Delay.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / cdf / src / NetFx40 / System.Activities / System / Activities / Statements / Delay.cs / 1305376 / Delay.cs
                        

                        
                            //------------------------------------------------------------------------------ 
// Copyright (c) Microsoft Corporation.  All rights reserved.
//-----------------------------------------------------------------------------

namespace System.Activities.Statements 
{
    using System; 
    using System.Activities; 
    using System.Collections.ObjectModel;
    using System.ComponentModel; 
    using System.Runtime;
    using System.Windows.Markup;

    [ContentProperty("Duration")] 
    public sealed class Delay : NativeActivity
    { 
        static Func getDefaultTimerExtension = new Func(GetDefaultTimerExtension); 
        Variable timerBookmark;
 
        public Delay()
            : base()
        {
            this.timerBookmark = new Variable(); 
        }
 
        [RequiredArgument] 
        [DefaultValue(null)]
        public InArgument Duration 
        {
            get;
            set;
        } 

        protected override bool CanInduceIdle 
        { 
            get
            { 
                return true;
            }
        }
 
        protected override void CacheMetadata(NativeActivityMetadata metadata)
        { 
            RuntimeArgument durationArgument = new RuntimeArgument("Duration", typeof(TimeSpan), ArgumentDirection.In, true); 
            metadata.Bind(this.Duration, durationArgument);
            metadata.SetArgumentsCollection(new Collection { durationArgument }); 
            metadata.AddImplementationVariable(this.timerBookmark);
            metadata.AddDefaultExtensionProvider(getDefaultTimerExtension);
        }
 
        static TimerExtension GetDefaultTimerExtension()
        { 
            return new DurableTimerExtension(); 
        }
 
        protected override void Execute(NativeActivityContext context)
        {
            TimeSpan duration = this.Duration.Get(context);
            if (duration < TimeSpan.Zero) 
            {
                throw FxTrace.Exception.ArgumentOutOfRange("Duration", duration, SR.DurationIsNegative(this.DisplayName)); 
            } 

            if (duration == TimeSpan.Zero) 
            {
                return;
            }
 
            TimerExtension timerExtension = GetTimerExtension(context);
            Bookmark bookmark = context.CreateBookmark(); 
            timerExtension.RegisterTimer(duration, bookmark); 
            this.timerBookmark.Set(context, bookmark);
        } 

        protected override void Cancel(NativeActivityContext context)
        {
            Bookmark timerBookmark = this.timerBookmark.Get(context); 
            TimerExtension timerExtension = GetTimerExtension(context);
            timerExtension.CancelTimer(timerBookmark); 
            context.RemoveBookmark(timerBookmark); 
            context.MarkCanceled();
        } 

        protected override void Abort(NativeActivityAbortContext context)
        {
            Bookmark timerBookmark = this.timerBookmark.Get(context); 
            // The bookmark could be null in abort when user passed in a negative delay as a duration
            if (timerBookmark != null) 
            { 
                TimerExtension timerExtension = GetTimerExtension(context);
                timerExtension.CancelTimer(timerBookmark); 
            }
            base.Abort(context);
        }
 
        TimerExtension GetTimerExtension(ActivityContext context)
        { 
            TimerExtension timerExtension = context.GetExtension(); 
            Fx.Assert(timerExtension != null, "TimerExtension must exist.");
            return timerExtension; 
        }
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.

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