I'll let the code do the talking here, I have something like this:
class Problem
{
public string Title { get; set; }
public string Description { get; set; }
public virtual IList<Symptom> Symptoms { get; set; }
}
class Symptom
{
public string Comments { get; set; }
public virtual Category Category { get; set; }
}
class Category
{
public string Name { get; set; }
}
I have a modal that allows users to add a list of symptoms on my view. Each symptom being added produces an INPUT that looks like this (where N is the index):
<input type="text" name="Symptom[N].Name" value="#Model.Symptom[N].Name">
<input type="text" name="Symptom[N].Category" value="#Model.Symptom[N].Category">
Once I POST the data to my controller, the model contains a valid list of Symptom (if I add 3, my Product.Symptom list has 3 entities) and the [Comments] of each symptom has persisted, but the [Category] property of each is NULL. What am I doing wrong here? I've tried numerous things but I still end up with NULL as the [Category] for each.
I'm using Entity Framework 4.1 Code First with Fluent API developing in MVC 3 using Razor syntax.
Try this:
<input type="text"
name="Symptom[N].Category.Name"
value="#Model.Symptom[N].Category.Name">
What I think is happening is that it's trying to bind a string to a Category which is invalid. If you want to map the text to the Name property on the Category class, you will need to specify it one level deeper.
Related
I'm using entity framework and MVC (both CORE if that matters) to make a site. Using the model and tying it directly to the view is fine all the CRUD actions work, everything is lovely.
I wanted to use a couple of pages to access the model so the site looked better, so split the controls out onto separate views and added a corresponding viewmodel for each, so my project looks like this
-Model
--CustomerModel
-ViewModel
--CustomerNameVM
--CustomerAddressVM
-View
--CustomerNameView
--CustomerAddressView
The CustomerModel has a number of properties
Forename
Surname
Address
Postcode
with Forename and Surname in the CustomerNameVM and Address and Postcode in CustomerAddressVM. Surname is defined as [Required] in the model but not in CustomerNameVM which I believe is the correct way to do it.
I'm struggling to get the model loaded into the viewmodel and then trying to save it when I'm editing the address details in CustomerAddressView because it errors when I try and save as the viewmodel doesn't contain Surname (from the model), so it's null and therefore the [Required] criteria isn't being met.
I've tried a few methods of trying to get past this like :-
Jeffrey Palermo's Onion Architecture
Repositories
domain models
amongst others which all end up with the same problem, I can't save the Address as the Surname is null.
How do I ignore validation criteria for the properties of the model that aren't being referenced in the viewmodel?
Or how do I load and reference only those properties of the model that are present in viewmodel?
Edit
For those who keep asking for code, which codeset? I've tried 30 of them now, none of which do the job. Which one of these do you want? I'm trying to get a general idea of how this is supposed to work as none of the methods, documentation and associated examples function.
Here's a starter for 10, it's unlike the other 29 codesets but it's code and probably the shortest.
The controller
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Step2Address(int? id, [Bind("CustomerID,txtAddress,txtPostcode")] VMAddress VMAddress) {
if (ModelState.IsValid) {
//the saving code
}
return View(VMAddress);
}
the model
public class clsCustomer {
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int CustomerID { get; set; }
public string Forename { get; set; }
[Required]
public string Surname { get; set; }
public string Address { get; set; }
public string Postcode { get; set; }
the viewmodel
public class VMAddress {
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int CustomerID { get; set; }
public string Address { get; set; }
public string Postcode { get; set; }
}
the view
#model theProject.Models.VMStep2Contact
<form asp-action="Step2Address">
<input type="hidden" asp-for="ComplaintID" />
<input asp-for="txtAddress"/>
<input asp-for="txtPostcode"/>
<input type="submit" value="Save" />
the context
public class ContextCustomer : DbContext {
public ContextCustomer(DbContextOptions<ContextCustomer> options) : base(options) {
}
public DbSet<clsCustomer> Customer{ get; set; }
}
Clicking "Save" on the webpage calls the controller straight away, which hits the first line if (ModelState.IsValid) and as the Surname isn't set and is [Required] the ModelState is not valid so no save is attempted.
