Read Excel in C# with Simple Code

#csharp #tutorial #dotnet

【Introduction】

In daily C# development, processing Excel data is a requirement almost every developer encounters. Whether it’s importing user data, generating reports, or conducting data analysis, Excel plays an indispensable role. However, traditional C# Excel reading methods—such as Microsoft.Office.Interop.Excel based on COM Interop—are often plagued by pain points like performance bottlenecks, environment dependencies, and complex deployment.

This article introduces how to implement a simple, efficient Excel reading solution using Spire.XLS for .NET, with no Office dependencies required.

I. 🔧 Environment Preparation

Step 1: Create a VS2022 Console Project

File → New → Project → Console App template

Step 2: Install via NuGet:

▸ Graphic Interface: Right-click the project → Manage NuGet Packages → Search for "FreeSpire.XLS"

▸ Command Line:

install-package Spire.XLS

or install the free version: install-package FreeSpire.XLS

Verify successful installation: Check that the Spire.XLS assembly appears in the project references.

II. ▶️ Read Excel Files in C# Quickly

Import the namespace:

using Spire.Xls;

Read data:

// Load Excel (supports both XLS and XLSX formats)
Workbook wb = new Workbook();
wb.LoadFromFile("Sample.xlsx");

// Read cell data (2 methods)
Worksheet sheet = wb.Worksheets[0];
Console.WriteLine(sheet.Range["A1"].Value);      // Locate by column name
Console.WriteLine(sheet.Range[2, 1].Value);     // Locate by row and column numbers

❗️ Common Pitfall: Indexing
When reading data by row and column numbers, the indexes start from 1.

Read Data from an Entire Excel Worksheet

Read all data via loops:

using Spire.Xls;

namespace ReadExcelData
{
    class Program
    {
        static void Main(string[] args)
        {
            // Load the Excel document
            Workbook wb = new Workbook();
            wb.LoadFromFile("Sample.xlsx");

            // Get the first worksheet
            Worksheet sheet = wb.Worksheets[0];

            // Get the data range in the worksheet
            CellRange locatedRange = sheet.AllocatedRange;

            // Iterate through rows and columns in the range
            for (int i = 0; i < locatedRange.Rows.Length; i++)
            {
                for (int j = 0; j < locatedRange.Rows[i].ColumnCount; j++)
                {
                    // Read cell data
                    Console.Write(locatedRange[i + 1, j + 1].Value + "  ");
                }
                Console.WriteLine();
            }
        }
    }
}

III. 🧩 Read Excel Formulas

The Value property returns the formula directly. To read the calculated result of the formula:

foreach (CellRange cell in sheet.AllocatedRange)
{
    if (cell.HasFormula)
    {
        // Get the original formula
        string formula = cell.Formula;

        // Get the calculated result of the formula (use FormulaValue directly)
        string formulaResult = cell.FormulaValue.ToString();
    }
}