CRUD Operations in MVC 5 - asp.net

Question

I am developing an application in MVC 5 and perform CRUD operations on it.
I have successfully added Northwind database as an Entity Data Model and taking Customer in the Model. Now with the help of Scaffolding I generated the CustomersController.
When I create a new record in a Customer Table. There is no problem.
But when I click on that new record, Edit, Details and Delete are not working. After clicking any of these:
The following page occurs:
My Controller Code:
namespace MvcNorthwindSample.Controllers
{
public class CustomersController : Controller
{
private NORTHWNDEntities db = new NORTHWNDEntities();
// GET: Customers
public ActionResult Index()
{
return View(db.Customers.ToList());
}
// GET: Customers/Details/5
public ActionResult Details(string id)
{
if (id == null)
{
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
}
Customer customer = db.Customers.Find(id);
if (customer == null)
{
return HttpNotFound();
}
return View(customer);
}
// GET: Customers/Create
public ActionResult Create()
{
return View();
}
// POST: Customers/Create
// To protect from overposting attacks, please enable the specific properties you want to bind to, for
// more details see http://go.microsoft.com/fwlink/?LinkId=317598.
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Create([Bind(Include = "CustomerID,CompanyName,ContactName,ContactTitle,Address,City,Region,PostalCode,Country,Phone,Fax")] Customer customer)
{
if (ModelState.IsValid)
{
db.Customers.Add(customer);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(customer);
}
// GET: Customers/Edit/5
public ActionResult Edit(string id)
{
if (id == null)
{
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
}
Customer customer = db.Customers.Find(id);
if (customer == null)
{
return HttpNotFound();
}
return View(customer);
}
// POST: Customers/Edit/5
// To protect from overposting attacks, please enable the specific properties you want to bind to, for
// more details see http://go.microsoft.com/fwlink/?LinkId=317598.
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Edit([Bind(Include = "CustomerID,CompanyName,ContactName,ContactTitle,Address,City,Region,PostalCode,Country,Phone,Fax")] Customer customer)
{
if (ModelState.IsValid)
{
db.Entry(customer).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
}
return View(customer);
}
// GET: Customers/Delete/5
public ActionResult Delete(string id)
{
if (id == null)
{
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
}
Customer customer = db.Customers.Find(id);
if (customer == null)
{
return HttpNotFound();
}
return View(customer);
}
// POST: Customers/Delete/5
[HttpPost, ActionName("Delete")]
[ValidateAntiForgeryToken]
public ActionResult DeleteConfirmed(string id)
{
Customer customer = db.Customers.Find(id);
db.Customers.Remove(customer);
db.SaveChanges();
return RedirectToAction("Index");
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
db.Dispose();
}
base.Dispose(disposing);
}
}
}
My View Part:
My Create Code Result view while debugging:

Answer 1

EDIT: After you posted your controller:
Customer customer = db.Customers.Find(id);
if (customer == null)
{
return HttpNotFound();
}
Are you sure that you have a customer with an id of 1994? If not, your logic would return HttpNotFound().
In the screenshot you posted, I can read HTTP 404 error message and the requested URL was /Customer/Edit/1994.
So for that I assume you must be have the following controller/action:
public class CustomerController
{
public ActionResult Edit(int id)
{
return View();
}
}
Now the most common mistake most people make (including me) is properly passing id in the URL. You have id specified as an optional parameter in your route pattern:
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
So if you don't want to use id you could pass something else as a key name in the the query component, e.g., /Customer/Edit?year=1994.

Answer 2

The error is a 404 Error.
It is looking in the Controller Customers for an Edit action.
Also pointed out in the comments the Id 1994 has a encoded space character following it. If the id is suppose to be strings, you can change the parameter to type string instead of int
public class CustomersController
{
public ActionResult Edit(int id)
{
return View();
}
}

Answer 3

I solved it. I changed the table at last. There is a problem on the table named Customers of the Northwind database. I download database backup file. The Customer ID column is adding a space as a default with the inserted value.

