I have been struggling with this for several days. I need to populate a dropdownlistfor with genres.
My MovieRepository to grab the genres:
public IQueryable<Movies> MoviesAndGenres
{
get { return db.Movies.Include(m => m.parentGenre); }
}
My movie model
public virtual Genres parentGenre { get; set; }
Genre Model:
public class Genres
{
public Genres()
{
this.movies = new HashSet<Movies>();
}
[Key]
public int genreId { get; set; }
[Required(ErrorMessage = "A genre name is required")]
[StringLength(25)]
public String genreName { get; set; }
public ICollection<Movies> movies { get; set; }
}
I am trying to pass in the genres with a select list, but I am getting a LINQ to Entities does not recognize the System.String To String() Method, and this method cannot be translated to a stored expression.
Movies Controller, addMovie action:
ViewBag.Genres = movieRepository.MoviesAndGenres.Select(m => new SelectListItem
{
Text = m.parentGenre.genreName,
Value = m.parentGenre.genreId.ToString()
}).ToList();
return View();
View:
#Html.DropDownListFor(m => m.parentGenre, (SelectList)ViewBag.Genres)
Any help would be greatly appreciated!
Update:
Repository:
public IQueryable<Genres> MoviesAndGenres
{
get { return db.Genres; }
}
Controller:
var x = movieRepository.MoviesAndGenres.Select(m => new
{
Text = m.genreName,
Value = m.genreId
});
ViewBag.Genres = new SelectList(x);
return View();
View:
#Html.DropDownListFor(m => m.parentGenre, (SelectList)ViewBag.Genres)
Since you're retrieving all of the records anyways, you can just do this.
ViewBag.Genres = movieRepository.MoviesAndGenres.AsEnumerable()
.Select(m => new SelectListItem
{
Text = m.parentGenre.genreName,
Value = m.parentGenre.genreId.ToString()
});
You would also need to change your view to:
#Html.DropDownListFor(m => m.parentGenre, new SelectList(ViewBag.Genres))
Actually, a better approach would probably be this, since then it only retrieves the specific columns you need:
var x = movieRepository.MoviesAndGenres.Select(m => new
{
Text = m.parentGenre.genreName,
Value = m.parentGenre.genreId
});
ViewBag.Genres = new SelectList(x)
Also, the ToList() is no longer required because it's already in a an immediate state.
Related
I want to display related data from second table with each value in first table
i have tried this query
public ActionResult Index()
{
List<EmployeeAtt> empWithDate = new List<EmployeeAtt>();
var employeelist = _context.TblEmployee.ToList();
foreach (var employee in employeelist)
{
var employeeAtt = _context.AttendanceTable
.GroupBy(a => a.DateAndTime.Date)
.Select(g => new EmployeeAtt
{
Date = g.Key,
Emp_name = employee.EmployeeName,
InTime = g.Any(e => e.ScanType == "I") ? g.Where(e =>
e.ScanType == "I").Min(e =>
e.DateAndTime.ToShortTimeString())
.ToString() : "Absent",
OutTime = g.Any(e => e.ScanType == "O") ? g.Where(e =>
e.ScanType == "O").Max(e =>
e.DateAndTime.ToShortTimeString())
.ToString() : "Absent"
});
empWithDate.AddRange(employeeAtt);
}
return View(empWithDate);
}
Here is my attendance Table
AttendanceTable
Results
I want to display the shortest time with "I" Column value against each employee and last time with "O" Column value as out time. I think i am not using AddRange() at proper place. Where it should go then?
public partial class TblEmployee
{
public TblEmployee()
{
AttendanceTable = new HashSet<AttendanceTable>();
}
public int EmpId { get; set; }
public string EmployeeName { get; set; }
public virtual ICollection<AttendanceTable> AttendanceTable { get; set; }
}
public partial class AttendanceTable
{
public int Id { get; set; }
public int AttendanceId { get; set; }
public int EmployeeId { get; set; }
public string ScanType { get; set; }
public DateTime DateAndTime { get; set; }
public virtual TblEmployee Employee { get; set; }
}
The actual problem is not related to AddRange(), you need a where clause before GroupBy() to limit attendances (before grouping) to only records related to that specific employee, e.g.
_context.AttendanceTable
.Where(a => a.Employee == employee.EmployeeName)
.GroupBy(a => a.DateAndTime.Date)
...
Depended on your model, it is better to use some kind of ID instead of EmployeeName for comparison if possible.
Also you can use SelectMany() instead of for loop and AddRange() to combine the results into a single list. like this:
List<EmployeeAtt> empWithDate = _context.TblEmployee.ToList()
.SelectMany(employee =>
_context.AttendanceTable
.Where(a => a.Employee == employee.EmployeeName)
.GroupBy(a => a.DateAndTime.Date)
.Select(g => new EmployeeAtt
{
...
