Information
The topic you requested is included in another documentation set. For convenience, it's displayed below. Choose Switch to see the topic in its original location.

Socket.Available Property

Gets the amount of data that has been received from the network and is available to be read.

Namespace: System.Net.Sockets
Assembly: System (in system.dll)

public int Available { get; }
/** @property */
public int get_Available ()

public function get Available () : int

Not applicable.

Property Value

The number of bytes of data received from the network and available to be read.

Exception typeCondition

SocketException

An error occurred when attempting to access the socket. See the Remarks section for more information.

ObjectDisposedException

The Socket has been closed.

If you are using a non-blocking Socket, Available is a good way to determine whether data is queued for reading, before calling Receive. The available data is the total amount of data queued in the network buffer for reading. If no data is queued in the network buffer, Available returns 0.

If the remote host shuts down or closes the connection, Available can throw a SocketException. If you receive a SocketException, use the SocketException.ErrorCode property to obtain the specific error code. After you have obtained this code, refer to the Windows Sockets version 2 API error code documentation in the MSDN library for a detailed description of the error.

NoteNote:

This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing.

The following code example compares the results of calling IOControl with FIONREAD and the Available property.

 // FIONREAD is also available as the "Available" property.
public const int FIONREAD   = 0x4004667F;

static void DisplayPendingByteCount(Socket s)
 {
     byte[] outValue = BitConverter.GetBytes(0);

     // Check how many bytes have been received.
     s.IOControl(FIONREAD, null, outValue);
     
     uint bytesAvailable = BitConverter.ToUInt32(outValue, 0);
     Console.WriteLine("server has {0} bytes pending. Available property says {1}.",
         bytesAvailable, s.Available);
     
     return;
 }

// FIONREAD is also available as the "Available" property.
public static final int FIONREAD = 0x4004667F;

static void DisplayPendingByteCount(Socket s)
{
    ubyte outValue[] = BitConverter.GetBytes(0);
    // Check how many bytes have been received.
    s.IOControl(FIONREAD, null, outValue);

    UInt32 bytesAvailable = BitConverter.ToUInt32(outValue, 0);
    //ToDo: Unsigned Integers not supported- converted to int
    Console.WriteLine("server has {0} bytes pending. Available property "
        + "says {1}.", bytesAvailable.ToString(), 
        (System.Int32)s.get_Available());
    return;
} //DisplayPendingByteCount

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0
Was this page helpful?
(1500 characters remaining)
Thank you for your feedback

Community Additions

Show:
© 2014 Microsoft