I don't actually understand what the problem is, and without code, it's impossible to say what you might be doing wrong. Generally speaking, you shouldn't have any issues since you're using view models.
A view model is, of course, not saved directly to the database, so it has to be mapped over to an actual entity class that you will be saving. In the case of an edit, you should retrieve all relevant entities from the database, map any posted values onto the appropriate properties on those entities, and then save those entities back to the database. If you're doing this, presumably, the customer model should already contain the Surname and other required properties, and you'd only be modifying/setting the address properties.
If you're doing a create, then, simply you can't just take address information. You need the name as well, so for this, you'd need to pass a view model that contains at least all required fields, such that you have all the information you need to actually save the entity.
If you're trying to do a multi-step form, where you collect all the information over multiple posts, then you simply must persist the posted data somewhere other than the database until you have enough of it to actually save an entity to the database. This is usually accomplished via Session/TempData.
have very simple relationship between two entities and I am trying to expose them with asp.net webapi odata controllers but it seems that something is wrong with $metadata.
When I run jaydatasvcutil.exe on the $metadata I get warning: inverseProperty other side missing.
When I use breezejs loadNavigationProperty I get similar error.
I have the problem even with official example.
http://www.asp.net/web-api/overview/odata-support-in-aspnet-web-api/working-with-entity-relations
You can observe the $metadata here http://sdrv.ms/Z5Klfw
Please help.
When we are generating navigation properties we don't reuse the relationships.
For example, lets say you have simple model,
public class Product
{
public int Id { get; set; }
public Supplier Supplier { get; set; }
}
public class Supplier
{
public int Id { get; set; }
public Product[] Products { get; set; }
}
The $metadata for the navigation properties that we generate looks like this,
<NavigationProperty Name="Supplier" Relationship="ProductsService.Models.ProductsService_Models_Product_Supplier_ProductsService_Models_Supplier_SupplierPartner" ToRole="Supplier" FromRole="SupplierPartner" />
<NavigationProperty Name="Products" Relationship="ProductsService.Models.ProductsService_Models_Supplier_Products_ProductsService_Models_Product_ProductsPartner" ToRole="Products" FromRole="ProductsPartner" />
Notice that we are generating two relationships instead of one. The reason we do that is that it is a hard problem to figure out if two navigation properties represent the same relationship. Take the instance of Product and Manufacturer.
public class Manufacturer
{
public int Id { get; set; }
public Product[] RawMaterials { get; set; }
public Product[] Produces { get; set; }
}
public class Product
{
public int Id { get; set; }
public Manufacturer[] Producers { get; set; }
public Manufacturer[] Consumers { get; set; }
}
It is not trivial to figure out that Maufacturer.RawMaterials and Product.Consumers should share the same relationship and Manufaturer.Produces and Product.Producers should share the same relationship. We chose not to do it because the clients that we know of don't make much out of this information.
All this happens because OData uses the same EDM model as the entityframework. Entityframework requires this information as it maps these relationships to association sets which would become tables in the database.
Another reason we chose not to do it is that this could be going away in OData V4. Check out the working draft here (page 23 and page 57 would be of interest). In short, navigation properties in $metadata in OData V4 would look more like this,
<NavigationProperty Name="Category" Type="Self.Category" Nullable="false" Partner="Products" />
Notice that there is no relationship and there would be no association sets.
My viewmodel inherits from a class that inherits from an abstract class that has a property with a [Required] attribute, but the rule doesn't appear in the DOM and unobtrusive validation doesn't catch the error.
The display attribute goes through fine, but the validation DOM attributes are not added to the textarea
my view has this:
#model FormPersonView
....
#Html.TextAreaFor(m => m.Description)
#Html.ValidationMessageFor(m => m.Description)
my code has this:
public class FormPersonView : Person
{
//View related stuff
.....
.....
}
public class Person : BasePerson
{
//Person related stuff - validation for these work!
