Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Activities/System/Activities/Statements/FlowSwitch.cs

@@ -0,0 +1,136 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) Microsoft Corporation.  All rights reserved.
+//-----------------------------------------------------------------------------
+
+namespace System.Activities.Statements
+{
+    using System.Activities;
+    using System.Collections.Generic;
+    using System.ComponentModel;
+    using System.Runtime;
+    using System.Runtime.Collections;
+    using System.Windows.Markup;
+
+    [ContentProperty("Cases")]
+    public sealed class FlowSwitch<T> : FlowNode, IFlowSwitch
+    {
+        const string DefaultDisplayName = "Switch";
+        internal IDictionary<T, FlowNode> cases;
+        CompletionCallback<T> onSwitchCompleted;
+        string displayName;
+
+        public FlowSwitch()
+        {
+            this.cases = new NullableKeyDictionary<T, FlowNode>();
+            this.displayName = FlowSwitch<T>.DefaultDisplayName;
+        }
+
+        [DefaultValue(null)]
+        public Activity<T> Expression
+        {
+            get;
+            set;
+        }
+
+        [DefaultValue(null)]
+        public FlowNode Default
+        {
+            get;
+            set;
+        }
+
+        [Fx.Tag.KnownXamlExternal]
+        public IDictionary<T, FlowNode> Cases
+        {
+            get
+            {
+                return this.cases;
+            }
+        }
+
+        [DefaultValue(FlowSwitch<T>.DefaultDisplayName)]
+        public string DisplayName
+        {
+            get
+            {
+                return this.displayName;
+            }
+            set
+            {
+                this.displayName = value;
+            }
+        }
+
+        internal override void OnOpen(Flowchart owner, NativeActivityMetadata metadata)
+        {
+            if (this.Expression == null)
+            {
+                metadata.AddValidationError(SR.FlowSwitchRequiresExpression(owner.DisplayName));
+            }
+        }
+
+        internal override void GetConnectedNodes(IList<FlowNode> connections)
+        {
+            foreach (KeyValuePair<T, FlowNode> item in this.Cases)
+            {
+                connections.Add(item.Value);
+            }
+            if (this.Default != null)
+            {
+                connections.Add(this.Default);
+            }
+        }
+
+        internal override Activity ChildActivity
+        {
+            get { return Expression; }
+        }
+
+        bool IFlowSwitch.Execute(NativeActivityContext context, Flowchart parent)
+        {
+            context.ScheduleActivity(Expression, this.GetSwitchCompletedCallback(parent));
+            return false;
+        }
+
+        FlowNode IFlowSwitch.GetNextNode(object value)
+        {
+            FlowNode result;
+            T newValue = (T)value;
+            if (Cases.TryGetValue(newValue, out result))
+            {
+                if (TD.FlowchartSwitchCaseIsEnabled())
+                {
+                    TD.FlowchartSwitchCase(this.Owner.DisplayName, newValue.ToString());
+                }
+                return result;
+            }
+            else
+            {
+                if (this.Default != null)
+                {
+                    if (TD.FlowchartSwitchDefaultIsEnabled())
+                    {
+                        TD.FlowchartSwitchDefault(this.Owner.DisplayName);
+                    }
+                }
+                else
+                {
+                    if (TD.FlowchartSwitchCaseNotFoundIsEnabled())
+                    {
+                        TD.FlowchartSwitchCaseNotFound(this.Owner.DisplayName);
+                    }
+                }
+                return this.Default;
+            }
+        }
+
+        CompletionCallback<T> GetSwitchCompletedCallback(Flowchart parent)
+        {
+            if (onSwitchCompleted == null)
+            {
+                onSwitchCompleted = new CompletionCallback<T>(parent.OnSwitchCompleted<T>);
+            }
+            return onSwitchCompleted;
+        }
+    }
+}