So I am trying to create my first block. The idea of this block is to get latest news from an api end point and then show it on different pages on the website.
What I have understood is this
Create a block type, something like this
public class NewsBlock : BlockData
{
[CultureSpecific]
[Display(
Name = "Heading",
Description = "Add a heading.",
GroupName = SystemTabNames.Content,
Order = 1)]
public virtual String Heading { get; set; }
}
Then I create a model for my Block
public class LatestNewsViewModel
{
public NewsBlock NewsBlock { get; private set; }
public IEnumerable<dynamic> LatestNews { get; set; }
public LatestNewsViewModel(NewsBlock latestNewsBlock, IEnumerable<dynamic> latestNews)
{
NewsBlock = latestNewsBlock;
LatestNews = latestNews;
}
}
Then I creata a block controller and in the index action I get data from my api and fill the block container data
Then I create a partial view and then from controller pass data into the view
Then from the dashboard I can add my block where ever I want on the site
Is this the way to do it? Or am I missing something?
That seem about correct. Please note there are many ways and opinions on how to get your data from the content model through the controller to the actual view. The example below is just the most simple scenario I can come up with.
public class NewsBlock : BlockData
{
[CultureSpecific]
[Display(
Name = "Heading",
Description = "Add a heading.",
GroupName = SystemTabNames.Content,
Order = 1)]
public virtual String Heading { get; set; }
}
The controller
public class NewsBlockController : BlockController<NewsBlock>
{
// GET: NewsBlock
public override ActionResult Index(NewsBlock currentBlock)
{
// apistuff
ApiModelWhatever returnFromApi = "whatever";
var model = new LatestNewsViewModel(currentBlock, returnFromApi);
return PartialView(model);
}
}
ViewModel
public class LatestNewsViewModel
{
public string Heading { get; private set; }
public ApiModelWhatever ReturnFromApi { get; private set; }
public LatestNewsViewModel(NewsBlock latestNewsBlock, ApiModelWhatever returnFromApi)
{
Heading = latestNewsBlock.Heading;
ReturnFromApi = returnFromApi;
}
}
View
#model LatestNewsViewModel
<h2>#Html.PropertyFor(model => model.Heading)</h2>
Related
I'm working on my first WPF MVVM application. I created a database and wrote queries to fetch album names and song names. Now I want to fill a list in my View with the album names and a second list with corresponding songs. I'm new to c# and WPF. I'd like to know how a view model would like for my controller would look like.
My controller:
public class BandManagerController
{
private bandkramEntities _context;
public BandManagerController()
{
_context = new bandkramEntities();
}
public List<AlbumData> GetAlbumList()
{
return _context.albums
.Select(a => new AlbumData
{
AlbumID = a.AlbumID,
AlbumName = a.AlbumName,
})
.ToList();
}
public List<SongData> GetSongList(int albumID)
{
return _context.songs
.Where(s => s.AlbumID == albumID)
.Select(s => new SongData
{
SongID = s.SongID,
SongName = s.SongName
})
.ToList();
}
}
I created a helper class with the NotifyOfPropertyChange class and a song and album data class:
AlbumData.cs
public class AlbumData
{
public string AlbumName { get; set; }
public int AlbumID { get; set; }
}
SongData.cs
public class SongData
{
public string SongName { get; set; }
public int SongID { get; set; }
}
For a better overview I want to split my Viewmodel into 4 main parts.
SongViewModel.cs
public class SongViewModel : NotifyOfPropertyChange
{
public SongViewModel()
{
}
public string SongName { get; set; }
public int SongID { get; set; }
}
AlbumViewModel.cs
public class AlbumViewModel : NotifyOfPropertyChange
{
public AlbumViewModel()
{
}
public string AlbumName { get; set; }
public int AlbumID { get; set; }
}
SongListViewModel.cs
AlbumListViewModel.cs
I would like to know how 3. and 4. would have to look like to fill the album list with the album names and show corresponding songs in a second list.
With MVVM you would lose the controller and just have a ViewModel. There you would have your lists as such(including a notify property changed)
private ObservableCollection<SongData> _songList;
public ObservableCollection<SongData> SongList
{
get { return _songList; }
set { SetProperty(ref _songList, value, () => SongList); }
}
Then you would load this list at some point
public void LoadSongData(int albumID)
{
Using(YourContext _context = new YourContext)
{
SongList = new ObservableCollection(_context.songs
.Where(s => s.AlbumID == albumID)
.Select(s => new SongData
{
SongID = s.SongID,
SongName = s.SongName
})
.ToList());
}
}
I got the error Invalid object name 'dbo.Staffs'. but I'm not sure why. I actually deleted and recreated my database with EF because previously I had other errors. But I'm quite sure I recreated it correctly because I've done it in the same way for other programs and it works fine.
