In ASP.NET the Page class exposes a Request property which provides access to a QueryString property - this is a NameValueCollection that lets you get values out in much the same way as in your existing example, by specifying keys:
var id = Page.Request.QueryString("id"); var newQuery = string.Format("?member_id=15893&id={0}&", id);
The above can easily be expanded to build more into your required query string.
As for the request you're initiating, that can be achieved using a WebRequest instance; to alter the sample from MSDN only slightly, here is an example:
WebRequest request = WebRequest.Create(yourUrl + newQuery); HttpWebResponse response = (HttpWebResponse)request.GetResponse(); Response.Write(response.StatusDescription); Stream dataStream = response.GetResponseStream(); StreamReader reader = new StreamReader (dataStream); string responseFromServer = reader.ReadToEnd(); Response.Write(responseFromServer); reader.Close(); dataStream.Close(); response.Close();