Clearing children deletes parent - asp.net-mvc-3

I have three related tables. Calendar 1...* CalendarUser *...1 User. When I have edited the CalendarUsers in the edit calendar view I then post the ViewModel back to the controller. Here is my controller code:
[HttpPost]
public ActionResult Edit(int id, CreateCalendarViewModel cvm)
{
long userId = long.Parse(User.Identity.Name);
db.Calendars.Attach(cvm.CurrentCalendar);
cvm.Users= DbExtensions.GetUserList(userId);
if (ModelState.IsValid)
{
////Remove the deselected users
cvm.CurrentCalendar.CalendarUsers.Clear();
//Get the names from the selected users
var selectedUsers = from u in cvm.Users
where cvm.SelectedUsers.Contains(u.Key)
select new KeyValuePair<long, string>(long.Parse(u.Key), u.Value);
foreach (var selectedUser in selectedUsers)
{
User user = db.Users.Find(selectedUser.Key);
//If usr does not exist create a new
if (user == null)
{
db.Users.Add(new User
{
UserId = selectedUser.Key,
Name = selectedUser.Value,
Expires = DateTime.Now,
AccessToken = string.Empty
});
}
//Add the binding to the calendar
cvm.CurrentCalendar.CalendarUsers.Add(new CalendarUser
{
CalendarId = cvm.CurrentCalendar.CalendarId,
UserId = selectedUser.Key
});
}
db.Entry(cvm.CurrentCalendar).State = EntityState.Modified;
db.SaveChanges();
}
return View(cvm);
}
Here are my classes:
public partial class Calendar
{
public Calendar()
{
this.CalendarUsers = new HashSet<CalendarUser>();
}
public int CalendarId { get; set; }
public string CalendarTitle { get; set; }
public string CalendarDescription { get; set; }
public long UserId { get; set; }
public virtual User User { get; set; }
public virtual ICollection<CalendarUser> CalendarUsers { get; set; }
}
public partial class CalendarUser
{
public int CalendarUserId { get; set; }
public int CalendarId { get; set; }
public long UserId { get; set; }
public Nullable<bool> IsAdmin { get; set; }
public virtual Calendar Calendar { get; set; }
public virtual User User { get; set; }
}
public partial class User
{
public User()
{
this.Calendars = new HashSet<Calendar>();
this.CalendarUsers = new HashSet<CalendarUser>();
}
public long UserId { get; set; }
public string Name { get; set; }
public virtual ICollection<Calendar> Calendars { get; set; }
public virtual ICollection<CalendarUser> CalendarUsers { get; set; }
}
For some reason when i save the changes the calendar is being deleted as well? I've searched a bit but noone seem to have the same problem? Am I doing it wrong? Is there a better way to update/remove related entities?

It seems that I forgot to include a hidden field in in the view containing the id of the user and the result was that when I updated the calendar it saved with Id = 0 and thus hid the objects in the view for the specified user. Mental note: Always verify in the database what is really happening.
I also need to look into whats happening when I send objects back and forth between views and controller. Sometimes it seems to manage by itself and sometimes I need to specify all the fields myself.

Related

Reference built-in Account UserId Assign to Model as Foreign Key

after looking for an answer in the already existing questions, I am still a little confused as how I should proceed. I am new to the MVC 3 framework, so if I come off sounding like a dope, I appologize!!
Ok, so I created a MVC 3 internet application, created 3 new Users administrator, user1, and user2. I have created a new model, and controller for my "Posts" I am able to add, edit and delete the items. I currently have a column called UserID in my posts table. I would like this to be automagically populated with the current UsersID. I think I would define this in the controller like this:
[HttpPost]
public ActionResult Create(Post post)
{
if (ModelState.IsValid)
{
public int User = System.Web.Security.Membership.GetUser(id);
db.Posts.Add(post);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(post);
}
Inside the model, this is what I currently have:
public class Post
{
public int PostID { get; set; }
public int UserID { get; set; }
public string PostTitle { get; set; }
public int PostType { get; set; }
public string PostBody { get; set; }
public string PostBlogTitle { get; set; }
public string PostBlogURL { get; set; }
public string PostCategory { get; set; }
public string PostSEO { get; set; }
public int PostStatus { get; set; }
}
public class PostDBContext : DbContext
{
public DbSet<Post> Posts { get; set; }
}
I would like to replace public int UserID { get; set; } with my newly defined variable in the controller, but not sure where/how to add it.
Not sure I'm clear on what you're trying to achieve. Are you just trying to assign the current user to the model, save it and then pass it back to the view?
If so you can just do this:
[HttpPost]
public ActionResult Create(Post post)
{
if (ModelState.IsValid)
{
// Note: I'm assuming this actually works/returns an int
public int User = System.Web.Security.Membership.GetUser(id);
post.UserID = User;
db.Posts.Add(post);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(post);
}

