Handling Created and Modified Date in MVC - asp.net

Question

HI i have an MVC application which have CreatedDate and ModifiedDate feilds,
1. CreatedDate is when user create the module(any entry)
2. ModifiedDate is when user Edit the module
I have following Model class
namespace MyForms.Models
{
public class Master
{
public int ID { get; set; }
public string ModuleName { get; set; }
public int CreatedBy { get; set; }
public DateTime ? CreatedDate { get; set; }
public int ModifyBy { get; set; }
public DateTime ModifyDate { get; set; }
public Boolean IsActive { get; set; }
public Boolean IsDeleted { get; set; }
// public virtual ICollection<Master> MasterModules { get; set; }
}
public class MyFormDemoContext : DbContext
{
public DbSet<Master> MasterForms { get; set;}
}
}
Actions of Create and Edit
public ActionResult Create()
{
return View();
}
[HttpPost]
public ActionResult Create(Master master)
{
try
{
using (MyFormDemoContext context = new MyFormDemoContext())
{
master.CreatedBy = 1;
master.CreatedDate = DateTime.Now;
var a = master.CreatedDate;
master.IsActive = true;
master.ModifyBy = 1;
master.ModifyDate = DateTime.Now;
master.IsDeleted = false;
context.MasterForms.Add(master);
context.SaveChanges();
}
return RedirectToAction("Index");
}
catch
{
return View();
}
}
public ActionResult Edit(int id)
{
using (MyFormDemoContext context = new MyFormDemoContext())
{
return View(context.MasterForms.Find(id));
}
}
//
// POST: /Home/Edit/5
[HttpPost]
public ActionResult Edit(int id, Master valpara)
{
try
{
using (MyFormDemoContext context = new MyFormDemoContext())
{
valpara.CreatedBy = 1;
valpara.CreatedDate = DateTime.Now;
valpara.IsActive = true;
valpara.ModifyBy = 1;
valpara.ModifyDate = DateTime.Now;
valpara.IsDeleted = false;
valpara.ModifyDate = DateTime.Now;
context.Entry(valpara).State = System.Data.EntityState.Modified;
context.SaveChanges();
}
return RedirectToAction("Index");
}
catch
{
return View();
} }
1.currently when i create the module(entry) createdDate goes as current date
2. When i edit the module, modifiedDate and createdDate goes same
My expections
I want the createdDate Remains same when i Modify or edit the entry only modified date will be updated

Answer 1

When i edit the module, modifiedDate and createdDate goes same
Well, that's because in your Edit action you are specifically setting the CreatedDate, remove this line
valpara.CreatedDate = DateTime.Now
and only the ModifiedDate will be updated. However, a better approach would be to have your DB configured to set the date automatically (e.g. if you are using MSSQL set the default value to GetUtcDate()) and have EF pull that value instead of setting it client-side.
You need to set DatabaseGeneratedOption.Identity on that particular field which tells EF that the DB will generate the value.
FYI - you should really consider storing your dates as UTC rather than local i.e. use DateTime.UtcNow rather than DateTime.Now.
As well as the above, in your Edit you are actually re-creating a new entry each time. If you want to modify an existing record then you need to pull that record out of the DB first e.g.
using (MyFormDemoContext context = new MyFormDemoContext())
{
var record = context.MasterForms.SingleOrDefault(x => x.ID == id);
if (record != null)
{
record.ModifyBy = 1;
record.ModifyDate = DateTime.UtcNow;
context.SaveChanges();
}
}