Answer 4

First create your models and Dbcontext.
public class TaskManagerContext : DbContext
{
public TaskManagerContext()
: base("TaskManagerDB")
{
}
public DbSet<User> Users { get; set; }
public DbSet<Task> Tasks { get; set; }
}
Then allow migrations and update the database from the PM. Create a folder Repositories with a BaseRepo that the rest must inherit.
public class BaseRepository<T> where T:BaseModel, new()
{
protected TaskManagerContext context;
protected DbSet<T> dbSet;
public BaseRepository()
{
this.context = new TaskManagerContext();
this.dbSet = this.context.Set<T>();
}
public void Insert(T item)
{
this.dbSet.Add(item);
this.context.SaveChanges();
}
public void Update(T item)
{
this.context.Entry(item).State = EntityState.Modified;
this.context.SaveChanges();
}
public void Delete(int id)
{
this.dbSet.Remove(this.dbSet.Find(id));
this.context.SaveChanges();
}
public IEnumerable<T> GetAll()
{
return this.dbSet;
}
}
like this:
public class UsersRepository : BaseRepository<User>
{
public UsersRepository()
: base()
{
}
}
Then you create the controllers in which you use the methods from the repos.
public class UsersController : Controller
{
//
// GET: /Users/
public ActionResult List()
{
List<User> users = new List<User>();
users = new UsersRepository().GetAll().ToList();
return View(users);
}
public ActionResult Edit(int id)
{
User user = new UsersRepository().GetAll().FirstOrDefault(u => u.ID == id);
return View(user);
}
[HttpPost]
public ActionResult Edit(User user)
{
UsersRepository repo = new UsersRepository();
repo.Update(user);
return RedirectToAction("List");
}
public ActionResult Delete(int id)
{
UsersRepository repo = new UsersRepository();
repo.Delete(id);
return RedirectToAction("List");
}
public ActionResult Create()
{
User u = new User();
return View(u);
}
[HttpPost]
public ActionResult Create(User user)
{
UsersRepository repo = new UsersRepository();
repo.Insert(user);
return RedirectToAction("List");
}
}
The actions for the TaskContr are simillar exept the List in which you connect the 2 models by ID:
public ActionResult List(int? id)
{
TasksRepository repo = new TasksRepository();
List<Task> tasks = new List<Task>();
tasks = repo.GetAll().Where(t => t.UserID == id).ToList();
return View(tasks);
}
Don't forget to generate views(on the Get methods) and change the List view for the Users:
#Html.ActionLink("Details", "List", "Tasks", new { id=item.ID }, null) |
That way when clicking Details you can see the tasks for that user.

Answer 5

public ActionResult Index()
{
using (DevExam db = new DevExam())
{
var intern = from m in db.Interns
select m;
return View(intern.ToList());
}
/* using (DevExam db = new DevExam())
{
var interns = db.Interns
.Include(s => s.InternID)
.Select(s => new Intern
{
InternID = s.InternID,
lname = s.lname,
fname = s.fname
});
return View(interns);
}
*/
}
// GET: CRUD/Details/5
public ActionResult Details(int id)
{
using (DevExam db = new DevExam())
{
return View(db.Interns.Where(x => x.InternID == id).FirstOrDefault());
}
}
// GET: CRUD/Create
public ActionResult Create()
{
return View();
}
// POST: CRUD/Create
[HttpPost]
public ActionResult Create(Intern intern)
{
try
{
// TODO: Add insert logic here
using (DevExam db = new DevExam())
{
db.Interns.Add(intern);
db.SaveChanges();
}
return RedirectToAction("Index");
}
catch
{
return View();
}
}
// GET: CRUD/Edit/5
public ActionResult Edit(int id)
{
using (DevExam db = new DevExam())
{
return View(db.Interns.Where(x => x.InternID == id).FirstOrDefault());
}
}
// POST: CRUD/Edit/5
[HttpPost]
public ActionResult Edit(int id,Intern intern)
{
try
{
// TODO: Add update logic here
using (DevExam db = new DevExam())
{
db.Entry(intern).State = EntityState.Modified;
db.SaveChanges();
}
return RedirectToAction("Index");
}
catch
{
return View();
}
}
// GET: CRUD/Delete/5
public ActionResult Delete(int id)
{
using (DevExam db = new DevExam())
{
return View(db.Interns.Where(x => x.InternID == id).FirstOrDefault());
}
}
// POST: CRUD/Delete/5
[HttpPost]
public ActionResult Delete(int id, FormCollection collection)
{
try
{
// TODO: Add delete logic here
using (DevExam db = new DevExam())
{
Intern intern = db.Interns.Where(x => x.InternID == id).FirstOrDefault();
db.Interns.Remove(intern);
db.SaveChanges();
}
return RedirectToAction("Index");
}
catch
{
return View();
}
}

