SwiftExcel

Overview

Lightweight, extremely fast and memory efficient Excel output library for .NET and .NET Core applications. Build your Excel reports in fraction of seconds with no memory footprint thanks to skipping XML serialization and streaming data directly to the file.

Installation

SwiftExcel is available as a NuGet package. You can install it using the NuGet Package Console window:

PM> Install-Package SwiftExcel

Usage

Fill excel document with test data 100 rows x 10 columns

using (var ew = new ExcelWriter("C:\\temp\\test.xlsx"))
{
    for (var row = 1; row <= 100; row++)
    {
        for (var col = 1; col <= 10; col++)
        {
            ew.Write($"row:{row}-col:{col}", col, row);
        }
    }
}

Set custom sheet name and define columns width

var sheet = new Sheet
{
    Name = "Monthly Report", 
    ColumnsWidth = new List<double> { 10, 12, 8, 8, 35 }
};

var ew = new ExcelWriter("C:\\temp\\test.xlsx", sheet);

Using formulas. Output 20 values and calculate average, count, max and sum

using (var ew = new ExcelWriter("C:\\temp\\test.xlsx"))
{
    for (var row = 1; row <= 20; row++)
    {
        ew.Write(row.ToString(), 1, row, DataType.Number);
    }

    ew.WriteFormula(FormulaType.Average, 1, 22, 1, 1, 20);
    ew.WriteFormula(FormulaType.Count, 1, 23, 1, 1, 20);
    ew.WriteFormula(FormulaType.Max, 1, 24, 1, 1, 20);
    ew.WriteFormula(FormulaType.Sum, 1, 25, 1, 1, 20);
}

Performance

SwiftExcel has incredible performance due to ignoring XML serialization and streaming data directly to the file. Below is a performance test creating a document with 100 000 rows and 100 columns compared to other popular Excel output libraries on Nuget.

	Execution Time	Memory Usage
SwiftExcel	6.1 sec	19 mb
FastExcel	31.1 sec	3200 mb
EPPlus	44.2 sec	2900 mb
Syncfusion.XlsIO	73.3 sec	2700 mb
IronXL.Excel	306.8 sec	7700 mb
Microsoft Interop Excel	>3 hours	27 mb

SwiftExcel.Pro

Check out the .Pro version for advanced features like working with multiple sheets or applying custom styles.