Question

I have a thread, I need to call a void like this :

makegraph(toplot, ite, mm_0)

However if I want to synchronize I should use SynchronizationContext and do :

SynchronizationContext mContext = null;
mContext.Post(new SendOrPostCallback(makegraph(toplot, ite, mm_0)),null);

But I have the followinf error : Method name expected .
I know that I should use delegates but I am not familiar with the syntax.

Can you help me on that please ?

Answer 1

First off, your mContext variable is never set to an instance of SynchronizationContext, it’s initialized to null.

The function SynchronizationContext.Post() expects two arguments, one of type SendOrPostCallback, and one of type object.

• If you look at the documentation for SendOrPostCallback, it is a delegate that returns void and expects a single object parameter as input.
• The object state parameter of the Post function is the parameter that will get passed into the delegate specified in the first paramter.

That means, you will need to make a new makegraph function that matches the signature of the SendOrPostCallback delegate, and then pass in all of the paramters in a single object, like so:

public class MakeGraphState()
{
    // These don't have to be objects, but I don't know
    // what types your toplot, ite, and mm_0 paramters are
    public object toplot { get; set; }
    public object ite { get; set; }
    public object mm_0 { get; set; }
}

public static void makegraph(object state)
{
    // Convert state to a MakeGraphState so we can get
    // all of the input paramters
    MakeGraphState myState = (MakeGraphState)object;
    makegraph(myState.toplot, myState.ite, myState.mm_0);
}

You could then use this code like so:

SynchronizationContext mContext = new SynchronizationContext();
// TODO: Initialize your SynchronizationContext
MakeGraphState state = new MakeGraphState(toplot, ite, mm_0);
mContext.Post(new SendOrPostCallback(makegraph), state);

In addition, you can just pass in your method name for the delegate as a shortcut:

SynchronizationContext mContext = null;
// TODO: Initialize your SynchronizationContext
MakeGraphState state = new MakeGraphState(toplot, ite, mm_0);
mContext.Post(makegraph, state);

For more info on delegates, see the MSDN article Delegates (C# Programming Guide)
.