asp.net并发访问静态变量

Question

Static vars can be read simultaneously by users?

     public static ConcurrentDictionary<string, object> aStaticDictionary= new ConcurrentDictionary<string, object>();

When an user read the dictionary

    aStaticDictionary["key"]

Concurrent requests are queued?

Answer 1

Yes, with some caveats. Static vars can be read by multiple threads but aren't shared between processes. That's important if you've configured your IIS app pool to have more than one worker process.

You can't predict the order that different threads will access the dictionary. The ConcurrentDictionary only guarantees that reads which are made simultaneously with writes to the dictionary won't cause problems whereas they may have done if use used the standard Dictonary class.