java的synchronized关键字的C#版本？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/541194/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
C# version of java's synchronized keyword?
提问by Soraz
Does c# have its own version of the java "synchronized" keyword?
c# 是否有自己版本的 java“同步”关键字？
I.e. in java it can be specified either to a function, an object or a block of code, like so:
即在 Java 中，它可以指定为函数、对象或代码块，如下所示：
public synchronized void doImportantStuff() {
// dangerous code goes here.
}
or
或者
public void doImportantStuff() {
// trivial stuff
synchronized(someLock) {
// dangerous code goes here.
}
}
采纳答案by Marc Gravell
First - most classes will never need to be thread-safe. Use YAGNI: only apply thread-safety when you know you actually are going to use it (and test it).
首先 - 大多数类永远不需要是线程安全的。使用YAGNI：仅当您知道您确实要使用它（并测试它）时才应用线程安全。
For the method-level stuff, there is [MethodImpl]:
对于方法级的东西，有[MethodImpl]：
[MethodImpl(MethodImplOptions.Synchronized)]
public void SomeMethod() {/* code */}
This can also be used on accessors (properties and events):
这也可以用于访问器（属性和事件）：
private int i;
public int SomeProperty
{
[MethodImpl(MethodImplOptions.Synchronized)]
get { return i; }
[MethodImpl(MethodImplOptions.Synchronized)]
set { i = value; }
}
Note that field-like events aresynchronized by default, while auto-implemented properties are not:
请注意，字段类事件默认是同步的，而自动实现的属性不是：
public int SomeProperty {get;set;} // not synchronized
public event EventHandler SomeEvent; // synchronized
Personally, I don't like the implementation of MethodImplas it locks thisor typeof(Foo)- which is against best practice. The preferred option is to use your own locks:
就个人而言，我不喜欢实现MethodImplas it locksthis或typeof(Foo)- 这违反了最佳实践。首选选项是使用您自己的锁：
private readonly object syncLock = new object();
public void SomeMethod() {
lock(syncLock) { /* code */ }
}
Note that for field-like events, the locking implementation is dependent on the compiler; in older Microsoft compilers it is a lock(this)/ lock(Type)- however, in more recent compilers it uses Interlockedupdates - so thread-safe without the nasty parts.
请注意，对于类似字段的事件，锁定实现取决于编译器；在较旧的 Microsoft 编译器中，它是lock(this)/ lock(Type)- 但是，在较新的编译器中，它使用Interlocked更新 - 因此线程安全，没有讨厌的部分。
This allows more granular usage, and allows use of Monitor.Wait/Monitor.Pulseetc to communicate between threads.
这允许更细粒度的使用，并允许使用Monitor.Wait/ Monitor.Pulseetc 在线程之间进行通信。
A related blog entry(later revisited).
回答by Konrad Rudolph
Does c# have its own version of the java "synchronized" keyword?
c# 是否有自己版本的 java“同步”关键字？
No. In C#, you explicitly lockresources that you want to work on synchronously across asynchronous threads. lockopens a block; it doesn't work on method level.
否。在 C# 中，您可以明确指定lock要跨异步线程同步处理的资源。lock打开一个块；它在方法级别不起作用。
However, the underlying mechanism is similar since lockworks by invoking Monitor.Enter(and subsequently Monitor.Exit) on the runtime. Java works the same way, according to the Sun documentation.
但是，底层机制是相似的，因为lock通过在运行时调用Monitor.Enter（以及随后的Monitor.Exit）来工作。根据Sun 文档，Java 的工作方式相同。
回答by Jan Gressmann
static object Lock = new object();
lock (Lock)
{
// do stuff
}
回答by James
You can use the lockstatement instead. I think this can only replace the second version. Also, remember that both synchronizedand lockneed to operate on an object.
您可以改用该lock语句。我认为这只能替代第二个版本。另外，请记住，synchronized和 都lock需要对一个对象进行操作。
回答by Traubenfuchs
Take note, with full paths the line: [MethodImpl(MethodImplOptions.Synchronized)]should look like
请注意，完整路径的行：[MethodImpl(MethodImplOptions.Synchronized)]应该看起来像
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.Synchronized)]
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.Synchronized)]
