If you place a linkbutton with a CommandName "Edit" or "Delete" the following exception is thrown:

Item type isn't valid for Add items.

The error is thrown because all items are marked as _isAddItem = true (note that in the ReorderListItem constructor there's a _isAddItem = false commented).

If add a checkbox in reorderlist, first check(or uncheck) it, and then drag this line. the checkbox will lost the state.

Add the label or Textbox can work.

This is still the case with the 1.0 Ajax Release of the Reorderlist control.  The hack around it is to enable postback on the checkbox and have code that writes the value to the database.  I put an update panel on it but it's still an ugly way of doing it.

 So this issue is still not resolved as two-way binding with a checkbox in the itemtemplate is not possible.

 The other hack is to put checkboxes in the edit template, but again, you get really ugly because you have to put EDIT command buttons on each row to get to the edit template.

Jeremy92:

This is still the case with the 1.0 Ajax Release of the Reorderlist control.  The hack around it is to enable postback on the checkbox and have code that writes the value to the database.  I put an update panel on it but it's still an ugly way of doing it.

 So this issue is still not resolved as two-way binding with a checkbox in the itemtemplate is not possible.

 The other hack is to put checkboxes in the edit template, but again, you get really ugly because you have to put EDIT command buttons on each row to get to the edit template.

Well you don't have to add much code if you two-way bind the checkbox control with your business object and associate the reorderlist with an objectdatasource.  But still you have an ugly postback.

 All of this could be avoided if the Reorderlist would correctly bind to a in-memory object like a IList or a DataTable.  As of Ajax 1.0, there's some really wierd state problems that occur if you don't
let the ReorderList write its updates to a database similar to how the demonstration does it.  

As long as the ReorderList writes an Update to a db EVERY time you drag-drop a row, it works great.

I'm not sure, but I think the ReorderList has some unexpected behavior with the ViewState and postbacks.

 Do you know if this bug has been fixed or is there a workaround?

 If add a checkbox in reorderlist, first check(or uncheck) it, and then drag this line. the checkbox will lost the state.