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PowerTCP Email Validation for .NET |
| Dart.PowerTCP.EmailValidation Namespace > DatagramEventArgs Class : Exception Property (DatagramEventArgs) |
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PowerTCP Email Validation for .NET |
| Dart.PowerTCP.EmailValidation Namespace > DatagramEventArgs Class : Exception Property (DatagramEventArgs) |
Gets any exception which occurred during the asynchronous operation.
[Visual Basic]
Public ReadOnly Property Exception As Exception[C#]
public Exception Exception {get;}[C++]
public: __property Exception* get_Exception();If any exception occurred during the asynchronous operation, this property will contain an Exception object describing the exception.
Check this property to tell if an exception occurred during the asynchronous operation. If this property is null, no exception occurred.
The exception property is useful for checking exceptions and handling them appropriately. For example, if a bad command was sent to the server, a ProtocolException may be thrown. You could check this property to see if it was of type ProtocolException, than handle appropriately.
The following example demonstrates creating a UDP echo server application which listens for datagrams and echoes them back to the sender.
[Visual Basic]
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
' Listen for datagrams on port 7.
Udp1.Open(7)
' Begin an asynchronous Receive
Dim buffer(Udp1.BufferSize) As Byte
Udp1.BeginReceive(buffer)
End Sub
Private Sub Udp1_EndReceive(ByVal sender As Object, ByVal e As DatagramEventArgs) Handles Udp1.EndReceive
' Check for an Exception
If e.Exception is Nothing Then
' Echo the data back using the Datagram object passed into the event.
' Datagram.Buffer = data received from client
' Datagram.RemoteEndPoint = address/port of client.
Udp1.Send(e.Datagram.Buffer, e.Datagram.RemoteEndPoint)
End If
' Start receiving next
Dim buffer(Udp1.BufferSize) As Byte
Udp1.BeginReceive(buffer)
End Sub
[C#]
private void StartServer()
{
// Listen for datagrams on port 7.
udp1.Open(7);
// Begin an asynchronous Receive
byte[] buffer = new byte[udp1.BufferSize];
udp1.BeginReceive(buffer);
}
private void udp1_EndReceive(object
sender, DatagramEventArgs e)
{
// Check for an exception
if(e.Exception == null)
{
// Echo the data back using the Datagram object passed into the event.
// Datagram.Buffer = data received from client
// Datagram.RemoteEndPoint = address/port of client.
Datagram d = udp1.Send(e.Datagram.Buffer, e.Datagram.RemoteEndPoint);
}
// Start receiving next
byte[] buffer = new byte[udp1.BufferSize];
udp1.BeginReceive(buffer);
}
Platforms: Windows 98, Windows NT 4.0, Windows ME, Windows 2000, Windows XP, Windows Server 2003, Windows Vista
DatagramEventArgs Class | DatagramEventArgs Members
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Documentation version 1.0.3.0.
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