Issue with IDesignerSerializationService after paste fails

[Ian Hannah]

We have implemented our own IDE which is based on an example from Microsoft.

We have implemented the IDesignerSerializationService interface in our
application.

The following steps cause a problem:

a) Start the application and drag a group box control onto the form.
b) Add two labels to the form
c) Cut the group box to the clipboard
d) Add a tabcontrol
e) Paste onto the tabcontrol

An error is displayed which states “Cannot add component of type ‘GroupBox’
to container of type ‘TabControl’. This error is displayed because at this
point a tab page has not been added or selected.

However the underlying Microsoft classes have actually added the labels to
the DesignerHost collection (the GroupBox has not been added) and so when I
build or save this out the two labels are added to the saved file (but are
not actually added to the forms control collection).

This means that the saved code file contains redundant controls which I
would like to remove.

Does anyone understand why the deserialization process is adding these
controls to the DesignerHost even though the paste cannot be completed?

Please note that the same error occurs in 2003/2005 Visual Studio IDE but
the controls from the failed paste do not seem to be added to the generated
code.

Does anyone know the magic required to “clear� the controls in the failed
paste operation?

Regards

--
Ian H