})
);
...
I have a MVC3 Razor form. It have a radiobutton list and some another text fields. When I press submit controller post action get the view model, which have all fields seted correctly, except RegionID.
Model:
namespace SSHS.Models.RecorderModels
{
public class CreateViewModel
{
...
public int RegionID { get; set; }
...
}
}
Controller:
namespace SSHS.Controllers
{
public class RecorderController : Controller
{
...
public ActionResult Create()
{
EntrantDBEntities db = new EntrantDBEntities();
List Regions = new List(db.Region);
List Schools = new List(db.School);
List Settlements = new List(db.settlement);
CreateViewModel newEntr = new CreateViewModel();
ViewBag.Regions = Regions;
ViewBag.Schools = Schools;
ViewBag.Settlements = Settlements;
return View(newEntr);
}
[HttpPost]
public ActionResult Create(CreateViewModel m)
{
EntrantDBEntities db = new EntrantDBEntities();
Entrant e = new Entrant()
{
FatherName = m.FatherName,
Lastname = m.LastName,
LocalAddress = m.LocalAddress,
Name = m.Name,
RegionID = m.RegionID,
PassportID = m.PassportID,
SchoolID = m.SchoolID,
SettlementID = m.SattlementID,
TaxID = m.TaxID,
};
db.Entrant.AddObject(e);
db.SaveChanges();
return RedirectToAction("Index");
}
}
View:
#model SSHS.Models.RecorderModels.CreateViewModel
#using SSHS.Models
#using (Html.BeginForm("Create", "Recorder", FormMethod.Post))
{
#foreach (Region item in ViewBag.Regions)
{
#Html.RadioButtonFor(m => m.RegionID, item.RegionID)
#Html.Label(item.RegionName) - #item.RegionID
}
...
...
}
The Create(CreateViewModel m) method gets data from all textboxes normaly, but RegionID always is 0.
How are you planning to fill radio button with int ? It have two states: checked and not. Could you tell us, what are you trying to do? Make radio group? Use bool for RadioButtonFor.
Added:
You need to write something like this: CheckboxList in MVC3.0 (in your example you will have radio buttons)
I have dropdowlist like this:
public class RegionLine
{
public Nullable<int> regionId { get; set; }
[Display(Name = "Województwo: ")]
public string regionName { get; set; }
}
and controller:
public PartialViewResult getPersonalData()
{
var d = rm.GetAllRegionsMapper();
ViewBag.Regions = new SelectList(rm.GetAllRegionsMapper().ToList(), "regionId", "regionName", "-- select item --");
var user = um.GetUserByLoginMapper(User.Identity.Name);
return PartialView("getPersonalData", user);
}
[HttpPost]
public PartialViewResult UpdatePersonalData(UserLine user)
{
var usr = um.GetUserByLoginMapper(User.Identity.Name);
ViewBag.Regions = new SelectList(rm.GetAllRegionsMapper().ToList(), "regionId", "regionName", "-- select item --");
if (ModelState.IsValid)
{
int status = uda.UpdateEmployeesPersonalData(user.UserId, user.PersonalData.Name, user.PersonalData.LastName,
user.Address.City, user.Address.Street, user.Address.Region.regionId, user.Address.PostCode,
user.PersonalData.KeyWord);
return PartialView("getLabelsPersonalData", user);
}
return PartialView("getPersonalData", usr);
}
the part of view with my dropdownlist:
<tr>
<td>#Html.LabelFor(a => a.Address.Region.regionName)</td>
<td>#Html.DropDownListFor(a => a.Address.Region.regionId, (SelectList)ViewBag.Regions)</td>
</tr>
and when i select some items, on httppost regionId is always null. Please help.
Its quite possible that rm.GetAllRegionsMapper().ToList() returns you a list with all regionId == null.
Also, why have you defined regionId as nullable? It always will be either key you selected from DropDownList or 0 if non was selected, no reason to have it as null ever.
You very much likely confusing between regionId that is key in the drop down list and the regionId that you trying to fetch after selection is made and posted back. Call the latter one selectedRegionId to avoid confusion.
Hope these few ideas will lead you to the right direction and help you localize your actual problem.
I've written a LINQ query shown below :
List<Actions> actions = resourceActions.Actions.Select(s => s.ActionName).ToList();
How do I give for selecting multiple columns here ? ie I want to add columns s.ActionId and s.IsActive. I'm unable to apply it.
