Gets or sets a value indicating whether the server requests a persistent connection.
Assembly: System (in System.dll)
Public Property KeepAlive As Booleanpublic bool KeepAlive { get; set; }public:
property bool KeepAlive {
bool get ();
void set (bool value);
}member KeepAlive : bool with get, set
Property Value
Type: Systemtrue if the server requests a persistent connection; otherwise, false. The default is true.
| Exception | Condition |
|---|---|
| ObjectDisposedException | This object is closed. |
If an HTTP client and server expect to exchange data multiple times in a short period, a persistent connection speeds up their communications by allowing them to avoid the overhead required to open and close a TCP connection for each message. Persistent connections are in widespread use in communications between modern Web browsers and Web servers.
Persistent connections are described in detail in the HTTP/1.1 protocol specification (RFC 2616) available at the RTF Editor Web site (http://www.rfc-editor.org).
The following code example demonstrates setting the value of this property.
' When the client is not authenticated, there is no Identity.
If context.User Is Nothing Then
message.Append("<HTML><BODY><p> Hello local user! </p></BODY></HTML>")
Else
' Get the requester's identity.
Dim identity As System.Security.Principal.WindowsIdentity = WindowsIdentity.GetCurrent()
' Construct the response body.
message.AppendFormat("<HTML><BODY><p> Hello {0}!<br/>", identity.Name)
message.AppendFormat("You were authenticated using {0}.</p>", identity.AuthenticationType)
message.Append("</BODY></HTML>")
End If
' Configure the response.
Dim response As HttpListenerResponse = context.Response
' Use the encoding from the response if one has been set.
' Otherwise, use UTF8.
Dim encoding As System.Text.Encoding = response.ContentEncoding
If encoding Is Nothing Then
encoding = System.Text.Encoding.UTF8
response.ContentEncoding = encoding
End If
Dim buffer() As Byte = encoding.GetBytes(message.ToString())
response.ContentLength64 = buffer.Length
response.StatusCode = CInt(HttpStatusCode.OK)
response.StatusDescription = "OK"
response.ProtocolVersion = New Version("1.1")
' Don't keep the TCP connection alive
' We don't expect multiple requests from the same client.
response.KeepAlive = False
' Write the response body.
Dim stream As System.IO.Stream = response.OutputStream
stream.Write(buffer, 0, buffer.Length)
// When the client is not authenticated, there is no Identity.
if (context.User == null)
{
message.Append ("<HTML><BODY><p> Hello local user! </p></BODY></HTML>");
}
else
{
// Get the requester's identity.
System.Security.Principal.WindowsIdentity identity = WindowsIdentity.GetCurrent();
// Construct the response body.
message.AppendFormat ("<HTML><BODY><p> Hello {0}!<br/>",
identity.Name);
message.AppendFormat ("You were authenticated using {0}.</p>",
identity.AuthenticationType);
message.Append ("</BODY></HTML>");
}
// Configure the response.
HttpListenerResponse response = context.Response;
// Use the encoding from the response if one has been set.
// Otherwise, use UTF8.
System.Text.Encoding encoding = response.ContentEncoding;
if (encoding == null)
{
encoding = System.Text.Encoding.UTF8;
response.ContentEncoding = encoding;
}
byte[] buffer = encoding.GetBytes (message.ToString ());
response.ContentLength64 = buffer.Length;
response.StatusCode = (int) HttpStatusCode.OK;
response.StatusDescription = "OK";
response.ProtocolVersion = new Version ("1.1");
// Don't keep the TCP connection alive;
// We don't expect multiple requests from the same client.
response.KeepAlive = false;
// Write the response body.
System.IO.Stream stream = response.OutputStream;
stream.Write(buffer, 0, buffer.Length);
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.