Asp.Net WebClient  ile request örnekleri için aşağıdaki kodları kullanabilirsiniz.

Asp.net WebClient  Post

string param = "{"data1":"value1","data2":"value2"}";
 string url = "http://api/service";
            using (var client = new WebClient())
            {
                client.Headers.Add("content-type", "application/json");
                string response = Encoding.ASCII.GetString(client.UploadData(url, "POST", Encoding.UTF8.GetBytes(param)));
            }

Asp.net WebClient Put

string param = "{"data1":"value1","data2":"value2"}";
 string url = "http://api/service";
            using (var client = new WebClient())
            {
                client.Headers.Add("content-type", "application/json");
                string response = client.UploadString(url, "PUT", param);
            }

Asp.net WebClient Delete

string url = "http://api/service";
            using (var client = new WebClient())
            {
                client.Headers.Add("content-type", "application/json");
               var response = Encoding.ASCII.GetString(client.UploadValues(url, "DELETE", new NameValueCollection()));
            }

Asp.net WebClient Get

string url = "http://api/service";
 using (var client = new WebClient())
         {
                    client.Headers.Add("content-type", "application/json");
                    string response = client.DownloadString(url);
         }

Eğer WebClient Request basic authentication yapmanızı isterse burdaki yazımızdan faydalanabilirsiniz.