.edmx database diagram
Controller
private StaffPortalDBEntities1 db = new StaffPortalDBEntities1();
SqlConnection cnn = new SqlConnection(ConfigurationManager.ConnectionStrings["StaffPortalDBConnectionString"].ConnectionString);
[Authorize]
public ActionResult Index()
{
var userEmail = User.Identity.Name;
var model = db.Staffs.Where(i => i.Email == userEmail).Include("Histories").Include("CurrentApplications").FirstOrDefault();
return View(model);
}
I got the error is for the line var model = db.Staffs.Where(i => i.Email == userEmail).Include("Histories").Include("CurrentApplications").FirstOrDefault();
Generated Staff class
public partial class Staff
{
public Staff()
{
this.Histories = new HashSet<History>();
this.CurrentApplications = new HashSet<CurrentApplication>();
}
public int StaffID { get; set; }
public string Name { get; set; }
public string Email { get; set; }
public Nullable<decimal> AllocatedLeave { get; set; }
public Nullable<int> BalanceLeave { get; set; }
public virtual ICollection<History> Histories { get; set; }
public virtual ICollection<CurrentApplication> CurrentApplications { get; set; }
}
Try this:
var model = db.Staffs.Where(i => i.Email == userEmail).Include(x=>x.Histories).Include(x=>x.CurrentApplications).FirstOrDefault();
I'm having some doubts, maybe newbie doubts but I just got into ASP.NET MVC 4
Basically I would like to know the correct way of grabbing details of an Object inside a model.
In this case Image inside Contractor.
Model:
public class Contractor {
[Key]
public int ContractorID { get; set; }
[Required]
public string Name { get; set; }
[Required]
public string Address { get; set; }
public Image Avatar { get; set; }
}
public class Image {
[Key]
public int ImageID { get; set; }
[Required]
public string File_name { get; set; }
[Required]
public byte[] File_data { get; set; }
}
public class DATACRUD : DbContext {
public DbSet<Contractor> Companies { get; set; }
public DbSet<Image> Images { get; set; }
}
Controller:
private DATACRUD db = new DATACRUD();
public ActionResult GetContractorAvatar(int id)
{
Contractor contractor = db.Contractors.Find(id);
if (contractor == null)
{
return HttpNotFound();
}
Image avatar = contractor.Avatar;
Problem 1)
avatar == null, but is not suppose to be because when I created the object Contractor, I added the image sucessfully (I checked in the DB and it is there)
The solution I'm seeing is instead of having Image property in Contractor.cs model, I would just put a string property with the image key.
Problem 2)
Even If could grab the image key like I said in the previous problem, when I pass my mouse in Debug mode over
private DATACRUD db = new DATACRUD ();
db.Images is also empty...
return File(avatar.File_data, "image");
}
Because you haven't defined your Image navigation property as virtual, you will have to eager load the Image when loading a Contractor:
db.Contractors.Include("Avatar").SingleOrDefault(c => c.ContractorID == id);
OR
// using System.Data.Entity;
db.Contractors.Include(c => c.Avatar).SingleOrDefault(c => c.ContractorID == id);
In order to create a more elegant solution I'm curios to know your suggestion about a solution to persist a collection.
I've a collection stored on DB.
This collection go to a webpage in a viewmodel.
When the go back from the webpage to the controller I need to persist the modified collection to the same DB.
The simple solution is to delete the stored collection and recreate all rows.
