ReaderWriterLockSlim.TryEnterReadLock Method

Definition

Tries to enter the lock in read mode, with an optional time-out.

Overloads

TryEnterReadLock(Int32)

Tries to enter the lock in read mode, with an optional integer time-out.

TryEnterReadLock(TimeSpan)

Tries to enter the lock in read mode, with an optional time-out.

TryEnterReadLock(Int32)

Tries to enter the lock in read mode, with an optional integer time-out.

public:
 bool TryEnterReadLock(int millisecondsTimeout);
public bool TryEnterReadLock (int millisecondsTimeout);
member this.TryEnterReadLock : int -> bool
Public Function TryEnterReadLock (millisecondsTimeout As Integer) As Boolean

Parameters

millisecondsTimeout
Int32

The number of milliseconds to wait, or -1 (Infinite) to wait indefinitely.

Returns

true if the calling thread entered read mode, otherwise, false.

Exceptions

The RecursionPolicy property is NoRecursion and the current thread has already entered the lock.

-or-

The recursion number would exceed the capacity of the counter. The limit is so large that applications should never encounter it.

The value of millisecondsTimeout is negative, but it is not equal to Infinite (-1), which is the only negative value allowed.

The ReaderWriterLockSlim object has been disposed.

Remarks

If millisecondsTimeout is 0 (zero), this method checks the lock state and returns false immediately if the desired state is unavailable.

Multiple threads can enter read mode at the same time.

If one or more threads are waiting to enter write mode, a thread that calls the TryEnterReadLock method blocks until those threads have either timed out or entered write mode and then exited from it, or until the calling thread's own time-out interval expires.

Note

If a lock allows recursion, a thread that has entered the lock in read mode can enter read mode recursively, even if other threads are waiting to enter write mode.

One thread can be in upgradeable mode while other threads are in read mode. If additional threads are waiting to enter upgradeable mode, and there are no threads waiting to enter write mode, threads that call the TryEnterReadLock method enter read mode immediately and do not block.

TryEnterReadLock(TimeSpan)

Tries to enter the lock in read mode, with an optional time-out.

public:
 bool TryEnterReadLock(TimeSpan timeout);
public bool TryEnterReadLock (TimeSpan timeout);
member this.TryEnterReadLock : TimeSpan -> bool
Public Function TryEnterReadLock (timeout As TimeSpan) As Boolean

Parameters

timeout
TimeSpan

The interval to wait, or -1 milliseconds to wait indefinitely.

Returns

true if the calling thread entered read mode, otherwise, false.

Exceptions

The RecursionPolicy property is NoRecursion and the current thread has already entered the lock.

-or-

The recursion number would exceed the capacity of the counter. The limit is so large that applications should never encounter it.

The value of timeout is negative, but it is not equal to -1 milliseconds, which is the only negative value allowed.

-or-

The value of timeout is greater than MaxValue milliseconds.

The ReaderWriterLockSlim object has been disposed.

Remarks

If timeout is 0 (zero), this method checks the lock state and returns false immediately if the desired state is unavailable.

Multiple threads can enter the lock in read mode at the same time.

If one or more threads are queued to enter write mode, a thread that calls the TryEnterReadLock method blocks until those threads have either timed out or entered write mode and then exited from it, or until the calling thread's own time-out interval expires.

Note

If a lock allows recursion, a thread that has entered the lock in read mode can enter read mode recursively, even if other threads are waiting to enter write mode.

One thread can be in upgradeable mode while other threads are in read mode. If additional threads are waiting to enter upgradeable mode, and there are no threads waiting to enter write mode, threads that call the TryEnterReadLock method enter read mode immediately and do not block.

Applies to