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//-----------------------------------------------------------------------------
// 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;
}
}
}
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