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//-----------------------------------------------------------------------------
// Copyright (c) Microsoft Corporation. All rights reserved.
//-----------------------------------------------------------------------------
namespace Microsoft.CSharp.Activities
{
using System;
using System.Activities;
using System.Activities.Expressions;
using System.Activities.XamlIntegration;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq.Expressions;
using System.Windows.Markup;
[DebuggerStepThrough]
[ContentProperty("ExpressionText")]
public class CSharpReference<TResult> : CodeActivity<Location<TResult>>, ITextExpression
{
CompiledExpressionInvoker invoker;
public CSharpReference()
{
this.UseOldFastPath = true;
}
public CSharpReference(string expressionText) :
this()
{
this.ExpressionText = expressionText;
}
public string ExpressionText
{
get;
set;
}
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public string Language
{
get
{
return "C#";
}
}
public bool RequiresCompilation
{
get
{
return true;
}
}
protected override void CacheMetadata(CodeActivityMetadata metadata)
{
this.invoker = new CompiledExpressionInvoker(this, true, metadata);
}
protected override Location<TResult> Execute(CodeActivityContext context)
{
Location<TResult> value = (Location<TResult>)this.invoker.InvokeExpression(context);
return value;
}
public Expression GetExpressionTree()
{
if (this.IsMetadataCached)
{
return this.invoker.GetExpressionTree();
}
else
{
throw FxTrace.Exception.AsError(new InvalidOperationException(SR.ActivityIsUncached));
}
}
}
}
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