EventHandlingScope.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 / WF / Activities / EventHandlingScope.cs / 1305376 / EventHandlingScope.cs
                        

                        
                            namespace System.Workflow.Activities 
{
    #region Imports

    using System; 
    using System.Text;
    using System.Reflection; 
    using System.Collections; 
    using System.CodeDom;
    using System.ComponentModel; 
    using System.ComponentModel.Design;
    using System.ComponentModel.Design.Serialization;
    using System.Drawing;
    using System.Drawing.Drawing2D; 
    using System.Workflow.ComponentModel;
    using System.Workflow.ComponentModel.Design; 
    using System.Workflow.ComponentModel.Compiler; 
    using System.Workflow.Activities.Common;
 
    #endregion

    [SRDescription(SR.EventHandlingScopeActivityDescription)]
    [ToolboxItem(typeof(ActivityToolboxItem))] 
    [ToolboxBitmap(typeof(EventHandlingScopeActivity), "Resources.Sequence.png")]
    [ActivityValidator(typeof(EventHandlingScopeValidator))] 
    [Designer(typeof(EventHandlingScopeDesigner), typeof(IDesigner))] 
    public sealed class EventHandlingScopeActivity : CompositeActivity, IActivityEventListener
    { 
        public EventHandlingScopeActivity()
        {
        }
        public EventHandlingScopeActivity(string name) 
            : base(name)
        { 
        } 

        protected override ActivityExecutionStatus Execute(ActivityExecutionContext executionContext) 
        {
            if (executionContext == null)
                throw new ArgumentNullException("executionContext");
 
            Activity bodyActivity = this.BodyActivity;
 
            if (bodyActivity == null) 
                return ActivityExecutionStatus.Closed;
 
            // run EventHandlers
            EventHandlersActivity eventHandlers = this.EventHandlersActivity;
            if (eventHandlers != null)
            { 
                eventHandlers.RegisterForStatusChange(Activity.ClosedEvent, this);
                executionContext.ExecuteActivity(eventHandlers); 
            } 

            // run body 
            bodyActivity.RegisterForStatusChange(Activity.ClosedEvent, this);
            executionContext.ExecuteActivity(bodyActivity);

 
            // return the status
            return this.ExecutionStatus; 
        } 
        protected override ActivityExecutionStatus Cancel(ActivityExecutionContext executionContext)
        { 
            if (executionContext == null)
                throw new ArgumentNullException("executionContext");

            Activity bodyActivity = this.BodyActivity; 
            EventHandlersActivity eventHandlers = this.EventHandlersActivity;
 
            if(bodyActivity == null && eventHandlers == null) 
                return ActivityExecutionStatus.Closed;
 
            bool cancelScheduled = false;

            // check the status of body
            if (bodyActivity != null && bodyActivity.ExecutionStatus == ActivityExecutionStatus.Executing) 
            {
                executionContext.CancelActivity(bodyActivity); 
                cancelScheduled = true; 
            }
            //Check the status of EventHandlers 
            if (eventHandlers != null && eventHandlers.ExecutionStatus == ActivityExecutionStatus.Executing)
            {
                executionContext.CancelActivity(eventHandlers);
                cancelScheduled = true; 
            }
 
            if (cancelScheduled || 
                        (bodyActivity != null && (bodyActivity.ExecutionStatus == ActivityExecutionStatus.Faulting ||
                        bodyActivity.ExecutionStatus == ActivityExecutionStatus.Canceling)) || 
                        (eventHandlers != null && (eventHandlers.ExecutionStatus == ActivityExecutionStatus.Faulting ||
                        eventHandlers.ExecutionStatus == ActivityExecutionStatus.Canceling))
                )
            { 
                return this.ExecutionStatus;
            } 
            return ActivityExecutionStatus.Closed; 
        }
 