Answer 6

create table tblemployee(
EmpId int NOT NULL identity(1,1),
EmpName varchar(100),
PhoneNumber varchar(10),
Country int,
State int,
maritalstetus varchar(50),
isvoting varchar(50),
dob datetime,
doj datetime
primary key (EmpId)
)
create table tblCountry(
Id int NOT NULL identity(1,1),
Name varchar(100),
primary key (Id)
)
insert into tblCountry(Name) values ('India')
insert into tblCountry(Name) values ('US')
insert into tblCountry(Name) values ('UK')
create table tblstate(
Id int NOT NULL identity(1,1),
Name varchar(100),
countryId int,
primary key (Id)
)
insert into tblstate(Name ,countryId) values ('Delhi',1)
insert into tblstate(Name , countryId) values ('Bihar' ,1)
insert into tblstate(Name , countryId) values ('Up',1)
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;
using System.Xml.Linq;
namespace webTest.Models
{
public class Employee
{
public int id { get; set; }
[Required]
public string Name { get; set; }
[Required]
public string PhoneNumber { get; set; }
[Required]
public int Country { get; set; }
[Required]
public int State { get; set; }
[Required]
public bool MarritalStatus { get; set; }
public bool IsVoting { get; set; }
[Required]
[DataType(DataType.Date)]
public DateTime DOB { get; set; }
[Required]
[DataType(DataType.Date)]
public DateTime DOJ { get; set; }
}
}
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using webTest.Models;
namespace webTest.Controllers
{
public class EmpController : Controller
{
// GET: Emp
public static string constr = "Data Source=DIVYANSHU;Initial Catalog=EmployeeData;Integrated Security=True";
SqlConnection conn = new SqlConnection(constr);
public ActionResult ViewList()
{
List<Employee> employees = new List<Employee>();
try
{
conn.Open();
string sqlquery = "select * from tblEmployee";
SqlCommand cmd = new SqlCommand(sqlquery, conn);
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
Employee emp = new Employee()
{
id = Convert.ToInt32(dr["Empid"].ToString().Trim()),
Name = dr["EmpName"].ToString(),
PhoneNumber = dr["PhoneNumber"].ToString(),
Country = Convert.ToInt32(dr["Country"].ToString().Trim()),
State = Convert.ToInt32(dr["State"].ToString().Trim()),
MarritalStatus = Convert.ToBoolean(dr["maritalstetus"].ToString().Trim()),
IsVoting = Convert.ToBoolean(dr["isvoting"]),
DOB = Convert.ToDateTime(dr["dob"].ToString().Trim()),
DOJ = Convert.ToDateTime(dr["doj"].ToString().Trim()),
};
employees.Add(emp);
}
conn.Close();
}
catch (Exception ex)
{
}
return View(employees);
}
public ActionResult Create()
{
SqlDataAdapter _da = new SqlDataAdapter("Select * From tblCountry", constr);
DataTable _dt = new DataTable();
_da.Fill(_dt);
ViewBag.Country = ToSelectList(_dt, "Id", "Name");
_da.Dispose();
SqlDataAdapter _da1 = new SqlDataAdapter("Select * From tblState", constr);
DataTable _dt1 = new DataTable();
_da1.Fill(_dt1);
ViewBag.State = ToSelectList(_dt1, "Id", "Name");
_da1.Dispose();
Employee emp = new Employee();
return View(emp);
}
public SelectList ToSelectList(DataTable table, string valueField, string textField)
{
List<SelectListItem> list = new List<SelectListItem>();
foreach (DataRow row in table.Rows)
{
list.Add(new SelectListItem()
{
Text = row[textField].ToString(),
Value = row[valueField].ToString()
});
}
return new SelectList(list, "Value", "Text");
}
[HttpPost]
public ActionResult Create(Employee empmodel)
{
List<Employee> employees = new List<Employee>();
try
{
conn.Open();
