HttpWebRequest.Connection Property
Gets or sets the value of the Connection HTTP header.
Assembly: System (in System.dll)
Property Value
Type: System.StringThe value of the Connection HTTP header. The default value is null.
| Exception | Condition |
|---|---|
| ArgumentException | The value of Connection is set to Keep-alive or Close. |
The request sends the Connection property to the Internet resource as the Connection HTTP header. If the value of the KeepAlive property is true, the value "Keep-alive" is appended to the end of the Connection header.
To clear the Connection HTTP header, set the Connection property to null.
Changing the Connection property after the request has been started by calling the GetRequestStream, BeginGetRequestStream, GetResponse, or BeginGetResponse method throws an InvalidOperationException.
Note |
|---|
The value for this property is stored in WebHeaderCollection. If WebHeaderCollection is set, the property value is lost. |
The following code example uses the Connection property to set the value of the Connection HTTP Header.
Class HttpWebRequest_Connection Shared Sub Main() Try ' Create a new 'HttpWebRequest' object for the specified Uri. Make sure that ' a default proxy is set if you are behind a firewall. Dim myHttpWebRequest1 As HttpWebRequest = CType(WebRequest.Create("http://www.contoso.com"), HttpWebRequest) myHttpWebRequest1.KeepAlive = False ' Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable. Dim myHttpWebResponse1 As HttpWebResponse = CType(myHttpWebRequest1.GetResponse(), HttpWebResponse) Console.WriteLine(ControlChars.Cr + "The HTTP request Headers for the first request are {0}", myHttpWebRequest1.Headers) Console.WriteLine("Press Enter Key to Continue..........") Console.Read() Dim streamResponse As Stream = myHttpWebResponse1.GetResponseStream() Dim streamRead As New StreamReader(streamResponse) Dim readBuff(256) As [Char] Dim count As Integer = streamRead.Read(readBuff, 0, 256) Console.WriteLine("The contents of the Html page are......." + ControlChars.Cr) While count > 0 Dim outputData As New [String](readBuff, 0, count) Console.Write(outputData) count = streamRead.Read(readBuff, 0, 256) End While ' Close the Stream object. streamResponse.Close() streamRead.Close() ' Release the resources held by response object. myHttpWebResponse1.Close() Console.WriteLine() ' Create a new 'HttpWebRequest' object to the specified Uri. Dim myHttpWebRequest2 As HttpWebRequest = CType(WebRequest.Create("http://www.contoso.com"), HttpWebRequest) myHttpWebRequest2.Connection = "Close" ' Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable. Dim myHttpWebResponse2 As HttpWebResponse = CType(myHttpWebRequest2.GetResponse(), HttpWebResponse) ' Release the resources held by response object. myHttpWebResponse2.Close() Console.WriteLine(ControlChars.Cr + "The Http RequestHeaders are " + ControlChars.Cr + "{0}", myHttpWebRequest2.Headers) Console.WriteLine(ControlChars.Cr + "Press 'Enter' Key to Continue.........") Console.Read() Catch e As ArgumentException Console.WriteLine(ControlChars.Cr + "The second HttpWebRequest object has raised an Argument Exception as 'Connection' Property is set to 'Close'") Console.WriteLine(ControlChars.Cr + "{0}", e.Message) Catch e As WebException Console.WriteLine("WebException raised!") Console.WriteLine(ControlChars.Cr + "{0}", e.Message) Console.WriteLine(ControlChars.Cr + "{0}", e.Status) Catch e As Exception Console.WriteLine("Exception raised!") Console.WriteLine("Source :{0} ", e.Source) Console.WriteLine("Message : {0}", e.Message) End Try End Sub ' Main End Class ' HttpWebRequest_Connection
Available since 1.1
