LockRecursionException 类

定义

当进入锁定状态的递归与此锁定的递归策略不兼容时引发的异常。The exception that is thrown when recursive entry into a lock is not compatible with the recursion policy for the lock.

public ref class LockRecursionException : Exception
[System.Serializable]
public class LockRecursionException : Exception
type LockRecursionException = class
    inherit Exception
Public Class LockRecursionException
Inherits Exception
继承
LockRecursionException
属性

示例

下面的示例演示了使用 ReaderWriterLockSlim 类时 LockRecursionException 的两个原因。The following example shows two causes of LockRecursionException when using the ReaderWriterLockSlim class. 程序使用无参数构造函数创建一个 ReaderWriterLockSlim,该构造函数不允许使用递归。The program creates a ReaderWriterLockSlim by using the parameterless constructor, which disallows recursion. 然后,程序将启动进入读取模式锁定状态的线程。The program then starts a thread that enters the lock in read mode. 该线程尝试在读取模式中以递归方式进入锁定状态,并捕获产生的异常。The thread tries to enter the lock recursively in read mode, and catches the resulting exception. 最后,线程尝试进入写入模式,这可能会导致死锁。Finally, the thread tries to enter write mode, which would create a potential for deadlocks. 线程捕获产生的异常。The thread catches the resulting exception.

using System;
using System.Threading;

class Example
{
    // By default, the lock recursion policy for a new 
    // ReaderWriterLockSlim does not allow recursion.
    static ReaderWriterLockSlim rwls = new ReaderWriterLockSlim();

    static void ThreadProc()
    {
        Console.WriteLine("Acquire the reader lock.");
        rwls.EnterReadLock();

        try
        {
            Console.WriteLine("\nAttempt to acquire the reader lock recursively:");
            rwls.EnterReadLock();
        }
        catch (LockRecursionException lre)
        {
            Console.WriteLine("{0}: {1}", 
                lre.GetType().Name, lre.Message);
        }

        try
        {
            Console.WriteLine("\nAttempt to acquire the writer lock recursively:");
            rwls.EnterWriteLock();
        }
        catch (LockRecursionException lre)
        {
            Console.WriteLine("{0}: {1}", 
                lre.GetType().Name, lre.Message);
        }
    }

    static void Main()
    {
        Thread t = new Thread(ThreadProc);
        t.Start();
        t.Join();
    }
}

/* This code example produces output similar to the following:

Acquire the reader lock.

Attempt to acquire the reader lock recursively:
LockRecursionException: Recursive read lock acquisitions not allowed in this mode.

Attempt to acquire the writer lock recursively:
LockRecursionException: Write lock may not be acquired with read lock held. This pattern is prone to deadlocks. Consider using the upgrade lock.
 */
Imports System.Threading

Class Example
    ' By default, the lock recursion policy for a new 
    ' ReaderWriterLockSlim does not allow recursion.
    Private Shared rwls As New ReaderWriterLockSlim()
    
    Shared Sub ThreadProc() 
        Console.WriteLine("Acquire the reader lock.")
        rwls.EnterReadLock()
        
        Try
            Console.WriteLine(vbCrLf & _
                "Attempt to acquire the reader lock recursively:")
            rwls.EnterReadLock()
        Catch lre As LockRecursionException
            Console.WriteLine("{0}: {1}", _
                lre.GetType().Name, lre.Message)
        End Try
        
        Try
            Console.WriteLine(vbCrLf & _
                "Attempt to acquire the writer lock recursively:")
            rwls.EnterWriteLock()
        Catch lre As LockRecursionException
            Console.WriteLine("{0}: {1}", _
                lre.GetType().Name, lre.Message)
        End Try
    
    End Sub 
    
    Shared Sub Main() 

        Dim t As New Thread(AddressOf ThreadProc)
        t.Start()
        t.Join()
    
    End Sub 
End Class 

' This code example produces output similar to the following:
'
'Acquire the reader lock.
'
'Attempt to acquire the reader lock recursively:
'LockRecursionException: Recursive read lock acquisitions not allowed in this mode.
'
'Attempt to acquire the writer lock recursively:
'LockRecursionException: Write lock may not be acquired with read lock held. This pattern is prone to deadlocks. Consider using the upgrade lock.
' 

注解

引发 LockRecursionException 的原因有多种,其中包括:LockRecursionException is thrown for several reasons, including the following:

  • 如果某个线程尝试以递归方式进入 ReaderWriterLockSlim 的实例,但该实例不支持递归。If a thread tries to enter an instance of ReaderWriterLockSlim recursively, but the instance does not support recursion.

