IEmployee.cs

public interface IEmployee
{
  List<EmployeeData> GetAllEmployees();

  EmployeeData GetEmployeeById(int EmpId);

  bool InsertEmployee(EmployeeData emp);

  bool UpdateEmployee(EmployeeData emp);

  bool DeleteEmployee(int EmpId);
}


public class Employee : IEmployee
{
  private EmployeeContext dbContext = new EmployeeContext();

  public List<EmployeeData> GetAllEmployees()
  {
    var data = (from c in dbContext.EmployeeData
                select c).ToList();

    return data;
  }

  public EmployeeData GetEmployeeById(int EmpId)
  {
    var data = (from c in dbContext.EmployeeData
                where c.EmpId == EmpId
                select c).FirstOrDefault();

    return data;
  }

  public bool InsertEmployee(EmployeeData emp)
  {
    dbContext.EmployeeData.Add(emp);
    if (dbContext.SaveChanges() > 0)
    {
      return true;
    }
    else
    {
      return false;
    }
  }

  public bool UpdateEmployee(EmployeeData emp)
  {
    var data = (from c in dbContext.EmployeeData where c.EmpId == emp.EmpId select c).FirstOrDefault();

    data.EmpName = emp.EmpName;
    data.DOB = emp.DOB;

    if (dbContext.SaveChanges() > 0)
    {
      return true;
    }
    else
    {
      return false;
    }
  }

  public bool DeleteEmployee(int EmpId)
  {
    var data = (from c in dbContext.EmployeeData where c.EmpId == EmpId select c).FirstOrDefault();
    dbContext.EmployeeData.Remove(data);
    if (dbContext.SaveChanges() > 0)
    {
      return true;
    }
    else
    {
      return false;
    }
  }
}