This documentation is archived and is not being maintained.

WebHeaderCollection.Add Method (String, String)

Inserts a header with the specified name and value into the collection.

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

'Declaration
Public Overrides Sub Add ( _
	name As String, _
	value As String _
)

Parameters

name
Type: System.String
The header to add to the collection.
value
Type: System.String
The content of the header.

ExceptionCondition
ArgumentException

name is Nothing, Empty, or contains invalid characters.

-or-

name is a restricted header that must be set with a property setting.

-or-

value contains invalid characters.

ArgumentOutOfRangeException

The length of value is greater than 65535.

If the header specified in name does not exist, the Add method inserts a new header into the list of header name/value pairs.

If the header specified in name is already present, value is added to the existing comma-separated list of values associated with name.

The following example adds a name/value pair to a WebHeaderCollection using the Add Method.


    Public Shared Sub Main()

     Try
            'Create a web request for "www.msn.com".
            Dim myHttpWebRequest As HttpWebRequest = CType(WebRequest.Create("http://www.msn.com"), HttpWebRequest)

            'Get the headers associated with the request.
            Dim myWebHeaderCollection As WebHeaderCollection = myHttpWebRequest.Headers

   	    Console.WriteLine("Configuring Webrequest to accept Danish and English language using 'Add' method")

	    'Add the Accept-Language header (for Danish) in the request.
            myWebHeaderCollection.Add("Accept-Language:da")

            'Include English in the Accept-Langauge header. 
            myWebHeaderCollection.Add("Accept-Language","en;q" + ChrW(61) + "0.8")

            'Get the associated response for the above request.
            Dim myHttpWebResponse As HttpWebResponse = CType(myHttpWebRequest.GetResponse(), HttpWebResponse)

            'Print the headers for the request.
            printHeaders(myWebHeaderCollection)
            myHttpWebResponse.Close()
        'Catch exception if trying to add a restricted header.
        Catch e As ArgumentException
            Console.WriteLine(e.Message)
        Catch e As WebException
            Console.WriteLine(e.Message)
            If e.Status = WebExceptionStatus.ProtocolError Then
                Console.WriteLine("Status Code : {0}", CType(e.Response, HttpWebResponse).StatusCode)
                Console.WriteLine("Status Description : {0}", CType(e.Response, HttpWebResponse).StatusDescription)
                Console.WriteLine("Server : {0}", CType(e.Response, HttpWebResponse).Server)
            End If
        Catch e As Exception
            Console.WriteLine(e.Message)
        End Try
    End Sub 'Main


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

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.
Show: