Is there a different way of setting the [AllowHtml] attribute on a property of a class that is being auto-generated by EntityFramework? I hate changing the autogenerated files because every time I make a change to the model, my changes get lost.
But there is no other obvious way for setting [AllowHtml] for a specific property other than by using the attribute. Is there a non-attribute way of doing it?
You can use the MetadataTypeAttribute to specify attributes for the generated code in an associated (buddy) class. So you put your attributes in a separate class which won't be effected with the code re-generation:
[MetadataType(typeof(YourEntityMetadata))]
public partial class YourEntityClass
{
}
public class YourEntityMetadata
{
[AllowHtml]
public string YourPropertyWithHtml { get; set; }
}
The property names in the Metadata class should match your entity property names.
Related
I am developing MVC application in which , I am trying to create the partial class of class generated by MVC application lets say Location class.
Now I want to create the partial class of Location class in new class file.
The below class code is auto genrated by MVC of Location code.
namespace CRM
{
public partial class Location
{
public int Id { get; set; }
public string Name { get; set; }
public string Remark { get; set; }
}
}
I have added new class file which contain the partial class of above file
namespace CRMEntities.Partial_Class
{
public interface ILocation
{
[StringLength(50, ErrorMessage = "Region can accept maximum 50 characters.")]
string Region { get; set; }
[Key]
int Id { get; set; }
[Required]
string Name { get; set; }
string Remark { get; set; }
}
public partial class Location : ILocation
{
}
}
Its giving the below error...
CRMEntities.Partial_Class.Location' does not implement interface member 'CRMEntities.Partial_Class.ILocation.Name
First, you don't need to do this, what I understand is you are trying to do validation right? Think about, the object generated by EF is not ViewModel, they are domain model. Data annotation should be in View Model, not domain model.
Most of cases, often mis-use is to use domain model as view model, but it is not correct much. Because sometime, view models need more than one domain model to provide data for your UI.
So for separation of concerns, you need to define your View Model different with domain model.
Example: you have Location class, you need to add LocationViewModel class and put data annotation in here.
You can map manually or use AutoMapper for mapping bettween View Model and Domain Model.
Another solution is you can use Fluent Validation, with this way, needless to have more partial class just for validation.
You don't show the definition of ILocation in your question, but the error says that the Location.Name property is declared differently than the ILocation.Name member.
Edit: Your two partial classes appear to be in two different namespaces, hence they are actually two entirely different classes, not two parts of the same class. That would explain the compiler error.
Having said that, I do agree with the other answer (+1!) that you should do your UI validation on a view model instead.
I figured out that property i want to be validated has to have [Required] attribute in C#
(am i right?)
If so -my model is linq generated class - how to add this attribute?
You can do it a couple of ways:
If it's possible, make the field non-nullable in the database. This will make the field required at the data layer.
Create a partial class that adds a property to your model class. Use this property instead of the database-generated property.
For example:
public partial class YourEntity
{
[Required]
public string YourNewProperty
{
get { return this.TheRealProperty; }
set { this.TheRealProperty = value; }
}
}
Hopefully this helps
well, you could always make a new class, as a part of a Data access layer, with the same attributes, just put [required] where you want.
I believe your LINQ classes are partials. With MVC, you can use the "MetatDataTypeAttribute"
Like so
[MetadataType(typeof(UserMetadataSource))]
public partial class User {
}
class UserMetadataSource {
[HiddenInput(DisplayValue = false)]
public int UserId { get; set; }
}
I am working on an mvc3 application and having some problems with getting validation to work as I want.
The application is using buddy classes for the models. (This is something I haven't used in the past and I am a little confused why they are used...anyway)
I want to add required fields to ensure data been submitted is correct. I have tried adding the required field to the buddy class.
When I submit the form no client-side validation takes place and the debugger steps into the entity frameworks generated code. Here is complains that the fields that contain null values are causing are invalid. If I step through all of those it finally gets to the controller where my if (ModelState.IsValid) is showing false.
I have client-side validation switched on.
Am I meant to be applying the data validation at the buddy class level or at the view model?
One other question is why use buddy classes? to me they seem to over complicate things.
