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WebHeaderCollection.Remove Method (String)

Removes the specified header from the collection.

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

'Declaration
Public Overrides Sub Remove ( _
	name As String _
)

Parameters

name
Type: System.String

The name of the header to remove from the collection.

ExceptionCondition
ArgumentNullException

name is Nothing Empty.

ArgumentException

name is a restricted header.

-or-

name contains invalid characters.

Remove deletes the specified header from the collection. If the specified header does not exist, the method returns.

The following example uses the Remove method to remove a header from the WebHeaderCollection. After the header is removed, this example prints all existing headers to the screen to prove that it has been removed.

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.
        myWebHeaderCollection.Set("Cache-Control", "no-cache")

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

        'Print the headers of the request to console.
        Console.WriteLine("Print request headers after adding Cache-Control for first request")
        printHeaders(myHttpWebRequest.Headers)


        'Remove the Cache-Control header for the new request.
        myWebHeaderCollection.Remove("Cache-Control")

        'Code example for "Remove" method of "WebHeaderCollection" ends here. 
        'Get the response for the new request.
        myHttpWebResponse = CType(myHttpWebRequest.GetResponse(), HttpWebResponse)

        'Print the headers of the new request without the Cache-Control header.
        Console.WriteLine("Print request headers after removing Cache-Control for the new request")
        printHeaders(myHttpWebRequest.Headers)
        myHttpWebResponse.Close()
    'Catch exception if trying to remove a restricted header. 
    Catch e As ArgumentException
        Console.WriteLine("Error : Trying to remove a restricted header")
        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: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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