public void UpdateThumbnailEx()
{
//ExStart
//ExFor:Document.UpdateThumbnail()
//ExFor:Document.UpdateThumbnail(ThumbnailGeneratingOptions)
//ExSummary:Shows how to update a document's thumbnail.
Aspose.Words.Document doc = new Aspose.Words.Document();
// Update document's thumbnail the default way.
doc.UpdateThumbnail();
// Review/change thumbnail options and then update document's thumbnail.
ThumbnailGeneratingOptions tgo = new ThumbnailGeneratingOptions();
Console.WriteLine("Thumbnail size: {0}", tgo.ThumbnailSize);
tgo.GenerateFromFirstPage = true;
doc.UpdateThumbnail(tgo);
//ExEnd
}