# RhinoReplaceObjectEventArgs class

Namespace: [Rhino.DocObjects](https://developer.rhino3d.com/api/rhinocommon/namespace/rhino.docobjects.md) · Assembly: [RhinoCommon](https://developer.rhino3d.com/api/rhinocommon/assembly/rhinocommon.md) · Since v5.0

```cs
public class RhinoReplaceObjectEventArgs : EventArgs
```

[RhinoDoc.ReplaceRhinoObject](https://developer.rhino3d.com/api/rhinocommon/type/rhino.rhinodoc/replacerhinoobject.md) event arguments.

## Properties

- [Document](https://developer.rhino3d.com/api/rhinocommon/type/rhino.docobjects.rhinoreplaceobjecteventargs/document.md): The document where the event occurred.
- [DocumentSerialNumber](https://developer.rhino3d.com/api/rhinocommon/type/rhino.docobjects.rhinoreplaceobjecteventargs/documentserialnumber.md): The document runtime serial number.
- [NewRhinoObject](https://developer.rhino3d.com/api/rhinocommon/type/rhino.docobjects.rhinoreplaceobjecteventargs/newrhinoobject.md): The new replacement object, or the object about to be added. At the time [RhinoDoc.ReplaceRhinoObject](https://developer.rhino3d.com/api/rhinocommon/type/rhino.rhinodoc/replacerhinoobject.md) is called, this object has not been added to the document. Thus, this object's id will be [Guid.Empty](https://learn.microsoft.com/dotnet/api/system.guid.empty).
- [ObjectId](https://developer.rhino3d.com/api/rhinocommon/type/rhino.docobjects.rhinoreplaceobjecteventargs/objectid.md): The id of the existing object, or the object about to be deleted. At the time [RhinoDoc.ReplaceRhinoObject](https://developer.rhino3d.com/api/rhinocommon/type/rhino.rhinodoc/replacerhinoobject.md) is called, this object has not been deleted.
- [OldRhinoObject](https://developer.rhino3d.com/api/rhinocommon/type/rhino.docobjects.rhinoreplaceobjecteventargs/oldrhinoobject.md): The existing object, or the object about to be deleted. At the time [RhinoDoc.ReplaceRhinoObject](https://developer.rhino3d.com/api/rhinocommon/type/rhino.rhinodoc/replacerhinoobject.md) is called, this object has not been deleted.