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IInputChannel.BeginTryReceive(TimeSpan, AsyncCallback, Object) Method

Definition

Begins an asynchronous operation to receive a message that has a specified time out and state object associated with it.

public:
 IAsyncResult ^ BeginTryReceive(TimeSpan timeout, AsyncCallback ^ callback, System::Object ^ state);
public IAsyncResult BeginTryReceive (TimeSpan timeout, AsyncCallback callback, object state);
abstract member BeginTryReceive : TimeSpan * AsyncCallback * obj -> IAsyncResult
Public Function BeginTryReceive (timeout As TimeSpan, callback As AsyncCallback, state As Object) As IAsyncResult

Parameters

timeout
TimeSpan

The TimeSpan that specifies the interval of time to wait for a message to become available.

callback
AsyncCallback

The AsyncCallback delegate that receives the notification of the asynchronous operation completion.

state
Object

An object, specified by the application, that contains state information associated with the asynchronous operation.

Returns

The IAsyncResult that references the asynchronous receive operation.

Exceptions

The specified timeout is exceeded before the operation is completed.

The timeout specified is less than zero.

Examples

The following code illustrates how to implement this method:

public IAsyncResult BeginTryReceive(TimeSpan timeout, AsyncCallback callback, object state)
{
    TryReceiveAsyncResult<TChannel> result = new TryReceiveAsyncResult<TChannel>(this, timeout, callback, state);
    result.Begin();
    return result;
}

Remarks

Use the asynchronous BeginTryReceive(TimeSpan, AsyncCallback, Object) method when you want the application processing to continue without waiting. Use the synchronous TryReceive(TimeSpan, Message) method when it is acceptable for the current thread to be blocked while it replies to the request message or until the timeout interval is exceeded.

The operation is not complete until either a message becomes available in the channel or the timeout occurs.

If you are going to handle timeouts and not just re-throw or wrap the TimeoutException, then you should call BeginTryReceive(TimeSpan, AsyncCallback, Object) instead of BeginReceive.

If you are not going to treat timeouts specially then just call BeginReceive, otherwise you lose error information.

Notes to Implementers

The operation returns false from EndTryReceive(IAsyncResult, Message) if the specified timeout is exceeded.

Applies to