WebHeaderCollection.Remove Method (String)

 

Removes the specified header from the collection.

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

Public Overrides Sub Remove (
	name As String
)

Parameters

name
Type: System.String

The name of the header to remove from the collection.

Exception Condition
ArgumentNullException

name is nullEmpty.

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

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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