使用私有变量锁定 c#

Question

根据埃里克·冈纳森的说法

不要

• 使用锁（这个）
• 使用锁(typeof())

做 锁定私有变量，而不是用户可以看到的东西 如果您需要私钥来锁定，请使用“object key = new object()”

是什么原因？？

Answer 1

是什么原因？？

因为任何不是私有的东西都意味着可以从外部被其他人使用来锁定，或者某些不受您控制的代码会导致死锁。

最佳做法是锁定私有静态变量，如下所示：

private static object _syncRoot = new object();

然后：

lock(_syncRoot)
{
    ...
}

私有实例变量也可能是危险的，因为你的类的实例不是你作为类的实现者拥有的东西。它是拥有该实例的类的消费者。

Answer 2

在发布新问题之前，您应该真正搜索旧问题。 Lock

Darin Dimitrov 说锁定私有变量是危险的也是错误的。私有变量上的锁用于同步类的特定实例的资源。当你有

// A Client which listens to several servers
public class Client
{
private static object logSync = new object();
private readonly Dictionary<string, Server> servers = new Dictionary<string, Server>();// .... some code for initialization ...

// Disposing a server. 
public void Dispose (string serverName)
{
    //  the lock needed here is on private variable. This purpose cannot be achieved with a      
    //  lock on private static object. Well you can achieve the purpose but you will block
    //  all Client instances when you do so, which is pointless.
    //  Also notice that services is readonly, which is convenient
    //  because that is the object we took a lock on. The lock is on the same object always
    //  there is no need to unnecessarily create objects for locks.  
    lock(services)
    {
        // ... Do something cleanup here ...
        Server server;
        if (servers.TryGetValue(serverName, out server))
        {
             server.Dispose();
             servers.Remove(serverName);
        }
    }
}

// on some message that has to be logged  
public void OnMessage(string message, Server server)
{
    // This makes sure that all clients log to the same sink and 
    // the messages are processed in the order of receipt
    lock (logSync)
    {
        Log(evt);
    }
}

}