c# - 列出线程安全？

Question

由于代码的原子操作外观，是否可以将以下内容视为线程安全的。我主要担心的是，如果列表需要调整大小，它在调整大小时会变成非线程安全的。

List<int> list = new List<int>(10);

public List<int> GetList()
{
  var temp = list;
  list = new List<int>(10);
  return temp;
}

TimerElapsed(int number)
{
  list.Add(number);
}

Answer 1

没有。 List<T>明确是 documented 不是是线程安全的:

It is safe to perform multiple read operations on a List, but issues can occur if the collection is modified while it’s being read. To ensure thread safety, lock the collection during a read or write operation. To enable a collection to be accessed by multiple threads for reading and writing, you must implement your own synchronization. For collections with built-in synchronization, see the classes in the System.Collections.Concurrent namespace. For an inherently thread–safe alternative, see the ImmutableList class.