如何提高代码质量以及如何减少未使用的对象？

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using FirstLevel.Models.ObjectGroup;
using FirstLevel.ServiceReference2;
using System.ComponentModel;
using System.Xml.Serialization;
using System.Runtime.Serialization;
using System.ServiceModel;
using Valentica.Libraries;

namespace FirstLevel.Controllers
{
    public class RightsController : Controller
    {
        //
        // GET: /Rights/
        Service1Client sc = new Service1Client();
        ObjectGroup ob = new ObjectGroup();
        public ActionResult Index(int? pageid, int? pagesize)
        {
            if (sc.State == CommunicationState.Closed)
            {
                sc.Open();
            }

            List<SelectListItem> rolename = new List<SelectListItem>();
            rolename.Add(new SelectListItem() { Text = "---Select Role---", Value = "0", Selected = true });
            var listR = sc.GetRoleName();
            foreach (var x in listR)
            {
                rolename.Add(new SelectListItem() { Text = x.Rolname, Value = x.Rolid.ToString() });
            }
            ViewData["Rolebind"] = null;
            ViewData["Rolebind"] = rolename;
            var listG = sc.Getobjectdetails();
            sc.Close();
            string dt = "";
            foreach (var r in listG)
            {
                dt += r.ObjectId + "!";
            }
            ob.Objectnos = dt;
            ViewData["Objectgroupdata"] = listG;
           
             return View(ob);
        }
        [HttpPost]
        public ActionResult Index(ObjectGroup og)
        {
            int roleid = 0;
            roleid = og.RoleID;
            sc.Open();
            if (!string.IsNullOrEmpty(og.divdetails))
            {
                string[] arr = og.divdetails.Split('$');
                for (int i = 0; i < arr.Length; i++)
                {
                    if (!string.IsNullOrEmpty(arr[i]))
                    {
                        string[] arr1 = arr[i].Split('!');
                        int objno = Convert.ToInt32(arr1[0]);
                        sc.DeleteExistingRights(objno, roleid);
                        
                        if (arr1[1] == "Y" || arr1[2] == "Y" || arr1[3] == "Y" || arr1[4] == "Y")
                        {
                            CompositeObjectGroup co = new CompositeObjectGroup();
                            co.RoleId = roleid;
                            co.ObjectId = objno;
                            if (arr1[1] == "Y")
                            { co.Delete = true; }
                            else { co.Delete = false; }
                            if (arr1[2] == "Y")
                            { co.All = true; }
                            else { co.All = false; }
                            if (arr1[1] == "Y")
                            { co.Add = true; }
                            else { co.Add = false; }
                            if (arr1[1] == "Y")
                            { co.Edit = true; }
                            else { co.Edit = false; }
                            if (arr1[1] != "Y" && arr1[2] != "Y" && arr1[3] != "Y" && arr1[4] != "Y")
                            {
                                co.All = true;
                            }
                            else
                            {
                                co.All = false;
                            }
                            co.CreatedOn = DateTime.Now.Date;
                            co.createdby  = Convert.ToInt32(Session["UserID"].ToString());
                            sc.AddRightsdata(co);
                        }
                    }
                }
                sc.Close();
            }       
            return RedirectToAction("Index");
        }
        [AcceptVerbs(HttpVerbs.Get)]
        public JsonResult GetData(int id)
        {
           // RT rht = new RT();
            short rid = (short)Convert.ToInt32(id);
            string dt = "";
            sc.Open();
            var obj = sc.Getobjectdetails().OrderBy(x => x.GroupId);
            var Sub = sc.GetRightslist(rid);
            foreach (var K in obj)
            {
                string flag = "N";
                dt += K.ObjectId + "!";
                foreach (var D in Sub)
                {
                    if (K.ObjectId == D.ObjectId)
                    {
                        dt += D.Delete + "!";
                        dt += D.Edit+ "!";
                        dt += D.Add + "!";
                        dt += D.All + "$";
                        flag = "Y";
                    }
                }
                if (flag == "N")
                {
                    dt += "N!";
                    dt += "N!";
                    dt += "N!";
                    dt += "N$";
                }
            }
            return Json(dt, JsonRequestBehavior.AllowGet);
        }
    }


}