How to safely use eventBus. AsynRegister

[bxjg1987]

abp 8.2

I am using the blazer server and want to notify the UI when entities change, so I need to dynamically register events.

Thread A is triggering an event, while thread B is registering or unregistering the event,

The foreach loop in thread A will prompt the error that the collection has been modified.

System.InvalidOperationException: Collection was modified; enumeration operation may not execute.
   at Abp.Events.Bus.EventBus.Trigger(Type eventType, Object eventSource, IEventData eventData)
   at Abp.Domain.Uow.UnitOfWorkBase.CompleteAsync()
   at ZLJ.App.Admin.Equipments.EquipmentInstances.BXJGEquipmentInstanceAppService.ChangeLifeCycleStatus(BatchChangeLifetimeStatusInput input) in D:\fyj\back\src\ZLJ.Application\Equipments\EquipmentInstances\BXJGEquipmentInstanceAppService.cs:line 315

There are two ways I envision to handle it:

1. Lock, not advisable, performance is too low in high concurrency scenarios.
2. When traversing, the original collection calls ToList()

[ismcagdas]

Could you provide sample code to reproduce this problem ?

[netty2019]

Could you provide sample code to reproduce this problem ?
@ismcagdas
I have encountered the same problem, attached is the console demo
EventBusConsoleDemo.zip

[netty2019]

@ismcagdas

[HenriqueHilleshein]

I think this issue might be tightly related to the issue that I opened. #6726
I think if the collection of the event handlers is changed while triggering an event, this exception will be thrown.
Maybe this issue is then a duplicate