private void ValidateCustomXmlElement(CustomXmlElement e)
 {
     e.Uri = uri;
     e.Element = element;
     Assert.NotNull(e.Uri);
     Assert.Equal(typeof(StringValue), e.Uri.GetType());
     Assert.Equal(uri, e.Uri.Value);
     Assert.NotNull(e.Element);
     Assert.Equal(typeof(StringValue), e.Element.GetType());
     Assert.Equal(element, e.Element.Value);
 }
 private static void TransferChildElements(CustomXmlElement from, OpenXmlCompositeElement to)
 {
     OpenXmlElement[] elements = from.ChildElements.ToArray();
     foreach (var e in elements)
     {
         e.Remove();
     }
     to.Append(elements);
 }