Make a class to represent the data you want:
public class ResourceAction
{
public int Id {get;set;}
public string Name {get; set; }
}
Select a list of those instead:
List<ResourceAction> actions = resourceActions.Actions
.Select(s => new ResourceAction() { Id = s.Id, Name = s.ActionName}).ToList();
I believe this is what your looking for. However you need to change the output to an anonymous type.
var actions = resourceActions.Actions.Select(s => new { s.ActionName, s.ActionId, s.IsActive } ).ToList();
You can use a anonymous type for this, for example
var actions = resourceActions.Actions.Select(s =>
new { Id = s.Id, Name = s.ActionName, Active = s.IsActive).ToList();
but a better way would be to create a class like
public class ActionWithId
{
public int Id { get; set; }
public string Name { get; set; }
public bool Active { get; set; }
}
List<ActionWithId> actions = resourceActions.Actions.Select(s =>
new ActionWithId() { Id = s.Id, Name = s.ActionName, Active = s.IsActive }).ToList();
I been practicing with EF Code First, SQL Express, and ASP.Net MVC3.
When I run the website first the correct tables are generated by the FooInitializer and Student and Image are populated but for some reason the join table (StudentImages) is not being populated.
What could be the issue?
Tables: Student, Image, and StudentImages
public class Student
{
public int Id { get; set; }
public string Name { get; set; }
public virtual ICollection<Image> Images { get; set; }
}
public class Image
{
public int Id { get; set; }
public string Filename { get; set; }
public string Extension { get; set; }
public virtual ICollection<Student> Students { get; set; }
}
public class FooInitializer : DropCreateDatabaseIfModelChanges<DBContext>
{
protected override void Seed(DBContext context)
{
var students = new List<Student> {
new Student { Id = 1, Name = "John" },
new Student { Id = 2, Name = "Jane" }
};
students.ForEach(s => context.Students.Add(s));
context.SaveChanges();
var images = new List<Image> {
new Image { Id = 1, Filename = "IMG_4596.JPG", Extension = ".jpg" },
new Image { Id = 2, Filename = "IMG_4600.JPG", Extension = ".jpg" }
};
images.ForEach(i => context.Images.Add(i));
students[0].Images.Add(images[0]);
context.SaveChanges();
}
}
From what I can tell your Image class does not have a reference to the StudentID. Try adding:
public int StudentID { get; set; }
to the Image class maybe?
Also having an ICollection would mean that one image could have multiple students - is this correct? Maybe it should be a public virtual Student Student {...}
EDIT: Also I found this, with a many to many relationship (if thats what you need):
In your OnModelCreating() Method:
modelBuilder.Entity<Student>()
.HasMany(c => c.Images).WithMany(i => i.Students)
.Map(t => t.MapLeftKey("StudentId")
.MapRightKey("ImageID")
.ToTable("StudentImages"));
taken from this link that states:
A many-to-many relationship between the Instructor and Course
entities. The code specifies the table and column names for the join
table. Code First can configure the many-to-many relationship for you
without this code, but if you don't call it, you will get default
names such as InstructorInstructorID for the InstructorID column.
EDIT: Here is the code I used the other night, with my implementation of the code first MVC site:
var users = new List<User>
{
new User { UserID = new Guid(), Email = "me#me.com", LastOnline = DateTime.Now, Password = "pword", RegistrationDate = DateTime.Now, SecurityAnswer = "me", SecurityQuestion = "who?", Roles = new List<Role>() },
};
users.ForEach(s => context.Users.Add(s));
context.SaveChanges();
var roles = new List<Role>
{
new Role { RoleID = "Admin", Description = "Administration Users", Users = new List<User>() }
};
roles.ForEach(r => context.Roles.Add(r));
users[0].Roles.Add(roles[0]);
context.SaveChanges();
var userLicense = new List<UserLicense>
{
new UserLicense { AddDateTime = DateTime.Now, LicenseType = "Farmer", Manufacturer = "Motorola", Model = "Droid", PhoneIdentifier = "c0e4223a910f", UserID = users[0].UserID, User = new User() }
};
userLicense[0].User = users[0];
userLicense.ForEach(u => context.UserLicenses.Add(u));
context.SaveChanges();
userLicense[0].User = users[0];
context.SaveChanges();
Notice in each instantiated item, I am also instantiating a new referenced item within the parent object.
EDIT:
Ok try this:
var students = new List<Student> {
new Student { Id = 1, Name = "John", Images = new List<Image>() },
new Student { Id = 2, Name = "Jane", Images = new List<Image>() }
};
students.ForEach(s => context.Students.Add(s));
context.SaveChanges();
var images = new List<Image> {
new Image { Id = 1, Filename = "IMG_4596.JPG", Extension = ".jpg", Students = new List<Student>() },
new Image { Id = 2, Filename = "IMG_4600.JPG", Extension = ".jpg", Students = new List<Student>() }
};
images.ForEach(i => context.Images.Add(i));
students[0].Images.Add(images[0]);
students[1].Images.Add(images[1]);
context.SaveChanges();
Try adding this before saving changes for each student:
foreach (Image i in s1.Images)
context.ObjectStateManager.ChangeObjectState(i, System.Data.EntityState.Added);
Also try with System.Data.EntityState.Modified.
Hope this works...