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Hi 
please help me out to create the string builder to create a campaign. 
I use the following string builder to create a contact list. Do i need to create the string builder in the same way. Please advice me. Please send me a modal if you don't mind.
 
 
private string CreateaContactList(string sUserName, string sPassWord, string Listame) //success
    {
    //https://api.constantcontact.com/ws/customers/{username}/campaigns 
        string sCampUri = "https://api.constantcontact.com/ws/customers/" + sUserName + "/lists";
        string sAPIKey = "84325c7d-79ae-4754-aeeb-788006cc0745";
        Uri address = new Uri(sCampUri);
        HttpWebRequest request = WebRequest.Create(address) as HttpWebRequest;
        request.Credentials = new NetworkCredential((sAPIKey + "%" + sUserName), sPassWord);
        request.Method = "POST";
        request.ContentType = "application/atom+xml";
        //atom+xml";
        StringBuilder data = new StringBuilder();
 
        data.Append(@"<entry xmlns=""http://www.w3.org/2005/Atom"">");
        data.Append(@"<id>data:,</id>");
        data.Append(@"<title/>");
        data.Append(@"<author/>");
        data.Append(@"<updated>" +System.DateTime.Now.ToString()+"</updated>");
        data.Append(@"<content type=""application/vnd.ctct+xml"">");
        data.Append(@"<ContactList xmlns=""http://ws.constantcontact.com/ns/1.0/"">");
        data.Append(@"<OptInDefault>false</OptInDefault>");
        data.Append(@"<Name>" + Listame + "</Name>");
        data.Append(@"<SortOrder>92</SortOrder>");
        data.Append(@"</ContactList>");
        data.Append(@"</content>");
        data.Append(@"</entry>");
        //Email Address,Email Type,First Name,Last Name
        byte[] byteData = UTF8Encoding.UTF8.GetBytes(data.ToString());
        string st = String.Empty;
        request.ContentLength = byteData.Length;
        using (Stream postStream = request.GetRequestStream())
        {
            postStream.Write(byteData, 0, byteData.Length);
        }
        
            using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
            {
                // Get the response stream  
                StreamReader reader = new StreamReader(response.GetResponseStream());
                st = reader.ReadToEnd();
            }
return st;
        }
Thanks in advance,
Pradeep