I’m using the following method to transform XML data into HTML using an XSLT stylesheet in C#. However, I’m encountering OutOfMemoryException when processing large XML data. How can I optimize this method to handle large XML and XSLT data without running out of memory?

private static string TransformXMLToHTML(string xsltString, string xmlData) {

XslCompiledTransform transform = new XslCompiledTransform();

using (XmlReader reader = XmlReader.Create(new StringReader(xsltString)))
{
    transform.Load(reader);
}

UTF8StringWriter results = new UTF8StringWriter();

using (XmlReader reader = XmlReader.Create(new StringReader(xmlData)))
{
    transform.Transform(reader, null, results);
}

return results.ToString(); }

UTF8StringWriter:

public class UTF8StringWriter : StringWriter
{
    public UTF8StringWriter() { }
    public UTF8StringWriter(IFormatProvider formatProvider) : base(formatProvider) { }
    public UTF8StringWriter(StringBuilder sb) : base(sb) { }
    public UTF8StringWriter(StringBuilder sb, IFormatProvider formatProvider) : base(sb, formatProvider) { }

    public override Encoding Encoding
    {
        get
        {
            return Encoding.UTF8;
        }
    }
}

Note: I have referenced other similar questions, few suggested to use file stream but I can’t use it here as it will introduce handling file related operations which we can’t apply to our entire code base