Synchronized methods in C#

Question

Part of porting a Java application to C# is to implement a synchronized message buffer in C#. By synchronized I mean that it should be safe for threads to write and read messages to and from it.

In Java this can be solved using synchronized methods and wait() and notifyAll().

Example:

public class MessageBuffer {
    // Shared resources up here

    public MessageBuffer() {
        // Initiating the shared resources
    }

    public synchronized void post(Object obj) {
        // Do stuff
        wait();
        // Do more stuff
        notifyAll();
        // Do even more stuff
    }

    public synchronized Object fetch() {
        // Do stuff
        wait();
        // Do more stuff
        notifyAll();
        // Do even more stuff and return the object
    }
}

How can I achieve something similar in C#?

Answer 1

In .NET you can use the lock-statement like in

object oLock = new object();
lock(oLock){
  //do your stuff here
}

What you are looking for are mutexes or events. You can use the ManualResetEvent-class and make a thread wait via

ManualResetEvent mre = new ManualResetEvent(false);
...
mre.WaitOne();

The other thread eventually calls

mre.Set();

to signal the other thread that it can continue.

Look here.

Answer 2

Try this:

using System.Runtime.CompilerServices;
using System.Threading;

public class MessageBuffer
{
    // Shared resources up here

    public MessageBuffer()
    {
        // Initiating the shared resources
    }

    [MethodImpl(MethodImplOptions.Synchronized)]
    public virtual void post(object obj)
    {
        // Do stuff
        Monitor.Wait(this);
        // Do more stuff
        Monitor.PulseAll(this);
        // Do even more stuff
    }

    [MethodImpl(MethodImplOptions.Synchronized)]
    public virtual object fetch()
    {
        // Do stuff
        Monitor.Wait(this);
        // Do more stuff
        Monitor.PulseAll(this);
        // Do even more stuff and return the object
    }
}