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PipeStream.BeginRead(Byte[], Int32, Int32, AsyncCallback, Object) Method

Definition

Begins an asynchronous read operation.

public:
 override IAsyncResult ^ BeginRead(cli::array <System::Byte> ^ buffer, int offset, int count, AsyncCallback ^ callback, System::Object ^ state);
public override IAsyncResult BeginRead (byte[] buffer, int offset, int count, AsyncCallback? callback, object? state);
public override IAsyncResult BeginRead (byte[] buffer, int offset, int count, AsyncCallback callback, object state);
[System.Security.SecurityCritical]
public override IAsyncResult BeginRead (byte[] buffer, int offset, int count, AsyncCallback callback, object state);
override this.BeginRead : byte[] * int * int * AsyncCallback * obj -> IAsyncResult
[<System.Security.SecurityCritical>]
override this.BeginRead : byte[] * int * int * AsyncCallback * obj -> IAsyncResult
Public Overrides Function BeginRead (buffer As Byte(), offset As Integer, count As Integer, callback As AsyncCallback, state As Object) As IAsyncResult

Parameters

buffer
Byte[]

The buffer to read data into.

offset
Int32

The byte offset in buffer at which to begin reading.

count
Int32

The maximum number of bytes to read.

callback
AsyncCallback

The method to call when the asynchronous read operation is completed.

state
Object

A user-provided object that distinguishes this particular asynchronous read request from other requests.

Returns

An IAsyncResult object that references the asynchronous read.

Attributes

Exceptions

buffer is null.

offset is less than 0.

-or-

count is less than 0.

count is greater than the number of bytes available in buffer.

The pipe is closed.

The pipe does not support read operations.

The pipe is disconnected, waiting to connect, or the handle has not been set.

The pipe is broken or another I/O error occurred.

Remarks

Pass the returned IAsyncResult object to the EndRead method to determine how many bytes were read and to release operating system resources used for reading. EndRead must be called once for every call to BeginRead. This can be done either in the same code that called BeginRead or in a callback that is passed to BeginRead.

Use the CanRead property to determine whether the current PipeStream object supports read operations.

If the pipe is closed or an invalid argument is passed to BeginRead, the appropriate exceptions are raised immediately. Errors that occur during an asynchronous read request occur on the thread pool thread that is performing the request. The exceptions are raised when the code calls the EndRead method.

Applies to