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#if NET20 || NET30 || NET35 || !NET_4_6
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
using System.Runtime.Serialization;
namespace System.Threading.Tasks
{
/// <summary>
/// Represents an exception used to communicate task cancellation.
/// </summary>
[Serializable]
internal class TaskCanceledException : LinqInternal.Core.NewOperationCanceledException
{
[NonSerialized]
private readonly Task _canceledTask; // The task which has been canceled.
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Threading.Tasks.TaskCanceledException"/> class.
/// </summary>
public TaskCanceledException() : base("A task was canceled")
{
// Empty
}
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Threading.Tasks.TaskCanceledException"/>
/// class with a specified error message.
/// </summary>
/// <param name="message">The error message that explains the reason for the exception.</param>
public TaskCanceledException(string message) : base(message)
{
// Empty
}
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Threading.Tasks.TaskCanceledException"/>
/// class with a specified error message and a reference to the inner exception that is the cause of
/// this exception.
/// </summary>
/// <param name="message">The error message that explains the reason for the exception.</param>
/// <param name="innerException">The exception that is the cause of the current exception.</param>
public TaskCanceledException(string message, Exception innerException) : base(message, innerException)
{
}
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Threading.Tasks.TaskCanceledException"/> class
/// with a reference to the <see cref="T:System.Threading.Tasks.Task"/> that has been canceled.
/// </summary>
/// <param name="task">A task that has been canceled.</param>
public TaskCanceledException(Task task) :
base("A task was canceled", task != null ? task.CancellationToken : new CancellationToken())
{
_canceledTask = task;
}
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Threading.Tasks.TaskCanceledException"/>
/// class with serialized data.
/// </summary>
/// <param name="info">The <see cref="T:System.Runtime.Serialization.SerializationInfo"/> that holds the serialized object data about the exception being thrown.</param>
/// <param name="context">The <see cref="T:System.Runtime.Serialization.StreamingContext"/> that contains contextual information about the source or destination. </param>
protected TaskCanceledException(SerializationInfo info, StreamingContext context) : base(info, context)
{
// Empty
}
/// <summary>
/// Gets the task associated with this exception.
/// </summary>
/// <remarks>
/// It is permissible for no Task to be associated with a
/// <see cref="T:System.Threading.Tasks.TaskCanceledException"/>, in which case
/// this property will return null.
/// </remarks>
public Task Task
{
get { return _canceledTask; }
}
}
}
#endif