  • 当线程最初进入读取模式锁定状态时,如果线程尝试进入写入模式或可升级模式下的 ReaderWriterLockSlim 实例,则为。If a thread tries to enter a ReaderWriterLockSlim instance in write mode or upgradeable mode when the thread initially entered the lock in read mode. 这表示潜在的死锁,因此不允许这样做。This represents a potential deadlock and therefore is not allowed.

  • 如果允许一个更高的递归级别超过用于跟踪递归的内部存储计数器的最大值。If allowing one more level of recursion would exceed the maximum value for the internal storage counter used to track recursions. 此限制数值很大,因此任何情况下应用程序都不应遇到此情况。This limit is so large that applications should never encounter it.

构造函数

LockRecursionException()

使用说明错误的系统提供的消息初始化 LockRecursionException 类的新实例。Initializes a new instance of the LockRecursionException class with a system-supplied message that describes the error.

LockRecursionException(SerializationInfo, StreamingContext)

使用序列化数据初始化 LockRecursionException 类的新实例。Initializes a new instance of the LockRecursionException class with serialized data.

LockRecursionException(String)

使用说明错误的指定消息初始化 LockRecursionException 类的新实例。Initializes a new instance of the LockRecursionException class with a specified message that describes the error.

LockRecursionException(String, Exception)

使用指定的错误消息和对作为此异常原因的内部异常的引用来初始化 LockRecursionException 类的新实例。Initializes a new instance of the LockRecursionException class with a specified error message and a reference to the inner exception that is the cause of this exception.

属性

Data

获取键/值对的集合,这些键/值对提供有关该异常的其他用户定义信息。Gets a collection of key/value pairs that provide additional user-defined information about the exception.

(继承自 Exception)
HelpLink

获取或设置指向与此异常关联的帮助文件链接。Gets or sets a link to the help file associated with this exception.

(继承自 Exception)
HResult

获取或设置 HRESULT(一个分配给特定异常的编码数字值)。Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception.

(继承自 Exception)
InnerException

获取导致当前异常的 Exception 实例。Gets the Exception instance that caused the current exception.

(继承自 Exception)
Message

获取描述当前异常的消息。Gets a message that describes the current exception.

(继承自 Exception)
Source

获取或设置导致错误的应用程序或对象的名称。Gets or sets the name of the application or the object that causes the error.

(继承自 Exception)
StackTrace

获取调用堆栈上的即时框架字符串表示形式。Gets a string representation of the immediate frames on the call stack.

(继承自 Exception)
TargetSite

获取引发当前异常的方法。Gets the method that throws the current exception.

(继承自 Exception)

方法

Equals(Object)

确定指定对象是否等于当前对象。Determines whether the specified object is equal to the current object.

(继承自 Object)
GetBaseException()

当在派生类中重写时,返回 Exception,它是一个或多个并发的异常的根本原因。When overridden in a derived class, returns the Exception that is the root cause of one or more subsequent exceptions.

(继承自 Exception)
GetHashCode()

用作默认哈希函数。Serves as the default hash function.

(继承自 Object)
GetObjectData(SerializationInfo, StreamingContext)

当在派生类中重写时,用关于异常的信息设置 SerializationInfoWhen overridden in a derived class, sets the SerializationInfo with information about the exception.

(继承自 Exception)
GetType()

获取当前实例的运行时类型。Gets the runtime type of the current instance.

(继承自 Exception)
MemberwiseClone()

创建当前 Object 的浅表副本。Creates a shallow copy of the current Object.

(继承自 Object)
ToString()

创建并返回当前异常的字符串表示形式。Creates and returns a string representation of the current exception.

(继承自 Exception)

事件

SerializeObjectState

当异常被序列化用来创建包含有关该异常的徐列出数据的异常状态对象时会出现该问题。Occurs when an exception is serialized to create an exception state object that contains serialized data about the exception.

(继承自 Exception)

适用于

另请参阅