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; }
}
Related
Hi I would want to have validations something of this sort
[RequiredCustom(ActionType=(int)Action.Update, ActionType=(int)Action.Delete)]
public string NotesID { get; set; }
[Required]
[RegularExpression("1|2|3|4")]
public int ActionType { get; set; }
I would want to validate this NotesID only when Updation and Deletion is taking place. I don't need any javascript code for unobtrusive and all. I just want server side validation.
Please don't suggest use of separate models I can't do that. Something similar solution will also do.
Let me know if this requires more clarification, Any help would be greatly appreciated.
If you are ok with placing the validation data annotations on the class itself, you could do something like the answer to this post (by Gary.S) suggests.
Here
In essense, just create a new custom validation attribute and since its an attribute at class level, you will have access to the object itself and hence access to other properties.
You custom attribute should look something like this (Assuming your class name is 'Notes')
public class RequiredCustom: ValidationAttribute
{
List<int> actions;
public RequiredCustom(int[] actions)
{
this.actions = new List<int>();
this.actions.AddRange(actions);
}
public override bool IsValid(object value)
{
bool isValid = true;
Notes testVal = value as Notes;
if(this.actions.Contains((int)testVal.Action))
{
if(string.IsNullOrWhiteSpace(testVal.NotesID))
{
isValid = false;
}
}
return isValid;
}
}
Then, add the validation attribute on the class and send the array of enums you want to test for. This way it will be dynamic enough to send other later. In this case, I am sending an ARRAY of Update and Delete enums since you have a special case for these two.
[RequiredCustom(new int[] {(int)Action.Update, (int)Action.Delete)}]
public class Notes
{
public string NotesID { get; set; }
[Required]
[RegularExpression("1|2|3|4")]
public int ActionType { get; set; }
}
Remember, this will work only if you set the attribute on the class, not on the NotesId property.
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 am creating a meta data class for a POCO object. I am adding the "CSVColumn" (from LINQToCSV) attribute to the meta data class. But when I run the program, it couldn't find its attributes.
So I tested it using reflection,
Type t = typeof(Case);
PropertyInfo pi = t.GetProperty("ProviderId");
//bool isReadOnly = ReadOnlyAttribute.IsDefined(pi,typeof( ReadOnlyAttribute);
var attributes = pi.GetCustomAttributes(typeof(Case),true);
It acutally return nothing by calling the "GetCustomAttributes".
What have I done wrong??
Below is the way I created metadata class.
One thing I don't understand is, it works perfectly well with MVC validations. Wondering how does that retrieve the custom attributes???
This is the entityframework POCO object
public partial class Case
{
public string ProviderName { get; set; }
public string ProviderId { get; set; }
}
Here I create a partial class of Case and metadata classes,
[MetadataType(typeof(CaseMetaData))]
public partial class Case
{
public class CaseMetaData
{
[CsvColumn(Name = "ProviderName", FieldIndex = 1)]
public string ProviderName { get; set; }
[CsvColumn(Name = "ProviderID", FieldIndex = 2)]
public string ProviderId { get; set; }
}
}
Please someone can help me, much appreciated.
Cheers
typeof(Case) isn't an attribute type.
You mean typeof(CsvColumnAttribute).
Also, standard Reflection isn't aware of metadata classes.
You need to use AssociatedMetadataTypeTypeDescriptionProvider.
A good example can be found here
I'm pulling my hair out on this one.
I am trying to implement a multi-step wizard, and i'm using the Html.Serialize html helper in MVC3 Futures. This works well, except one of the properties in my model is a SelectList. I don't want this property serialized (and it blows up when it tries anyways).
I can't use [NonSerialized] because that only works on fields, not properties. I've even tried some of the other normal ways such as [XmlIgnore] (which I didn't think would work anyways).
Can anyone suggest an attribute that will ignore a property in a model when using Html.Serialize?
EDIT:
The error I get when I try to serialize is a InvalidDataContractException. There is this message:
Type 'System.Web.Mvc.SelectList' cannot be serialized. Consider marking it with the DataContractAttribute attribute, and marking all of its members you want serialized with the DataMemberAttribute attribute. If the type is a collection, consider marking it with the CollectionDataContractAttribute. See the Microsoft .NET Framework documentation for other supported types.
However, if I do this then I have to mark all the members with [DataMember] just to exclude 1 property, which seems kind of stupid.
UPDATE:
A quick example of this is this bit of code (make sure to add reference to System.Runtime.Serialization.dll):
Test.cs
[Serializable]
public class Test
{
public int ID { get; set; }
[IgnoreDataMember]
public SelectList TestList { get; set; }
}
HomeController.cs
public ActionResult About()
{
return View(new Test() { ID = 0, TestList = new SelectList(new [] {""})});
}
Home/About.cshtml
#using Microsoft.Web.Mvc
#model MvcApplication3.Models.Test
#Html.Serialize("Test", Model)
This generates the InvalidDataContractException
public class MyViewModel
{
[IgnoreDataMember]
public SelectList Items { get; set; }
...
}
or simply:
public class MyViewModel
{
public IEnumerable<SelectListItem> Items { get; set; }
...
}
Since now I've used the excellent FluentValidation
library to validate my model classes. In web applications I use it in conjunction with the jquery.validate plugin to perform client side validation as well.
One drawback is that much of the validation logic is repeated on the client side and is no longer centralized at a single place.
For this reason I'm looking for an alternative. There are many examples out there showing the usage of data annotations to perform model validation. It looks very promising.
One thing I couldn't find out is how to validate a property that depends on another property value.
