum = ws["Starting Cell Address:Ending Cell Address"].Sum();

  ' To find the sum of a specific cell range
  Dim sum = ws("Starting Cell Address:Ending Cell Address").Sum()

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• Average()

  // To find the average of a specific cell range
  var average = ws["Starting Cell Address:Ending Cell Address"].Avg();

  // To find the average of a specific cell range
  var average = ws["Starting Cell Address:Ending Cell Address"].Avg();

  ' To find the average of a specific cell range
  Dim average = ws("Starting Cell Address:Ending Cell Address").Avg()

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• Min()

  // To find the minimum in a specific cell range
  var minimum = ws["Starting Cell Address:Ending Cell Address"].Min();

  // To find the minimum in a specific cell range
  var minimum = ws["Starting Cell Address:Ending Cell Address"].Min();

  ' To find the minimum in a specific cell range
  Dim minimum = ws("Starting Cell Address:Ending Cell Address").Min()

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• Max()

  // To find the maximum in a specific cell range
  var maximum = ws["Starting Cell Address:Ending Cell Address"].Max();

  // To find the maximum in a specific cell range
  var maximum = ws["Starting Cell Address:Ending Cell Address"].Max();

  ' To find the maximum in a specific cell range
  Dim maximum = ws("Starting Cell Address:Ending Cell Address").Max()

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Using Multiple Aggregate Functions Together

Read more about working with aggregate functions in Excel for C# and learn more about pulling data in different methods. These functions are particularly useful for generating summary statistics or validating imported data.

See an example of importing Excel file data by applying these functions:

:path=/static-assets/excel/content-code-examples/how-to/csharp-import-excel-math-functions.cs

using IronXL;
using System;

// Import Excel file
WorkBook wb = WorkBook.Load("sample.xlsx");

// Specify WorkSheet
WorkSheet ws = wb.GetWorkSheet("Sheet1");

// Import Excel file data by applying aggregate functions
decimal sum = ws["D2:D9"].Sum();
decimal avg = ws["D2:D9"].Avg();
decimal min = ws["D2:D9"].Min();
decimal max = ws["D2:D9"].Max();

Console.WriteLine("Sum From D2 To D9: {0}", sum);
Console.WriteLine("Avg From D2 To D9: {0}", avg);
Console.WriteLine("Min From D2 To D9: {0}", min);
Console.WriteLine("Max From D2 To D9: {0}", max);

Console.ReadKey();

IRON VB CONVERTER ERROR developers@ironsoftware.com

The above code gives us this output:

And our file sample.xlsx contains these values:

The ToDataSet Method

To import complete Excel file data into a C# project, first parse the loaded WorkBook into a DataSet. This way, the complete Excel data imports into the DataSet, and WorkSheets in Excel files become DataTables within that DataSet. This approach is particularly useful for database operations or when working with data-bound controls. Learn more about importing and exporting as DataSet.

// Import WorkBook into DataSet
DataSet ds = wb.ToDataSet();

// Import WorkBook into DataSet
DataSet ds = wb.ToDataSet();

' Import WorkBook into DataSet
Dim ds As DataSet = wb.ToDataSet()

This imports our specified WorkSheet into a DataSet for use according to requirements. This method is especially powerful when working with multiple sheets simultaneously or when integrating Excel data with ADO.NET operations.

Handling Column Headers

Often, the first row of an Excel file serves as column names. In this case, make the first row DataTable column names. Set the boolean parameter of the ToDataSet() function of IronXL as follows:

// Import WorkBook into DataSet with first row as ColumnNames
DataSet ds = wb.ToDataSet(true);

// Import WorkBook into DataSet with first row as ColumnNames
DataSet ds = wb.ToDataSet(true);

' Import WorkBook into DataSet with first row as ColumnNames
Dim ds As DataSet = wb.ToDataSet(True)

This makes the first row of the Excel file DataTable column names, which is essential for maintaining data structure integrity when working with structured Excel data.

Complete DataSet Import Example

See a complete example of importing Excel data into a DataSet and using the first row of an Excel WorkSheet as DataTable column names:

:path=/static-assets/excel/content-code-examples/how-to/csharp-import-excel-dataset.cs

using IronXL;
using System;
using System.Data;

WorkBook wb = WorkBook.Load("sample.xlsx");
WorkSheet ws = wb.GetWorkSheet("Sheet1");

// Import Excel data into a DataSet
DataSet ds = wb.ToDataSet(true);

Console.WriteLine("Excel file data imported to dataset successfully.");
Console.ReadKey();

IRON VB CONVERTER ERROR developers@ironsoftware.com

Working with Excel Dataset and DataTable functions can be complex, but we have more examples available for incorporating file data into your C# project. For advanced scenarios, consider exploring our guides on Excel to SQL via DataTable and loading Excel from SQL database.

Library Quick Access

Explore the IronXL Reference

Learn more about pulling Excel data via cells, range, datasets and datatables in our full documentation API Reference for IronXL.

Explore the IronXL Reference