C# HttpWebRequest 多网卡指定IP下载

/// <summary>
        /// 获取指定网卡IP
        /// </summary>
        /// <param name="servicePoint"></param>
        /// <param name="remoteEndPoint"></param>
        /// <param name="retryCount"></param>
        /// <returns></returns>
        public IPEndPoint BindIPEndPointCallback(ServicePoint servicePoint, IPEndPoint remoteEndPoint, int retryCount)
        {
            if (!string.IsNullOrWhiteSpace(_configuration.IP))
            {
                IPAddress address = IPAddress.Parse(_configuration.IP);
                return new IPEndPoint(address, 0);
            }
            return new IPEndPoint(IPAddress.Any, 0);
        }
public static void Main()
{
    HttpWebRequest request = (HttpWebRequest) WebRequest.Create("http://MyServer");
    request.ServicePoint.BindIPEndPointDelegate = new BindIPEndPoint(BindIPEndPointCallback);
    HttpWebResponse response = (HttpWebResponse)request.GetResponse();
}