Updated added an example of the buddy class
[MetadataType(typeof (CustomerMetaData))]
public partial class Customer
{
public string Priorty
{
get
{
var desc = (Priority) Priority;
return desc.ToString().Replace('_', ' ');
}
}
internal class CustomerMetaData
{
[Required]
[DisplayName("Priorty")]
public string Priorty { get; set; }
Buddy classes are metadata classes to put data annotation attributes when you are not in control of the original class i.e. can't edit it. Typical situation is when the class is generated by an ORM like Entity Framework.
//Can't edit this class
public partial class YourClass{
public string SomeField {get; set;}
}
//Add a partial class
[MetadataType(typeof(YourClassMetadata))]
public partial class YourClass{
}
//And a metadata class
public class YourClassMetadata
{
[Required(ErrorMessage = "Some Field is required")]
public string SomeField {get; set;}
}
are you sure that you have [MetadataType(typeof(YourClassMetadata))]?
More about buddy classes here and here
You would typically use a buddy class when it isn't possible to add meta data to an entity class such as when a model is automatically generated by an ORM tool. In this case any meta data you had applied would be lost.
Therefore, your original (automatically generated) class would be defined as a partial class:
public partial class Customer
{
public string Priority { get; set; }
}
And then you would generate your buddy classes to add the meta data.
[MetadataType(typeof(CustomerMetaData))]
public partial class Customer
{
}
internal class CustomerMetaData
{
[Required]
public string Priority { get; set; }
}
You would then pass the Customer class to the view where the Priority would be set.
In your case i'm not sure if you only have one partial class or two (as the other is not shown but please provide if there is). I'm interested to know how you obtain the priority information from the customer as i'm wondering if this is an issue with how you use ModelState.IsValid? The reason I ask is that no set accessor is declared on the Priority property so i'm wondering how this is set from the view in order to report that it is not valid?
You would also use a buddy class when it isn't possible to add meta data to an entity class such as when a model is automatically generated by an WCF Data Contract.
I'm working on an MVC3 application.
I created my POCO classes through the ADO.NET DbContext Generator and
I'm using partial classes to add validation on properties.
Now, when I try to serialize one of my entities I receive this error:
"Cannot serialize member .... of type
'System.Collections.Generic.ICollection`1[....."
I googled this error and I discovered that it's possible to add the tag
[XmlIgnore] to certain properties.
But the point is that I can't put this tag on the properties because they are
created everytime by the generator.
So how I can do this in a simpler way ?
The key is the MetadataTypeAttribute. You can add this to your partial class which implements the additional properties and your validation logic. Then create a meta data class with a property of the same name of your generated class, and apply the attribute you need.
[MetadataType(typeof(MyPOCOMetaData))]
public partial class MyPOCO
{
// your partial validation code and properties
}
public class MyPOCOMetaData
{
[XmlIgnore]
public string GenerateProperyName { get; set; }
}
Castle Validator uses attributes to specify validation rules. How can you hook these up with Subsonic's generated classes (or any classes where you can't define the attributes on)? Is there a way to programatically specify validation rules without using the attribute method?
I think the best way to do that is using MetadataType.
It's a DataAnnotations that let's your class have like a pair or something like that. I don't know how to explain it better so, let's for the samples:
You first need to add this directive to your code:
using System.ComponentModel.DataAnnotations;
Them you should create the partial class of you generated class with an attribute specifying that this class has an MetadataType:
[MetadataType(typeof(UserMetadata))]
public partial class User
{
}
Then you create your metadata class with your castle validation:
public class UserMetadata
{
[ValidateNonEmpty]
[ValidateLength(6, 24)]
public string Username { get; set; }
[ValidateNonEmpty]
[ValidateLength(6, 100)]
[ValidateEmail]
public string Email { get; set; }
[ValidateNonEmpty]
[ValidateLength(6, 24)]
public string Password { get; set; }
}
There are a few ways to do this - attributes is the lowest friction option, but obviously doesn't deal well with generated code or validation of multiple properties better expressed in code.
Take a look at the following link for some indications on how to do this blog post: Castle Validator Enhancements
If you have a look at the castle source code these are some good starting points:
IValidationContributor interface
DefaultValidationPerformer class