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//----------------------------------------------------------------
// Copyright (c) Microsoft Corporation. All rights reserved.
//----------------------------------------------------------------
namespace System.Activities.Expressions
{
using System.Activities.Validation;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq.Expressions;
using System.Runtime;
static class BinaryExpressionHelper
{
public static void OnGetArguments<TLeft, TRight>(CodeActivityMetadata metadata, InArgument<TLeft> left, InArgument<TRight> right)
{
RuntimeArgument rightArgument = new RuntimeArgument("Right", typeof(TRight), ArgumentDirection.In, true);
metadata.Bind(right, rightArgument);
RuntimeArgument leftArgument = new RuntimeArgument("Left", typeof(TLeft), ArgumentDirection.In, true);
metadata.Bind(left, leftArgument);
metadata.SetArgumentsCollection(
new Collection<RuntimeArgument>
{
rightArgument,
leftArgument
});
}
public static bool TryGenerateLinqDelegate<TLeft, TRight, TResult>(ExpressionType operatorType, out Func<TLeft, TRight, TResult> function, out ValidationError validationError)
{
function = null;
validationError = null;
ParameterExpression leftParameter = Expression.Parameter(typeof(TLeft), "left");
ParameterExpression rightParameter = Expression.Parameter(typeof(TRight), "right");
try
{
BinaryExpression binaryExpression = Expression.MakeBinary(operatorType, leftParameter, rightParameter);
Expression expressionToCompile = OperatorPermissionHelper.InjectReflectionPermissionIfNecessary(binaryExpression.Method, binaryExpression);
Expression<Func<TLeft, TRight, TResult>> lambdaExpression = Expression.Lambda<Func<TLeft, TRight, TResult>>(expressionToCompile, leftParameter, rightParameter);
function = lambdaExpression.Compile();
return true;
}
catch (Exception e)
{
if (Fx.IsFatal(e))
{
throw;
}
validationError = new ValidationError(e.Message);
return false;
}
}
}
}
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