HtmlSaveOptions.ImageOptions

public ImageOrPrintOptions ImageOptions { get; }

// Called: ImageOrPrintOptions imageOptions = options.ImageOptions;
public void HtmlSaveOptions_Property_ImageOptions()
{
    Workbook wb = new Workbook(Constants.HtmlPath + "example.xlsx");
    HtmlSaveOptions options = new HtmlSaveOptions();
    options.ExportPrintAreaOnly = true;
    options.ExportImagesAsBase64 = true;
    ImageOrPrintOptions imageOptions = options.ImageOptions;
    imageOptions.ImageType = ImageType.Svg;
    wb.Save(_destFilesPath + "example.html", options);

    string dir = _destFilesPath + "CELLSJAVA-44534_files";
    DirectoryInfo dirInfo = new DirectoryInfo(dir);

    foreach (FileInfo fileInfo in dirInfo.GetFiles())
    {
        if (fileInfo.Extension == ".htm" && fileInfo.Name.IndexOf("sheet") > -1)
        {
            string content = File.ReadAllText(fileInfo.FullName);
            Assert.IsTrue(content.IndexOf("<svg") > -1);
        }
    }
}