Destination Array not long enough?

Question

I have a class with the following method:

public List bikesCopy 
{
     get 
     { 
       List bs;
       lock (_bikes) bs = new Li         


        

Answer 1

This error occurs because multiple threads are adding items in a single list. Lists are by default not a thread-safe solution. In a multi-threaded code, it is only recommended to read from a list, and not write to it.

As described here:

If you are only reading from a shared collection, then you can use the classes in the System.Collections.Generic namespace.

Better use a thread-safe solution like System.Collections.Concurrent namespace which provides implementations like ConcurrentBag, ConcurrentDictionary, ConcurrentQueue, ConcurrentStack etc.

For example:

public ConcurrentBag bikesCopy 
{
     get => new ConcurrentBag()
}