How to Convert Excel to HTML in C#

Exporting Excel data to HTML format is essential when displaying spreadsheet content in browsers, email templates, or web applications. This guide shows how to convert an Excel workbook to HTML using Aspose.Cells for .NET.

When to Use Excel to HTML Conversion

Generate previews of Excel data on websites
Enable web-based spreadsheet viewing
Embed tabular data in CMS or blogs

Step-by-Step Guide

Step 1: Install Aspose.Cells for .NET

dotnet add package Aspose.Cells

Step 2: Load the Workbook

Workbook workbook = new Workbook("path/to/excel.xlsx");

Step 3: Set HTML Save Options (Optional)

HtmlSaveOptions options = new HtmlSaveOptions(SaveFormat.Html);

Step 4: Export Excel to HTML File

workbook.Save("path/to/output.html", options);

Step 5: Save to a MemoryStream Instead of a File

using (MemoryStream outputStream = new MemoryStream())
{
    workbook.Save(outputStream, SaveFormat.Html);
    outputStream.Position = 0;

    // Use the stream in a web response, save to disk, etc.
}

Complete Code Example

using System;
using System.IO;
using Aspose.Cells;

class Program
{
    static void Main()
    {
        Workbook workbook = new Workbook("input.xlsx");

        // Option 1: Save to HTML file
        HtmlSaveOptions options = new HtmlSaveOptions(SaveFormat.Html);
        workbook.Save("output.html", options);

        // Option 2: Save to stream for web applications
        using (MemoryStream stream = new MemoryStream())
        {
            workbook.Save(stream, SaveFormat.Html);
            stream.Position = 0;
            // Use the stream as needed (e.g., send in API response)
        }

        Console.WriteLine("Excel exported to HTML.");
    }
}

Tips and Best Practices

Tip	Description
Use `HtmlSaveOptions`	Fine-tune output HTML structure, character encoding, or image embedding
Save to stream	Useful for APIs or serverless functions
Preserve styling	Aspose.Cells ensures most styling and layout elements are retained