Multiple Parent models for a child model

I'm creating an MVC3 asp.net application using Entity Framework 4 and C#.
I've tried to read up on EF and model binding, lazy loading, etc. But I've hit an obstacle.
I have a User Model. The Store and UserType models can have an ICollection of Users. When I add a User with the Create Action, How do I specify multiple parents?
I think that I only know how to add if there is one parent.
My Models:
public class UserType
{
public virtual int ID { get; set; }
public virtual string UserTypeName { get; set; }
public virtual ICollection<User> Users { get; set; }
}
public class Store
{
public virtual int ID { get; set; }
public virtual string StoreName { get; set; }
public virtual Address StoreAddress { get; set; }
public virtual ICollection<Workroom> Workrooms { get; set;}
public virtual ICollection<User> Users { get; set; }
}
public class User
{
public virtual int ID { get; set; }
public virtual string Username { get; set; }
public virtual string Email { get; set; }
public virtual Store Store { get; set; }
public virtual UserType UserType { get; set; }
}
Here is my db context:
public DbSet<Workroom> Workrooms { get; set; }
public DbSet<Ticket> Tickets { get; set; }
public DbSet<Customer> Customers { get; set; }
public DbSet<Store> Stores { get; set; }
public DbSet<User> Users { get; set; }
public DbSet<UserType> UserTypes { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Store>()
.HasMany(store => store.Workrooms)
.WithRequired(workroom => workroom.Store);
modelBuilder.Entity<Store>()
.HasMany(store => store.Users)
.WithRequired(user => user.Store);
modelBuilder.Entity<UserType>()
.HasMany(usertype => usertype.Users)
.WithRequired(user => user.UserType);
base.OnModelCreating(modelBuilder);
}
Here's my create action:
public ActionResult Create()
{
return View(new User());
}
//
// POST: /Users/Create
[HttpPost]
public ActionResult Create(User newUser)
{
try
{
int storeID = newUser.Store.ID;
var store = _db.Stores.Single(r => r.ID == storeID);
store.Users.Add(newUser);
_db.SaveChanges();
return RedirectToAction("Index");
}
catch (Exception ex)
{
ModelState.AddModelError("", ex.InnerException.Message);
return View();
}
}
Do I just add another "Add" call for UserType? for example:
int userTypeID = newUser.UserType.ID
var usertype = _db.UserTypes.Single(s => s.ID == userTypeID)
How would the Entity Framework know that Users has another Parent??? ...do I care?
My hunch is that I should be doing this a different way, more specific and more accurate.
In this case, you probably want to add the user to the Users table, rather than the Stores. Then you assign the StoreID and UserTypeID to the user before you commit.
It looks like you're already setting the StoreID in your UI, are you doing the same for UserType? If so, then just add the user to the users table and you should be good.

asp.net mvc3 UpdateModel exclude properties is not working

I have a class, which has 8 props / 8 columns in DB. But on a Edit page, i dont want to show the AddedDate or UserID field, since i dont want user to change it.
public class Voucher
{
public int ID { get; set; }
public string Title { get; set; }
public string SiteName { get; set; }
public string DealURL { get; set; }
public DateTime AddedDate { get; set; }
public DateTime? ExpirationDate { get; set; }
public string VoucherFileURL { get; set; }
public Guid UserID { get; set; }
}
Here is what I have for Edit controller:
// POST: /Voucher/Edit/5
[HttpPost]
public ActionResult Edit(Voucher voucher)
{
if (ModelState.IsValid)
{
string[] excludeProperties = { "AddedDate", "UserID" };
UpdateModel(ModelState, "", null, excludeProperties);
db.Entry(voucher).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
}
return View(voucher);
}
On Edit page, once i click on submit, i got the following error: System.Data.SqlServerCe.SqlCeException: An overflow occurred while converting to datetime.
Seems like the AddedDate didn't get excluded from the view model and triggered the error.
Would you please let me know how to fix it? Thanks!
public ActionResult Edit([Bind(Exclude = "AddedDate")]Voucher voucher)
no luck either
You are still passing in Voucher which could contain that field in it. I'm not sure what you are trying to accomplish with the UpdateModel here if you are already passing in a Voucher object?
Pass in Voucher, set it to modified and save it. If you want to use whats in the database then you'll have to
Load the object from the database
UpdateModel and exclude the properties
Save your entity.
You could simply use a View Model and post that.
public class Voucher
{
public int ID { get; set; }
public string Title { get; set; }
public string SiteName { get; set; }
public string DealURL { get; set; }
public DateTime? ExpirationDate { get; set; }
public string VoucherFileURL { get; set; }
public Guid UserID { get; set; }
}
and then load up your object from the db":
var voucher = db.Vouchers.Where(o=>o.ID==voucherViewModel.Id);
//manually copy the fields here then save it
//copy
db.SaveChanges();

