CRUD operations in SharePoint 2013 using REST and C#.Net

Below is CRUD operations on a SharePoint list using Rest and C#
to get this working replace site with your site name
here i am using ContactList for CRUD operations


using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Runtime.Serialization.Json;
using System.Text;
using System.Xml;
namespace REST
{
    class Program
    {
        static string sharepointUrl = "http://Site/_api/web/Lists/getByTitle('ContactList')/items";
       public static Stream postStream;
       public static string results;
       public static string newFormDigest;

        static void Main(string[] args)
        {
            GetItems();
            PostItems();
            UpdateItems();
            DeleteItem();

         
        }

        private static void DeleteItem()
        {
             //184 in the below url is Item ID of a list
            Uri uri = new Uri("http://Site/_api/web/lists/GetByTitle('ContactList')/items(184)");
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
            request.ContentType = "application/json;odata=verbose";
            request.Headers["X-RequestDigest"] = RequestDigestValue(out postStream, out results, out newFormDigest);
            request.Headers["X-HTTP-Method"] = "DELETE";
            request.Headers["IF-MATCH"] = "*";
            request.Credentials = CredentialCache.DefaultCredentials;
            request.Accept = "application/json;odata=verbose";
            request.Method = "POST";
            request.ContentLength = 0;
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            StreamReader reader = new StreamReader(response.GetResponseStream());
        }

        private static void UpdateItems()
        {
         
            Uri uri = new Uri("http://Site/_api/web/lists/GetByTitle('ContactList')/items(185)");
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
            request.ContentType = "application/json;odata=verbose";
            request.Headers["X-RequestDigest"] = RequestDigestValue(out postStream, out results, out newFormDigest);
            request.Headers["X-HTTP-Method"] = "MERGE";
            request.Headers["IF-MATCH"] = "*";
            request.Credentials = CredentialCache.DefaultCredentials;
            request.Accept = "application/json;odata=verbose";
            request.Method = "POST";
            string stringData = "{'__metadata':{'type':'SP.Data.ContactListListItem'}, 'Title':'Jaffa','Street':'Mystreet','City':'Chennai'}";
           // string stringData = "{ '__metadata': { 'type': 'SP.List' }, 'Title': 'New title' }";
            request.ContentLength = stringData.Length;
            StreamWriter writer = new StreamWriter(request.GetRequestStream());
            writer.Write(stringData);
            writer.Flush();

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            StreamReader reader = new StreamReader(response.GetResponseStream());
        }
        public Uri WebUri { get; private set; }
        private static void PostItems()
        {
            // 1st request to get the context information

         
            newFormDigest= RequestDigestValue(out postStream, out results, out newFormDigest);

            Uri webUri = new Uri("http://Site/");
       
            var digestRequest = new Uri(webUri, string.Format("/_api/web/lists/getbytitle('{0}')/items", "ContactList"));
            HttpWebRequest spNewRequest = (HttpWebRequest)HttpWebRequest.Create(digestRequest);
            CredentialCache credNewCache = new CredentialCache();

            //credNewCache.Add(new Uri(digestRequest), "NTLM", CredentialCache.DefaultNetworkCredentials);
            credNewCache.Add(digestRequest, "NTLM", CredentialCache.DefaultNetworkCredentials);
            spNewRequest.Credentials = credNewCache;
            spNewRequest.Method = "POST";
            spNewRequest.Accept = "application/json;odata=verbose";
            spNewRequest.ContentType = "application/json;odata=verbose";
            spNewRequest.Headers.Add("X-RequestDigest", newFormDigest);
            string listPostBody = "{'__metadata':{'type':'SP.Data.ContactListListItem'}, 'Title':'MyTitle','Street':'MystreetName','City':'Delhi'}";
   


            // For Content Length

            byte[] postByte = Encoding.UTF8.GetBytes(listPostBody);
            spNewRequest.ContentLength = postByte.Length;
            Stream postStreamBody = spNewRequest.GetRequestStream();
            postStreamBody.Write(postByte, 0, postByte.Length);
            postStreamBody.Close();
            HttpWebResponse webResponse = (HttpWebResponse)spNewRequest.GetResponse();
            results = GetHTTPResponse(webResponse, out postStream, out results);

        }

        private static string RequestDigestValue(out Stream postStream, out string results, out string newFormDigest)
        {
            string formdigestRequest = "http://Site/_api/contextinfo";
            CredentialCache credCache = new CredentialCache();
            credCache.Add(new Uri(formdigestRequest), "NTLM", CredentialCache.DefaultNetworkCredentials);
            HttpWebRequest spRequest = (HttpWebRequest)HttpWebRequest.Create(formdigestRequest);

            spRequest.Credentials = credCache;
            spRequest.Method = "POST";
            spRequest.Accept = "application/json;odata=verbose";
            spRequest.ContentLength = 0;


            HttpWebResponse endpointResponse = (HttpWebResponse)spRequest.GetResponse();
            results = GetHTTPResponse(endpointResponse, out postStream, out results);



            // Get the FormDigest Value

            var startTag = "FormDigestValue";
            var endTag = "LibraryVersion";
            var startTagIndex = results.IndexOf(startTag) + 1;
            var endTagIndex = results.IndexOf(endTag, startTagIndex);
            newFormDigest = null;
            if ((startTagIndex >= 0) && (endTagIndex > startTagIndex))
            {

                newFormDigest = results.Substring(startTagIndex + startTag.Length + 2, endTagIndex - startTagIndex - startTag.Length - 5);

            }
            return newFormDigest;
        }
        private static String GetHTTPResponse(HttpWebResponse endpointResponse, out  Stream postStream, out  string results)
        {
            postStream = endpointResponse.GetResponseStream();
            StreamReader postReader = new StreamReader(postStream);
            results = postReader.ReadToEnd();
            postReader.Close();
            postStream.Close();
            return results;
        }
        private static void GetItems()
        {
           //Replace "Site" with your site name
            HttpWebRequest endpointRequest = (HttpWebRequest)HttpWebRequest.Create("http://Site/_api/web/Lists/getByTitle('ContactList')/items");

            endpointRequest.Method = "GET";
            endpointRequest.Accept = "application/json;odata=verbose";
            NetworkCredential cred = new System.Net.NetworkCredential("UserName", "Password", "Domain");
            endpointRequest.Credentials = cred;
            HttpWebResponse endpointResponse = (HttpWebResponse)endpointRequest.GetResponse();
            try
            {
                WebResponse webResponse = endpointRequest.GetResponse();
                Stream webStream = webResponse.GetResponseStream();
                StreamReader responseReader = new StreamReader(webStream);
                string response = responseReader.ReadToEnd();
                JObject jobj = JObject.Parse(response);
                JArray jarr = (JArray)jobj["d"]["results"];

                foreach (JObject j in jarr)
                {
                    //City and County are column names in a list
                    Console.WriteLine(j["City"] + "  " + j["County"]);

                }

                responseReader.Close();
                Console.ReadLine();

            }
            catch (Exception e)
            {
                Console.Out.WriteLine(e.Message); Console.ReadLine();
            }
        }
    }

}