string sqlquery = "insert into tblEmployee(EmpName,PhoneNumber,Country,State,maritalstetus,isvoting,dob,doj) values('" + empmodel.Name + "','" + empmodel.PhoneNumber + "'," + empmodel.Country + "," + empmodel.State + ",'" + empmodel.MarritalStatus + "','" + empmodel.IsVoting + "','" + empmodel.DOB + "','" + empmodel.DOJ + "')";
SqlCommand cmd = new SqlCommand(sqlquery, conn);
cmd.ExecuteNonQuery();
conn.Close();
employees = listEmployee();
}
catch (Exception ex)
{
}
return View("ViewList", employees);
}
public ActionResult Edit(int id)
{
Employee emp = new Employee();
try
{
SqlDataAdapter _da = new SqlDataAdapter("Select * From tblCountry", constr);
DataTable _dt = new DataTable();
_da.Fill(_dt);
ViewBag.Country = ToSelectList(_dt, "Id", "Name");
_da.Dispose();
SqlDataAdapter _da1 = new SqlDataAdapter("Select * From tblState", constr);
DataTable _dt1 = new DataTable();
_da1.Fill(_dt1);
ViewBag.State = ToSelectList(_dt1, "Id", "Name");
_da1.Dispose();
conn.Open();
string sqlquery = "select * from tblemployee where empid=" + id + "";
SqlCommand cmd = new SqlCommand(sqlquery, conn);
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
emp = new Employee()
{
id = Convert.ToInt32(dr["Empid"].ToString().Trim()),
Name = dr["EmpName"].ToString(),
PhoneNumber = dr["PhoneNumber"].ToString(),
Country = Convert.ToInt32(dr["Country"].ToString().Trim()),
State = Convert.ToInt32(dr["State"].ToString().Trim()),
MarritalStatus = Convert.ToBoolean(dr["maritalstetus"].ToString().Trim()),
IsVoting = Convert.ToBoolean(dr["isvoting"]),
DOB = Convert.ToDateTime(dr["dob"].ToString().Trim()),
DOJ = Convert.ToDateTime(dr["doj"].ToString().Trim()),
};
}
conn.Close();
}
catch (Exception ex)
{
}
return View(emp);
}
[HttpPost]
public ActionResult Edit(Employee empmodel)
{
try
{
conn.Open();
string sqlquery = "update tblEmployee set EmpName='" + empmodel.Name + "',PhoneNumber='" + empmodel.PhoneNumber + "',Country=" + empmodel.Country + ",State=" + empmodel.State + ",maritalstetus='" + empmodel.MarritalStatus + "',isvoting='" + empmodel.IsVoting + "',dob='" + empmodel.DOB + "',doj='" + empmodel.DOJ + "' where empid=" + empmodel.id + "";
SqlCommand cmd = new SqlCommand(sqlquery, conn);
cmd.ExecuteNonQuery();
conn.Close();
}
catch (Exception ex)
{
}
List<Employee> list = listEmployee();
return View("ViewList", list);
}
public ActionResult Delete(int id)
{
try
{
conn.Open();
string sqlquery = "Delete from tblEmployee where empid=" + id + "";
SqlCommand cmd = new SqlCommand(sqlquery, conn);
cmd.ExecuteNonQuery();
conn.Close();
}
catch (Exception ex)
{
}
List<Employee> list = listEmployee();
return View("ViewList", list);
}
public List<Employee> listEmployee()
{
List<Employee> employees = new List<Employee>();
conn.Open();
string sqlquery = "select * from tblEmployee";
SqlCommand cmd = new SqlCommand(sqlquery, conn);
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
Employee emp = new Employee()
{
id = Convert.ToInt32(dr["Empid"].ToString().Trim()),
Name = dr["EmpName"].ToString(),
PhoneNumber = dr["PhoneNumber"].ToString(),
Country = Convert.ToInt32(dr["Country"].ToString().Trim()),
State = Convert.ToInt32(dr["State"].ToString().Trim()),
MarritalStatus = Convert.ToBoolean(dr["maritalstetus"].ToString().Trim()),
IsVoting = Convert.ToBoolean(dr["isvoting"]),
DOB = Convert.ToDateTime(dr["dob"].ToString().Trim()),
DOJ = Convert.ToDateTime(dr["doj"].ToString().Trim()),
};
employees.Add(emp);
}
conn.Close();
return employees;
}
}
}
//in Edit view and in create view replace edit for to
#Html.DropDownListFor(model => model.Country, ViewBag.Country as SelectList, new { #class = "form-control" })
#Html.DropDownListFor(model => model.State, ViewBag.State as SelectList, new { #class = "form-control" })