c# - 字典查找是否需要锁定？

Question

lock(dictionaryX)
{
   dictionaryX.TryGetValue(key, out value);
}

在查找字典时是否需要锁定？

该程序是多线程的，同时向字典添加键/值。字典被锁定。

Answer 1

如前所述here :

Using TryGetValue() without locking is not safe. The dictionary is temporarily in a state that makes it unsuitable for reading while another thread is writing the dictionary. A dictionary will reorganize itself from time to time as the number of entries it contains grows. When you read at the exact time this re-organization takes place, you'll run the risk of finding the wrong value for the key when the buckets got updated but not yet the value entries.

更新: 查看 this page 的“线程安全”部分也是。