I need a more elegant solution to mix the collections and delete not present record, update similar records ad insert new rows.
this is my Models and ViewModels.
public class CustomerModel
{
public virtual string Id { get; set; }
public virtual string Name { get; set; }
public virtual IList<PreferredAirportModel> PreferedAirports { get; set; }
}
public class AirportModel
{
public virtual string Id { get; set; }
public virtual string AirportName { get; set; }
}
public class PreferredAirportModel
{
public virtual AirportModel Airport { get; set; }
public virtual int CheckInMinutes { get; set; }
}
// ViewModels
public class CustomerViewModel
{
[Required]
public virtual string Id { get; set; }
public virtual string Name { get; set; }
public virtual IList<PreferredAirporViewtModel> PreferedAirports { get; set; }
}
public class PreferredAirporViewtModel
{
[Required]
public virtual string AirportId { get; set; }
[Required]
public virtual int CheckInMinutes { get; set; }
}
And this is the controller with not elegant solution.
public class CustomerController
{
public ActionResult Save(string id, CustomerViewModel viewModel)
{
var session = SessionFactory.CurrentSession;
var customer = session.Query<CustomerModel>().SingleOrDefault(el => el.Id == id);
customer.Name = viewModel.Name;
// How can I Merge collections handling delete, update and inserts ?
var modifiedPreferedAirports = new List<PreferredAirportModel>();
var modifiedPreferedAirportsVm = new List<PreferredAirporViewtModel>();
// Update every common Airport
foreach (var airport in viewModel.PreferedAirports)
{
foreach (var custPa in customer.PreferedAirports)
{
if (custPa.Airport.Id == airport.AirportId)
{
modifiedPreferedAirports.Add(custPa);
modifiedPreferedAirportsVm.Add(airport);
custPa.CheckInMinutes = airport.CheckInMinutes;
}
}
}
// Remove common airports from ViewModel
modifiedPreferedAirportsVm.ForEach(el => viewModel.PreferedAirports.Remove(el));
// Remove deleted airports from model
var toDelete = customer.PreferedAirports.Except(modifiedPreferedAirports);
toDelete.ForEach(el => customer.PreferedAirports.Remove(el));
// Add new Airports
var toAdd = viewModel.PreferedAirports.Select(el => new PreferredAirportModel
{
Airport =
session.Query<AirportModel>().
SingleOrDefault(a => a.Id == el.AirportId),
CheckInMinutes = el.CheckInMinutes
});
toAdd.ForEach(el => customer.PreferedAirports.Add(el));
session.Save(customer);
return View();
}
}
My environment is ASP.NET MVC 4, nHibernate, Automapper, SQL Server.
Well, if "elegant" is just "don't clear and recreate all" (untested) :
var airports = customer.PreferedAirports;
var viewModelAirports = viewModel.PreferredAirports;
foreach (var airport in airports) {
//modify common airports
var viewModelAirport = viewModelAirports.FirstOrDefault(m => m.AirportId == airport.AirportId);
if (viewModelAirport != null) {
airport.X = viewModelAirport.X;
airport.Z = viewModelAirport.Z;
//remove commonAirports from List
viewModelAirports.Remove(viewModelAirport);
continue;
}
//delete airports not present in ViewModel
customer.PreferedAirports.Remove(airport);
}
//add new airports
foreach (var viewModelAirport in viewModelAirports) {
customer.PreferedAirports.Add(new PreferredAirportModel {
Airport = session.Query<AirportModel>().SingleOrDefault(a => a.Id == el.AirportId),
CheckInMinutes = el.CheckInMinutes
});
}
session.Save(customer);
I'm just learning ASP.NET MVC 3, And recently I tried a lot of times to pass arrays/lists/ICollections etc. but couldn't. everytime the list was empty.
For example, the current project:
Model:
public class Video
{
public int VideoID { get; set; }
public string Name { get; set; }
public ICollection<string> Tags { get; set; }
}
Initializer - Seed:
protected override void Seed(DatabaseContext context)
{
var videos = new List<Video>
{
new Video {
Name = "Video01",
Tags = new List<string> { "tag1", "tag2" },
};
videos.ForEach(s => context.Videos.Add(s));
context.SaveChanges();
base.Seed(context);
}
In the view: I do get the Name property, but the Tags are completely empty.
In the debug I get Tags - Count: 0.
This is not the first time it happens to me, to be honest it happens every single time when I try to pass those kind of stuff. a bit of info about the project:
ASP.NET MVC 3, Entity-Framework:Code First, SqlServerCe.4.0.
Crean an entity Tag
public class Video
{
public int VideoID { get; set; }
public string Name { get; set; }
public ICollection<Tag> Tags { get; set; }
}
public class Tag
{
public int TagId { get; set; }
public int VideoId { get; set; }
public string TagText { get; set; }
}
or store tags to one field separated with comma /semicolon or whatever fits for your solution
By default Entity Framework doesn't load associations of an entity, you need to specify it explicitly:
var videos = context.Videos.Include("Tags");