[Required]
public string FirstName { get; set; }
[Required]
public string LastName { get; set; }
}
public abstract class BasePerson
{
//Base person stuff - validation for this doesn't work!
public string Id { get; set; }
[Required]
[Display("Short description of the person")]
public string Description { get; set; }
}
Why does it work with one level of inheritance but not two? It does work on the server side.
Had exactly this problem. While defining the view, the model comes as a type you defined #model FormPersonView. Data annotations will only work on that specific type, even if you have derived properties from children, their data annotations won't be engaged.
The solution that I came up with in my project was to define editor templates for types I needed data annotations to work properly and then calling #EditorFor on those models. Then and only then were data annotations operating as expected.
Hope this help you.
I have 2 models, employee and person:
public class Employee
{
[Key]
public int Id { get; set; }
public int? PersonId { get; set; }
[ForeignKey("PersonId")]
public virtual Person Person { get; set; }
}
public class Person
{
public IList<PhoneNumber> PhoneNumbers { get; set; }
public int Id { get; set; }
public string FName { get; set; }
public string LName { get; set; }
public Person()
{
PhoneNumbers = new List<PhoneNumber>
{
new PhoneNumber()
};
}
}
Editor Template for Phone:
#Html.TextBoxFor(x => x.Number)
#Html.DropDownListFor(m => m, new SelectList(Enum.GetNames(typeof (WebMVC.Core.Common.PhoneType))))
To reduce clutter, I removed the other (non-pertinent) properties.
The difficulty I am having is while in the Employee Create(), I can bind the person FName & LName, I cannot bind the PhoneNumbers collection.
I know about the 2008 Haack blog but I do not think it mirrors this situation.
Does anyone know a solution to bind the person phone numbers collection in the employee's Create()?
I'm not exactly sure if PhoneNumber is a custom class that you created, or one that is built into the framework. But if you're having problems with MVC3 mapping posted data to the Employee class like you specified, you might want to look at creating a custom binding. Keep in mind that if your editor template code is incorrect this wont really matter, so I would take a look at that using fiddler first.
Here are a few good sites to get you started, I found them all on SO at one point.
http://odetocode.com/blogs/scott/archive/2009/04/27/6-tips-for-asp-net-mvc-model-binding.aspx
http://odetocode.com/blogs/scott/archive/2009/05/05/iterating-on-an-asp-net-mvc-model-binder.aspx
http://www.singingeels.com/Articles/Model_Binders_in_ASPNET_MVC.aspx
Creating a custom binder gives you complete control over the way that MVC parses your posted model data and populates the object. There are 2 main functions that most people override, CreateModel and BindModel. BindModel is the function you will most likely want to override if this is the way you would like to go.
I don't know what the html from the editor template looks like, but to bind to a collection of custom types it should look something like this:
<input name="[0].Number">
<input name="[0].PhoneType">
<input name="[1].Number">
<input name="[1].PhoneType">
<input name="[2].Number">
<input name="[2].PhoneType">
For an ongoing project i have (amongst other classes) the following:
public class Page
{
[Key]
public int PageId { get; set; }
public string Name { get; set; } //eg. "AboutUs", "Location"
[Column(TypeName = "ntext")] //force Entity Framework to create a ntext column
public string Title { get; set; }
public string Subtitle { get; set; }
public string Content { get; set; }
//navigational properties
public virtual ObservableCollection<Image> Images{ get; set; } //one Page has many Images
public Page()
{
Images= new ObservableCollection<Image>();
}
}
I'm using Entity Framework code first approach in this ASP MVC 3 project (using Razor) and do not have any problem inserting and updating objects of this type.
BUT: how can i have a master detail view in which the detail part is composed by images only (see class definition).
So how is it possible to add an image, if the user doesn't want it to have it deleted and of course how to show all the images in a list?
Any hint is deeply appreciated!
Look at this post: Display image from database in asp mvc
If you are trying to render from the database, create a method in your controller to get the image and use that as your image source like in the example above. The only difference is yours will be contained in a
<ul>
#foreach(var image in Model.Images) {
<li><img src="#Url.Action("Show", "Image", new {id = image.Id})" /></li>
}
</ul>
Then your model would contain the Id's of the images, and it would be the job of the action method to retrieve the image.