        #region IActivityEventListener Members

        void IActivityEventListener.OnEvent(object sender, ActivityExecutionStatusChangedEventArgs e)
        { 
            ActivityExecutionContext context = sender as ActivityExecutionContext;
            if (context == null) 
                throw new ArgumentException(); 

            e.Activity.UnregisterForStatusChange(Activity.ClosedEvent, this); 
            if (e.Activity is EventHandlersActivity)
            {
                if (this.BodyActivity.ExecutionStatus == ActivityExecutionStatus.Closed)
                { 
                    context.CloseActivity();
                } 
                //else Eventhandlers faulted, let exception propagate up. 
            }
            else 
            {
                EventHandlersActivity eventHandlers = this.EventHandlersActivity;
                if (eventHandlers == null || eventHandlers.ExecutionStatus == ActivityExecutionStatus.Closed)
                { 
                    context.CloseActivity();
                } 
                else 
                {
                    eventHandlers.UnsubscribeAndClose(); 
                }
            }
        }
        #endregion 

        internal EventHandlersActivity EventHandlersActivity 
        { 
            get
            { 
                EventHandlersActivity eventHandlers = null;
                foreach (Activity child in this.EnabledActivities)
                {
                    if (child is EventHandlersActivity) 
                        eventHandlers = child as EventHandlersActivity;
                } 
                return eventHandlers; 
            }
        } 
        internal Activity BodyActivity
        {
            get
            { 
                Activity body = null;
                foreach (Activity child in this.EnabledActivities) 
                { 
                    if (!(child is EventHandlersActivity))
                        body = child; 
                }
                return body;
            }
        } 
        #region Dynamic Update Methods
 
        [NonSerialized] 
        private bool eventHandlersRemovedInDynamicUpdate = false;
        [NonSerialized] 
        private bool bodyActivityRemovedInDynamicUpdate = false;

        protected override void OnActivityChangeRemove(ActivityExecutionContext executionContext, Activity removedActivity)
        { 
            base.OnActivityChangeRemove(executionContext, removedActivity);
 
            if (removedActivity is EventHandlersActivity) 
                eventHandlersRemovedInDynamicUpdate = true;
            else 
                bodyActivityRemovedInDynamicUpdate = true;
        }

        protected override void OnWorkflowChangesCompleted(ActivityExecutionContext executionContext) 
        {
            base.OnWorkflowChangesCompleted(executionContext); 
 
            switch (this.ExecutionStatus)
            { 
                case ActivityExecutionStatus.Executing:
                    if (bodyActivityRemovedInDynamicUpdate)
                    {
                        if (EventHandlersActivity == null || EventHandlersActivity.ExecutionStatus == ActivityExecutionStatus.Closed) 
                           executionContext.CloseActivity();
                        else if(EventHandlersActivity.ExecutionStatus == ActivityExecutionStatus.Executing) 
                           EventHandlersActivity.UnsubscribeAndClose(); 
                    }
                    if (eventHandlersRemovedInDynamicUpdate) 
                    {
                        if (BodyActivity == null || BodyActivity.ExecutionStatus == ActivityExecutionStatus.Closed)
                            executionContext.CloseActivity();
                    } 
                    break;
                default: 
                    break; 
            }
            eventHandlersRemovedInDynamicUpdate = false; 
            bodyActivityRemovedInDynamicUpdate = false;
        }
        #endregion
    } 

    #region Class EventHandlingScopeValidator 
    internal sealed class EventHandlingScopeValidator : CompositeActivityValidator 
    {
        public override ValidationErrorCollection Validate(ValidationManager manager, object obj) 
        {
            ValidationErrorCollection validationErrors = base.Validate(manager, obj);

            EventHandlingScopeActivity compositeActivity = obj as EventHandlingScopeActivity; 
            if (compositeActivity == null)
                throw new ArgumentException(SR.GetString(SR.Error_UnexpectedArgumentType, typeof(EventHandlingScopeActivity).FullName), "obj"); 
 
            //we only allow one activity to be inserted
            int childCount = 0; 
            int eventHandlersCount = 0;
            foreach (Activity child in compositeActivity.EnabledActivities)
            {
                if (child is EventHandlersActivity) 
                    eventHandlersCount++;
                else 
                    childCount++; 
            }
 
