Checks for reentrant attempts to change this collection.
Assemblies: System.ObjectModel (in System.ObjectModel.dll)
System (in System.dll)
If there was a call to BlockReentrancy of which the IDisposable return value has not yet been disposed of. Typically, this means when there are additional attempts to change this collection during a CollectionChanged event. However, it depends on when derived classes choose to call BlockReentrancy.