FuncCompletionCallbackWrapper.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 / Runtime / FuncCompletionCallbackWrapper.cs / 1305376 / FuncCompletionCallbackWrapper.cs
                        

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

namespace System.Activities.Runtime 
{
    using System; 
    using System.Collections.Generic; 
    using System.Text;
    using System.Runtime.Serialization; 
    using System.Runtime;
    using System.Security;

    [DataContract] 
    class FuncCompletionCallbackWrapper : CompletionCallbackWrapper
    { 
        static Type callbackType = typeof(CompletionCallback); 
        static Type[] callbackParameterTypes = new Type[] { typeof(NativeActivityContext), typeof(ActivityInstance),typeof(T) };
 
        [DataMember(EmitDefaultValue = false)]
        T resultValue;

        public FuncCompletionCallbackWrapper(CompletionCallback callback, ActivityInstance owningInstance) 
            : base(callback, owningInstance)
        { 
            this.NeedsToGatherOutputs = true; 
        }
 
        int GetResultId(ActivityWithResult activity)
        {
            if (activity.Result != null)
            { 
                return activity.Result.Id;
            } 
            else 
            {
                for (int i = 0; i < activity.RuntimeArguments.Count; i++) 
                {
                    RuntimeArgument argument = activity.RuntimeArguments[i];

                    if (argument.IsResult) 
                    {
                        return argument.Id; 
                    } 
                }
            } 

            return -1;
        }
 
        protected override void GatherOutputs(ActivityInstance completedInstance)
        { 
            int resultId = -1; 

            if (completedInstance.Activity.HandlerOf != null) 
            {
                DelegateOutArgument resultArgument = completedInstance.Activity.HandlerOf.GetResultArgument();
                if (resultArgument != null)
                { 
                    resultId = resultArgument.Id;
                } 
                else 
                {
                    ActivityWithResult activity = completedInstance.Activity as ActivityWithResult; 
                    // for auto-generated results, we should bind the value from the Handler if available
                    if (activity != null && TypeHelper.AreTypesCompatible(activity.ResultType, typeof(T)))
                    {
                        resultId = GetResultId(activity); 
                    }
                } 
            } 
            else
            { 
                Fx.Assert(completedInstance.Activity is ActivityWithResult, "should only be using FuncCompletionCallbackWrapper with ActivityFunc and ActivityWithResult");
                resultId = GetResultId((ActivityWithResult)completedInstance.Activity);
            }
 
            if (resultId >= 0)
            { 
                Location location = completedInstance.Environment.GetSpecificLocation(resultId); 
                Location typedLocation = location as Location;
 
                if (typedLocation != null)
                {
                    this.resultValue = typedLocation.Value;
                } 
                else if (location != null)
                { 
                    this.resultValue = TypeHelper.Convert(location.Value); 
                }
            } 
        }

        protected internal override void Invoke(NativeActivityContext context, ActivityInstance completedInstance)
        { 
            // Call the EnsureCallback overload that also looks for SomeMethod where T is the result type
            // and the signature matches. 
            EnsureCallback(callbackType, callbackParameterTypes, callbackParameterTypes[2]); 
            CompletionCallback completionCallback = (CompletionCallback)this.Callback;
            completionCallback(context, completedInstance, this.resultValue); 
        }

        protected override void OnSerializingGenericCallback()
        { 
            ValidateCallbackResolution(callbackType, callbackParameterTypes, callbackParameterTypes[2]);
        } 
    } 
}

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

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