#region License
/*
* Copyright 2002-2005 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#endregion
#region Imports
using System;
using System.Reflection;
using Spring.Core;
using Spring.Objects.Support;
using Spring.Util;
#endregion
namespace Spring.Objects.Events.Support{
/// <summary>
/// Utility class to aid in the manipulation of events and delegates.
/// </summary>
/// <author>Griffin Caprio</author>
public sealed class EventManipulationUtils
{
/// <summary>
/// Returns a new instance of the requested <see cref="Delegate"/>.
/// </summary>
/// <remarks>
/// <p>
/// Often used to wire subscribers to event publishers.
/// </p>
/// </remarks>
/// <param name="delegateType">
/// The <see cref="System.Type"/> of delegate to create.
/// </param>
/// <param name="targetSubscriber">
/// The target subscriber object that contains the delegate implementation.
/// </param>
/// <param name="targetSubscriberDelegateMethod">
/// <see cref="MethodInfo"/> referencing the delegate method on the subscriber.
/// </param>
/// <returns>
/// A delegate handler that can be added to an events list of handlers, or called directly.
/// </returns>
public static Delegate GetHandlerDelegate(
Type delegateType, object targetSubscriber, MethodInfo targetSubscriberDelegateMethod)
{
return Delegate.CreateDelegate(
delegateType, targetSubscriber, targetSubscriberDelegateMethod.Name);
}
/// <summary>
/// Queries the input type for a <see cref="MethodInfo" /> signature matching the input
/// <see cref="MethodInfo"/> signature.
/// </summary>
/// <remarks>
/// Typically used to query a potential subscriber to see if they implement an event handler.
/// </remarks>
/// <param name="invoke"><see cref="MethodInfo"/> to match against</param>
/// <param name="subscriberType"><see cref="Type"/> to query</param>
/// <returns>
/// <see cref="MethodInfo"/> matching input <see cref="MethodInfo"/>
/// signature, or <see langword="null"/> if there is no match.
/// </returns>
public static MethodInfo GetMethodInfoMatchingSignature(
MethodInfo invoke, Type subscriberType)
{
ParameterInfo[] parameters = invoke.GetParameters();
ComposedCriteria criteria = new ComposedCriteria();
criteria.Add(new MethodReturnTypeCriteria(invoke.ReturnType));
criteria.Add(new MethodParametersCountCriteria(parameters.Length));
criteria.Add(new MethodParametersCriteria(ReflectionUtils.GetParameterTypes(parameters)));
MemberInfo[] methods = subscriberType.FindMembers(
MemberTypes.Method, ReflectionUtils.AllMembersCaseInsensitiveFlags,
new MemberFilter(new CriteriaMemberFilter().FilterMemberByCriteria),
criteria);
if (methods != null
&& methods.Length > 0)
{
return methods[0] as MethodInfo;
}
return null;
}
#region Constructor (s) / Destructor
// CLOVER:OFF
/// <summary>
/// Creates a new instance of the EventManipulationUtilities class.
/// </summary>
/// <remarks>
/// <p>
/// This is a utility class, and as such has no publicly visible constructors.
/// </p>
/// </remarks>
private EventManipulationUtils()
{
}
// CLOVER:ON
#endregion
}
}
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