Let's take for example the following model:
public class Event
{
[Required]
public DateTime? StartDate { get; set; }
[Required]
public DateTime? EndDate { get; set; }
}
I would like to ensure that EndDate is greater than StartDate. I could write a custom
validation attribute extending ValidationAttribute in order to perform custom validation logic. Unfortunately I couldn't find a way to obtain the
model instance:
public class CustomValidationAttribute : ValidationAttribute
{
public override bool IsValid(object value)
{
// value represents the property value on which this attribute is applied
// but how to obtain the object instance to which this property belongs?
return true;
}
}
I found that the CustomValidationAttribute seems to do the job because it has this ValidationContext property that contains the object instance being validated. Unfortunately this attribute has been added only in .NET 4.0. So my question is: can I achieve the same functionality in .NET 3.5 SP1?
UPDATE:
It seems that FluentValidation already supports clientside validation and metadata in ASP.NET MVC 2.
Still it would be good to know though if data annotations could be used to validate dependent properties.
MVC2 comes with a sample "PropertiesMustMatchAttribute" that shows how to get DataAnnotations to work for you and it should work in both .NET 3.5 and .NET 4.0. That sample code looks like this:
[AttributeUsage(AttributeTargets.Class, AllowMultiple = true, Inherited = true)]
public sealed class PropertiesMustMatchAttribute : ValidationAttribute
{
private const string _defaultErrorMessage = "'{0}' and '{1}' do not match.";
private readonly object _typeId = new object();
public PropertiesMustMatchAttribute(string originalProperty, string confirmProperty)
: base(_defaultErrorMessage)
{
OriginalProperty = originalProperty;
ConfirmProperty = confirmProperty;
}
public string ConfirmProperty
{
get;
private set;
}
public string OriginalProperty
{
get;
private set;
}
public override object TypeId
{
get
{
return _typeId;
}
}
public override string FormatErrorMessage(string name)
{
return String.Format(CultureInfo.CurrentUICulture, ErrorMessageString,
OriginalProperty, ConfirmProperty);
}
public override bool IsValid(object value)
{
PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(value);
object originalValue = properties.Find(OriginalProperty, true /* ignoreCase */).GetValue(value);
object confirmValue = properties.Find(ConfirmProperty, true /* ignoreCase */).GetValue(value);
return Object.Equals(originalValue, confirmValue);
}
}
When you use that attribute, rather than put it on a property of your model class, you put it on the class itself:
[PropertiesMustMatch("NewPassword", "ConfirmPassword", ErrorMessage = "The new password and confirmation password do not match.")]
public class ChangePasswordModel
{
public string NewPassword { get; set; }
public string ConfirmPassword { get; set; }
}
When "IsValid" gets called on your custom attribute, the whole model instance is passed to it so you can get the dependent property values that way. You could easily follow this pattern to create a date comparison attribute, or even a more general comparison attribute.
Brad Wilson has a good example on his blog showing how to add the client-side portion of the validation as well, though I'm not sure if that example will work in both .NET 3.5 and .NET 4.0.
I had this very problem and recently open sourced my solution:
http://foolproof.codeplex.com/
Foolproof's solution to the example above would be:
public class Event
{
[Required]
public DateTime? StartDate { get; set; }
[Required]
[GreaterThan("StartDate")]
public DateTime? EndDate { get; set; }
}
Instead of the PropertiesMustMatch the CompareAttribute that can be used in MVC3. According to this link http://devtrends.co.uk/blog/the-complete-guide-to-validation-in-asp.net-mvc-3-part-1:
public class RegisterModel
{
// skipped
[Required]
[ValidatePasswordLength]
[DataType(DataType.Password)]
[Display(Name = "Password")]
public string Password { get; set; }
[DataType(DataType.Password)]
[Display(Name = "Confirm password")]
[Compare("Password", ErrorMessage = "The password and confirmation do not match.")]
public string ConfirmPassword { get; set; }
}
CompareAttribute is a new, very useful validator that is not actually
part of
System.ComponentModel.DataAnnotations,
but has been added to the
System.Web.Mvc DLL by the team. Whilst
not particularly well named (the only
comparison it makes is to check for
equality, so perhaps EqualTo would be
more obvious), it is easy to see from
the usage that this validator checks
that the value of one property equals
the value of another property. You can
see from the code, that the attribute
takes in a string property which is
the name of the other property that
you are comparing. The classic usage
of this type of validator is what we
are using it for here: password
confirmation.
It took a little while since your question was asked, but if you still like metadata (at least sometimes), below there is yet another alternative solution, which allows you provide various logical expressions to the attributes:
[Required]
public DateTime? StartDate { get; set; }
[Required]
[AssertThat("StartDate != null && EndDate > StartDate")]
public DateTime? EndDate { get; set; }
It works for server as well as for client side. More details can be found here.
Because the methods of the DataAnnotations of .NET 3.5 don't allow you to supply the actual object validated or a validation context, you will have to do a bit of trickery to accomplish this. I must admit I'm not familiar with ASP.NET MVC, so I can't say how to do this exactly in conjunction with MCV, but you can try using a thread-static value to pass the argument itself. Here is an example with something that might work.
First create some sort of 'object scope' that allows you to pass objects around without having to pass them through the call stack:
public sealed class ContextScope : IDisposable
{
[ThreadStatic]
private static object currentContext;
public ContextScope(object context)
{
currentContext = context;
}
public static object CurrentContext
{
get { return context; }
}
public void Dispose()
{
currentContext = null;
}
}
Next, create your validator to use the ContextScope:
public class CustomValidationAttribute : ValidationAttribute
{
public override bool IsValid(object value)
{
Event e = (Event)ObjectContext.CurrentContext;
// validate event here.
}
}
And last but not least, ensure that the object is past around through the ContextScope:
Event eventToValidate = [....];
using (var scope new ContextScope(eventToValidate))
{
DataAnnotations.Validator.Validate(eventToValidate);
}
Is this useful?