XSitemaps

SEO (= Search Engine Optimization) is very important to improve the page views of your website. Sitemaps are defined in a simple XML-formatted file that can be read by search engines to more accurately crawl your site. And also Sitemaps are widely supported by many companies, including Google, Yahoo!, and Microsoft. See sitemaps.org for more details.

This library provides a simple and easy to use sitemap.xml serializer.

Supported features

• Sitemap file serialization
  • Google-specific extensions (currently, image only)
• SitemapIndex file serialization
• Split files according to the number of URLs
• Controllable indent
• GZIP compression

Support platform

• .NET Standard 2.0+
• .NET 8+

How to use

Create Sitemap.xml

//--- Create Sitemaps
var modifiedAt = new DateTimeOffset(2026, 1, 2, 12, 34, 56, TimeSpan.FromHours(9));
var urls
    = new SitemapUrl[]
    {
        new("https://blog.xin9le.net"),
        new("https://blog.xin9le.net/entry/rx-intro", modifiedAt, ChangeFrequency.Daily, priority: 0.8),
        new("https://blog.xin9le.net/entry/async-method-intro", frequency: ChangeFrequency.Weekly),
        new("https://example.com/sample1.html", google: new
        (
            images: [
                new("https://example.com/image.jpg"),
                new("https://example.com/photo.jpg"),
            ]
        )),
        new("https://example.com/sample2.html", google: new
        (
            images: [
                new("https://example.com/picture.jpg"),
            ]
        )),
    };
var sitemaps = Sitemap.Create(urls, maxUrlCount: 3);

//--- Output to files
foreach (var (index, sitemap) in sitemaps.Index())
{
    var desktop = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
    var path = Path.Combine(desktop, $"sitemap{index}.xml");
    using (var stream = new FileStream(path, FileMode.CreateNew))
    {
        var options = new SerializeOptions
        {
            EnableIndent = true,
            EnableGzipCompression = false,
        };
        SitemapSerializer.Serialize(stream, sitemap, options);
    }
}

//--- sitemap0.xml
<?xml version="1.0" encoding="utf-8"?>
<urlset xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd" xmlns:image="http://www.google.com/schemas/sitemap-image/1.1" xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>https://blog.xin9le.net</loc>
  </url>
  <url>
    <loc>https://blog.xin9le.net/entry/rx-intro</loc>
    <lastmod>2026-01-02T12:34:56.0000000+09:00</lastmod>
    <changefreq>daily</changefreq>
    <priority>0.8</priority>
  </url>
  <url>
    <loc>https://blog.xin9le.net/entry/async-method-intro</loc>
    <changefreq>weekly</changefreq>
  </url>
</urlset>

//--- sitemap1.xml
<?xml version="1.0" encoding="utf-8"?>
<urlset xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd" xmlns:image="http://www.google.com/schemas/sitemap-image/1.1" xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>https://example.com/sample1.html</loc>
    <image:image>
      <image:loc>https://example.com/image.jpg</image:loc>
    </image:image>
    <image:image>
      <image:loc>https://example.com/photo.jpg</image:loc>
    </image:image>
  </url>
  <url>
    <loc>https://example.com/sample2.html</loc>
    <image:image>
      <image:loc>https://example.com/picture.jpg</image:loc>
    </image:image>
  </url>
</urlset>

Create SitemapIndex.xml

//--- Create SitemapIndex
var modifiedAt = new DateTimeOffset(2026, 1, 2, 12, 34, 56, TimeSpan.FromHours(9));
var info = new SitemapInfo[]
{
    new("https://example.com/sitemap0.xml", modifiedAt),
    new("https://example.com/sitemap1.xml"),
};
var index = new SitemapIndex(info);

//--- Output to file
var desktop = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
var path = Path.Combine(desktop, $"sitemapindex.xml");
using (var stream = new FileStream(path, FileMode.CreateNew))
{
    var options = new SerializeOptions
    {
        EnableIndent = true,
        EnableGzipCompression = false,
    };
    SitemapSerializer.Serialize(stream, index, options);
}

<?xml version="1.0" encoding="utf-8"?>
<sitemapindex xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/siteindex.xsd" xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <sitemap>
    <loc>https://example.com/sitemap0.xml</loc>
    <lastmod>2026-01-02T12:34:56.0000000+09:00</lastmod>
  </sitemap>
  <sitemap>
    <loc>https://example.com/sitemap1.xml</loc>
  </sitemap>
</sitemapindex>

Installation

Getting started from downloading NuGet package.

dotnet add package XSitemaps

License

This library is provided under MIT License.

Author

Takaaki Suzuki (a.k.a @xin9le) is software developer in Japan who awarded Microsoft MVP for Developer Technologies (C#) since July 2012.