public override IGraphCloneable Clone(CloneContext cloneContext) { DxfAttributeDefinition attributeDefinition = (DxfAttributeDefinition)cloneContext.GetExistingClone((IGraphCloneable)this); if (attributeDefinition == null) { attributeDefinition = new DxfAttributeDefinition(); cloneContext.RegisterClone((IGraphCloneable)this, (IGraphCloneable)attributeDefinition); attributeDefinition.CopyFrom((DxfHandledObject)this, cloneContext); } return((IGraphCloneable)attributeDefinition); }