how to create simple mvc CRUD in asp.net using json

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;

namespace MvcCrud.Controllers
{
public class HomeController : Controller
{
public TraineeDemoEntities edc = new TraineeDemoEntities();


public ActionResult index()
{

return RedirectToAction("Employee");
}

public ActionResult Employee()
{

return View();

}

public string SaveEmployee(decimal id, string Name, string Address)
{
string msg = "";

if (id == 0)
{
var e1 = new Student();
e1.Name = Name;
e1.Address = Address;
e1.Isactive = 1;
edc.Students.AddObject(e1);
msg = "Insert Successfully ";
edc.SaveChanges();
}
else
{
Student s1 = edc.Students.SingleOrDefault(t => t.Sid == id);
s1.Name = Name;
s1.Address = Address;
s1.Isactive = 1;
msg = "Update Successfully";
edc.SaveChanges();
}

return msg;
}

public JsonResult EditStudent(decimal id)
{
var objstud = edc.Students.Where(t => t.Sid == id).ToList();
return Json(objstud, JsonRequestBehavior.AllowGet);
}

public JsonResult BindStudent()
{
var objstud = edc.Students.Where(t => t.Isactive == 1).ToList();
return Json(objstud, JsonRequestBehavior.AllowGet);
}

public string DelStudent(int id)
{
string flg = "";
try
{
Student objstu = edc.Students.Where(t => t.Sid == id).SingleOrDefault();
if (objstu != null)
{
objstu.Isactive = 0;
edc.SaveChanges();
flg = "true";
}
}
catch (Exception ex)
{
throw ex;
}
return flg;
}
}
}