显示器VS锁 [英] Monitor vs lock

问题描述

当它是适当的，以使用显示器类或C＃中的锁定关键字线程安全？

When is it appropriate to use either the Monitor class or the lock keyword for thread safety in C#?

编辑： 它似乎离答案至今的锁定短手的一系列调用显示器类。到底是什么锁调用短手？或者更明确地说，

It seems from the answers so far that lock is short hand for a series of calls to the Monitor class. What exactly is the lock call short-hand for? Or more explicitly,

class LockVsMonitor
{
    private readonly object LockObject = new object();
    public void DoThreadSafeSomethingWithLock(Action action)
    {
        lock (LockObject)
        {
            action.Invoke();
        }
    }
    public void DoThreadSafeSomethingWithMonitor(Action action)
    {
        // What goes here ?
    }
}

更新

感谢大家的帮助：我已经发布了一个又一个的问题作为后续行动，一些你提供的所有信息。既然你似乎深谙这方面，我已经发布的链接：<一href="http://stackoverflow.com/questions/4979331/what-is-wrong-with-this-solution-to-locking-and-managing-locked-exceptions">What不对这个解决方案，锁定和管理锁定例外？

Thank you all for your help : I have posted a another question as a follow up to some of the information you all provided. Since you seem to be well versed in this area, I have posted the link: What is wrong with this solution to locking and managing locked exceptions?

推荐答案

这个在他的博客埃里克利珀会谈： <一href="http://blogs.msdn.com/b/ericlippert/archive/2009/03/06/locks-and-exceptions-do-not-mix.aspx">Locks和异常不混合

Eric Lippert talks about this in his blog: Locks and exceptions do not mix

相当于code C＃4.0和更早的版本是不同的。

The equivalent code differs between C# 4.0 and earlier versions.

在C＃4.0，它是：

bool lockWasTaken = false;
var temp = obj;
try
{
    Monitor.Enter(temp, ref lockWasTaken);
    { body }
}
finally
{
    if (lockWasTaken) Monitor.Exit(temp);
}

它依赖于 Monitor.Enter 原子设置标志，采取了锁的时候。

It relies on Monitor.Enter atomically setting the flag when the lock is taken.

和以前它是：

var temp = obj;
Monitor.Enter(temp);
try
{
   body
}
finally
{
    Monitor.Exit(temp);
}

这依赖于在 Monitor.Enter 被抛出也不例外，在尝试。我认为，在调试code这种情况下被侵犯，因为编译器插入它们之间的NOP，从而取得这些可能的线程流产。

This relies on no exception being thrown between Monitor.Enter and the try. I think in debug code this condition was violated because the compiler inserted a NOP between them and thus made thread abortion between those possible.

这篇关于显示器VS锁的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！