SynchronizationContextTaskScheduler.cs

Go to the documentation of this file.

using System.Collections.Generic;
 
namespace System.Threading.Tasks;
 
internal sealed class SynchronizationContextTaskScheduler : TaskScheduler
{
    private readonly SynchronizationContext m_synchronizationContext;
 
    private static readonly SendOrPostCallback s_postCallback = delegate(object s)
    {
        ((Task)s).ExecuteEntry();
    };
 
    public override int MaximumConcurrencyLevel => 1;
 
    internal SynchronizationContextTaskScheduler()
    {
        m_synchronizationContext = SynchronizationContext.Current ?? throw new InvalidOperationException(SR.TaskScheduler_FromCurrentSynchronizationContext_NoCurrent);
    }
 
    protected internal override void QueueTask(Task task)
    {
        m_synchronizationContext.Post(s_postCallback, task);
    }
 
    protected override bool TryExecuteTaskInline(Task task, bool taskWasPreviouslyQueued)
    {
        if (SynchronizationContext.Current == m_synchronizationContext)
        {
            return TryExecuteTask(task);
        }
        return false;
    }
 
    protected override IEnumerable<Task> GetScheduledTasks()
    {
        return null;
    }
}