Action<string> lambda - use Sub not Function?

[James]

auth = new WebAuthorizer
        {
            Credentials = credentials,
            PerformRedirect = authUrl => Response.Redirect(authUrl)
        };

converts to:

auth = New WebAuthorizer() With { _
    .Credentials = credentials, _
    .PerformRedirect = Function(authUrl) Response.Redirect(authUrl) _
}

Function should be replaced with Sub?