Create with ViewModel that has two related entities

I have the properties for two entities in a ViewModel. The two entities are both related to one another, so for example, User and Posts. Each User can have multiple Posts, and Many Posts can belong to a single user (one-to-many).
The aim from my ViewModel is to allow the addition of a User and a Post on the same form. So my ViewModel looks something like this:
public class CreateVM
{
[Required, MaxLength(50)]
public string Username { get; set; }
[Required, MaxLength(500), MinLength(50)]
public string PostBody { get; set; }
// etc with some other related properties
}
In my Controller on the Create Method I have something like this:
[HttpPost]
public ActionResult Create(CreateVM vm)
{
if (ModelState.IsValid)
{
User u = new User()
{
Username = vm.Username,
// etc populate properties
};
Post p = new Post()
{
Body = vm.PostBody,
// etc populating properties
};
p.User = u; // Assigning the new user to the post.
XContext.Posts.Add(p);
XContext.SaveChanges();
}
}
It all looks fine when I walk through it through the Debugger, but when I try to view the post, its User relationship is null!
I also tried
u.Posts.Add(p);
UPDATE:
My Post class code is as follows:
public class Post
{
[Key]
public int Id { get; set; }
[Required, MaxLength(500)]
public string Body { get; set; }
public int Likes { get; set; }
[Required]
public bool isApproved { get; set; }
[Required]
public DateTime CreatedOn { get; set; }
[Required]
public User User { get; set; }
}
But that also did not work. What am I doing wrong?
Problem is that EF can not lazy load the User property because you haven't made it virtual.
public class Post
{
[Key]
public int Id { get; set; }
[Required, MaxLength(500)]
public string Body { get; set; }
public int Likes { get; set; }
[Required]
public bool isApproved { get; set; }
[Required]
public DateTime CreatedOn { get; set; }
[Required]
public virtual User User { get; set; }
}
If you know beforehand that you are going to access the User property of the post you should eager load the User related to the post.
context.Posts.Include("User").Where(/* condition*/);

Relationships on mvc3 entity code first

My project has two objects: users and meetings
Every meeting has one user that is the "head" of the meeting and a many users that are simple.
My models are these:
public class Meeting
{
public int MeetingId { get; set; }
public string Title { get; set; }
public virtual User User { get; set; }
public Location From { get; set; }
public Location To { get; set; }
public virtual ICollection<User> Users { get; set; }
}
public class Location
{
public float Lat { get; set; }
public float Long { get; set; }
}
public class User
{
public int UserId { get; set; }
public string Name { get; set; }
public string Email { get; set; }
}
I created a controller for the meeting model. Now every time that i add another meeting a and in the user field i put an existing userid this user is not inserted and new user is created.
What's wrong?
edit
the create controller
[HttpPost]
public ActionResult Create(Tremp tremp)
{
if (ModelState.IsValid)
{
db.Tremps.Add(tremp);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(tremp);
}
in the form i just enter the id of the user
I'm no expert on EF code first, but your code example did cause some deja vu for me. I think the problem is that you need to configure the relationship between the "head" user and the meeting e.g.
public class Meeting
{
public int MeetingId { get; set; }
public string Title { get; set; }
[ForeignKey("UserId")]
public virtual User User { get; set; }
[Column(name: "UserId")]
public int HeaderUserId { get; set; }
public Location From { get; set; }
public Location To { get; set; }
public virtual ICollection<User> Users { get; set; }
}
If your tremp entity has a reference to an existing user (tremp.User) you must attach this user to the context before you add the tremp. This tells EF that this user is existing in the database and avoids to insert a new user:
[HttpPost]
public ActionResult Create(Tremp tremp)
{
if (ModelState.IsValid)
{
db.Users.Attach(tremp.User);
db.Tremps.Add(tremp);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(tremp);
}

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