Set Method (String, String)

WebHeaderCollection.Set Method (String, String)

 

Sets the specified header to the specified value.

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

Public Overrides Sub Set (
	name As String,
	value As String
)

Parameters

name
Type: System.String

The header to set.

value
Type: System.String

The content of the header to set.

Exception Condition
ArgumentNullException

name is null or Empty.

ArgumentOutOfRangeException

The length of value is greater than 65535.

ArgumentException

name is a restricted header.

-or-

name or value contain invalid characters.

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

If the header specified in header is already present, value replaces the existing value.

The following example uses the Set method to set the value of an existing header.

   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

           'Set the Cache-Control header in the request.
           myWebHeaderCollection.Set("Cache-Control", "no-cache")

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

    Console.WriteLine ("Headers after 'Set' method is used on Cache-Control :")
           'Print the headers for the request.
           PrintHeaders(myWebHeaderCollection)
           myHttpWebResponse.Close()
      'Catch exception if trying to set 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
Available since 1.1
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