            // check if more than two activities inside the collection
            if (childCount > 1)
                validationErrors.Add(new ValidationError(SR.GetString(SR.Error_MoreThanTwoActivitiesInEventHandlingScope, compositeActivity.QualifiedName), ErrorNumbers.Error_MoreThanTwoActivitiesInEventHandlingScope));
 
            // check if more than one EventHandlers
            if (eventHandlersCount > 1) 
                validationErrors.Add(new ValidationError(SR.GetString(SR.Error_MoreThanOneEventHandlersDecl, compositeActivity.GetType().Name), ErrorNumbers.Error_ScopeMoreThanOneEventHandlersDecl)); 

            return validationErrors; 
        }

        public override ValidationError ValidateActivityChange(Activity activity, ActivityChangeAction action)
        { 
            if (activity == null)
                throw new ArgumentNullException("activity"); 
            if (action == null) 
                throw new ArgumentNullException("action");
 
            if (activity.ExecutionStatus != ActivityExecutionStatus.Initialized &&
                activity.ExecutionStatus != ActivityExecutionStatus.Executing &&
                activity.ExecutionStatus != ActivityExecutionStatus.Closed)
            { 
                return new ValidationError(SR.GetString(SR.Error_DynamicActivity2, activity.QualifiedName, Enum.GetName(typeof(ActivityExecutionStatus), activity.ExecutionStatus), activity.GetType().FullName), ErrorNumbers.Error_DynamicActivity2);
            } 
            if (activity.ExecutionStatus == ActivityExecutionStatus.Executing && action is AddedActivityAction) 
            {
                return new ValidationError(SR.GetString(SR.Error_DynamicActivity3, activity.QualifiedName, Enum.GetName(typeof(ActivityExecutionStatus), activity.ExecutionStatus), activity.GetType().FullName), ErrorNumbers.Error_DynamicActivity2); 
            }
            return null;
        }
    } 
    #endregion
 
    #region Class EventHandlingScopeDesigner 

    [ActivityDesignerTheme(typeof(EventHandlingScopeActivityDesignerTheme))] 
    internal sealed class EventHandlingScopeDesigner : SequentialActivityDesigner
    {
        #region Properties and Methods
        public override bool CanExpandCollapse 
        {
            get 
            { 
                return false;
            } 
        }
        #endregion

        public override bool CanInsertActivities(HitTestInfo insertLocation, System.Collections.ObjectModel.ReadOnlyCollection activitiesToInsert) 
        {
            //we only allow one activity to be inserted 
            int childCount = 0; 
            foreach (Activity child in ((EventHandlingScopeActivity)this.Activity).Activities)
            { 
                if (!Helpers.IsFrameworkActivity(child) &&
                    !(child is EventHandlersActivity))
                    childCount++;
            } 
            if (childCount > 0)
                return false; 
 
            return base.CanInsertActivities(insertLocation, activitiesToInsert);
        } 
    }
    #endregion

    #region EventHandlingScopeActivityDesignerTheme 
    internal sealed class EventHandlingScopeActivityDesignerTheme : CompositeDesignerTheme
    { 
        public EventHandlingScopeActivityDesignerTheme(WorkflowTheme theme) 
            : base(theme)
        { 
            this.ShowDropShadow = false;
            this.ConnectorStartCap = LineAnchor.None;
            this.ConnectorEndCap = LineAnchor.ArrowAnchor;
            this.ForeColor = Color.FromArgb(0xFF, 0x00, 0x00, 0x00); 
            this.BorderColor = Color.FromArgb(0xFF, 0xE0, 0xE0, 0xE0);
            this.BorderStyle = DashStyle.Dash; 
            this.BackColorStart = Color.FromArgb(0x00, 0x00, 0x00, 0x00); 
            this.BackColorEnd = Color.FromArgb(0x00, 0x00, 0x00, 0x00);
        } 
    }
    #endregion
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK