Validation Attributes MVC 2 - checking one of two values - validation

Could someone help me with this issue. I'm trying to figure out how to check two values on a form, one of the two items has to be filled in. How do I do a check to ensure one or both of the items have been entered?
I'm using viewmodels in ASP.NET MVC 2.
Here's a little snip of code:
The view:
Email: <%=Html.TextBoxFor(x => x.Email)%>
Telephone: <%=Html.TextBoxFor(x => x.TelephoneNumber)%>
The viewmodel:
[Email(ErrorMessage = "Please Enter a Valid Email Address")]
public string Email { get; set; }
[DisplayName("Telephone Number")]
public string TelephoneNumber { get; set; }
I want either of these details to be provided.
Thanks for any pointers.

You can probably do this in much the same way as the PropertiesMustMatch attribute that comes as part of the File->New->ASP.NET MVC 2 Web Application.
[AttributeUsage(AttributeTargets.Class, AllowMultiple = true, Inherited = true)]
public sealed class EitherOrAttribute : ValidationAttribute
{
private const string _defaultErrorMessage = "Either '{0}' or '{1}' must have a value.";
private readonly object _typeId = new object();
public EitherOrAttribute(string primaryProperty, string secondaryProperty)
: base(_defaultErrorMessage)
{
PrimaryProperty = primaryProperty;
SecondaryProperty = secondaryProperty;
}
public string PrimaryProperty { get; private set; }
public string SecondaryProperty { get; private set; }
public override object TypeId
{
get
{
return _typeId;
}
}
public override string FormatErrorMessage(string name)
{
return String.Format(CultureInfo.CurrentUICulture, ErrorMessageString,
PrimaryProperty, SecondaryProperty);
}
public override bool IsValid(object value)
{
PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(value);
object primaryValue = properties.Find(PrimaryProperty, true /* ignoreCase */).GetValue(value);
object secondaryValue = properties.Find(SecondaryProperty, true /* ignoreCase */).GetValue(value);
return primaryValue != null || secondaryValue != null;
}
}
The key part of this function is the IsValid function that determines if one of the two parameters has a value.
Unlike normal Property-based attributes, this is applied to the class level and can be used like so:
[EitherOr("Email", "TelephoneNumber")]
public class ExampleViewModel
{
[Email(ErrorMessage = "Please Enter a Valid Email Address")]
public string Email { get; set; }
[DisplayName("Telephone Number")]
public string TelephoneNumber { get; set; }
}
You should be able to add as many as these as you need per form, but if you want to force them to enter a value into one of more than two boxes (Email, Telephone or Fax for example), then you would probably be best changing the input to be more an array of values and parse it that way.

Related

FluentValidation Set Valid Result to a Custom Property

I am validating the content for file import and I have an IsValid property for each line.
public class Header
{
public int LineNumber { get; set; }
public string Property1 { get; set; }
public string Property2 { get; set; }
public bool IsValid { get; set; }
}
public class Detail
{
public int LineNumber { get; set; }
public string Property1 { get; set; }
public string Property2 { get; set; }
public string Property3 { get; set; }
public bool IsValid { get; set; }
}
public class Trailer
{
public int LineNumber { get; set; }
public string Property1 { get; set; }
public bool IsValid { get; set; }
}
public class ImportFile
{
public Header Header { get; set; }
public List<Detail> Details { get; set; }
public Trailer Trailer { get; set; }
}
and my validators look somewhat like:
public class DetailValidator : AbstractValidator<Detail>
{
public DetailValidator()
{
RuleFor(d => d.Property1)
.Cascade(CascadeMode.Stop)
.NotEmpty()
.WithState(d => d.LineNumber)
.Length(3)
.WithState(d => d.LineNumber);
RuleFor(d => d.Property2)
.Cascade(CascadeMode.Stop)
.NotEmpty()
.WithState(d => d.LineNumber)
.MaximumLength(50)
.WithState(d => d.LineNumber);
...
}
}
public class ImportFileValidator : AbstractValidator<ImportFile>
{
public ImportFileValidator()
{
RuleFor(f => f.Header)
.SetValidator(new HeaderValidator());
RuleForEach(f => f.Details)
.SetValidator(new DetailsValidator());
...
}
}
After I call the validation, I wanted to set the IsValid property of each line of the file (be it header, detail or trailer) base from the result of the validation.
What is possible for now is, since I am using WithState to store the LineNumber, I can match the ValidationResult against the ImportFile instance to set each line's validity like below:
ImportFile file = // parsed file content
var result = new ImportFileValidator().Validate(file);
foreach (var detail in file.Details)
{
var error = result.Errors.FirstOrDefault(e =>
Convert.ToInt32(e.CustomState) == detail.LineNumber);
detail.IsValid = error == null;
}
And I have to check for the header and trailer as well.
Is there a way I can do this inside the validators? I am trying to explore the FluentValidation's documentation, but I can't seem to find what I needed there.
As I was exploring the available methods in FluentValidation, I saw OnFailure and OnAnyFailure methods. This methods might be a good help to what I needed to do, but the problem is they're obsolete as of 10.3.0 and will be removed on version 11. They're suggesting to use a custom validator instead.
The Header, Detail and Trailer Abstract Validators remain as is.
I created custom validator extensions for those 3.
Each extension methods creates an instance of the corresponding validator and executes it. I can make them generic for header, detail and trailer since they will do the same thing, set IsValid property to the validation result.
public static IRuleBuilderOptionsConditions<ImportFile, T> IsHeaderValid<T>(this IRuleBuilder<ImportFile, T> ruleBuilder)
where T : Header
{
return builder.Custom((header, context) =>
{
// Create the Header Abstract Validator Instance
var validator = new HeaderValidator();
var result = validator.Validate(Header);
header.IsValid = result.IsValid;
// Pass the errors to the context
result.Errors.ForEach(context.AddFailure);
}
}
I had to change the ImportFileValidator to call the custom validators, instead of using setvalidator.
The ImportFileValidator looks like this:
public class ImportFileValidator : AbstractValidator<ImportFile>
{
public ImportFileValidator()
{
RuleFor(f => f.Header)
.IsHeaderValid();
RuleForEach(f => f.Details)
.IsDetailValid();
...
}
}
This is pretty much how I was able to set the IsValid property without having to do the matching I initially did in the question.

Validating complex class in MVC

Consider the following code:
public class AccountNumber
{
[AccountNumber] //This validator confirms the format of the account number
public string Value {get; set;}
public int Format { get; set;}
public string ToString()
{
return Value + " is format " + Format;
}
}
public class MyViewModel
{
public MyViewModel()
{
SourceAccount = new AccountNumber();
DestinationAccount= new AccountNumber();
}
[Required]
AccountNumber SourceAccount {get; set;}
AccountNumber DestinationAccount {get; set;}
}
And then, in my View:
#Html.EditorFor(model => model.SourceAccount.Value)
#Html.EditorFor(model => model.DestinationAccount.Value)
Basically, I want to say that the user must enter a Source Account, and that they optionally enter a Destination Account. However, if they do enter a Destination Account it must conform to a certain format.
The problem with the code above is that the required validator on the SourceAccount will always return valid, as SourceAccount is never null. What would be a good approach for implementing what I am trying to achieve?
Please note that in real-life the setter for Value is more complex than shown, as it reformats the account number in a canonical format.
Edit Please note that we have to use inbuilt MVC validation, as that is what the rest of the project is currently using.
See Extending the Model Binder for Enhanced Validation.
This is fully compatible with built-in MVC validation.
You can - of course - customize this solution by using your own interface for validation.
A simple approach could be to add simple string properties for the SourceAccount and DestinationAccount numbers as follows:
public class MyViewModel
{
public MyViewModel()
{
}
[Required]
[AccountNumber]
public string SourceAccountNumber { get; set; }
[AccountNumber]
public string DestinationAccountNumber { get; set; }
public AccountNumber SourceAccount
{
get
{
return new AccountNumber
{
Value = SourceAccountNumber,
Format = 0 // Set Format appropriately
};
}
}
public AccountNumber DestinationAccount
{
get
{
return new AccountNumber
{
Value = DestinationAccountNumber,
Format = 0 // Set Format appropriately
};
}
}
}
Maybe you'd like to try FluentValidation, it's a model validation alternative to data annotation attributes, which allows you to add more complex model validation logic.
The code is still pretty concise and straightforward:
[Validator(typeof(PersonValidator))]
public class Person
{
public int Id { get; set; }
public string Name { get; set; }
public string Email { get; set; }
public int Age { get; set; }
}
public class PersonValidator : AbstractValidator<Person>
{
public PersonValidator()
{
RuleFor(x => x.Id).NotNull();
RuleFor(x => x.Name).Length(0, 10);
RuleFor(x => x.Email).EmailAddress();
RuleFor(x => x.Age).InclusiveBetween(18, 60);
}
}

Asp.Net Mvc 2 Custom Validation Issue

My question is regarding MVC 2 custom validation. I'm stuck on a particular issue and I'm unsure how to get around it. I'm fairly sure it's more figuring out how to do it logically and then implementing it in code.
So what we have is a metadata class for a product. Each product has a product product ID which is the PK, and obviously unique. Each product also has a product code which is also unique. Customers enter the product code however, but the nature of the code ensures that only one code is attached to one product so it will be unique.
Here is a snippet from the metadata class:
public partial class ProductMetadata
{
[DisplayName("Product Name")]
[Required(ErrorMessage = "Product Name is required.")]
public string ProductName { get; set; }
[DisplayName("Product Code")]
[Required(ErrorMessage = "Product Code is required.")]
[ProductCodeAlreadyExistsValidator(ErrorMessage = "This Product code is in use.")]
public string ProductCode { get; set; }
}
The 'ProductCodeAlreadyExistsValidator' works perfectly when creating a new product. The problem lies in editing an existing product as the validation is being performed on this attribute again, and it is finding itself in the database. This results in the validation failing.
Here is a snippet from the custom validator:
public class ProductCodeAlreadyExistsValidator : ValidationAttribute
{
private readonly object typeId = new object();
private const string defaultErrorMessage = "Product Code {0} is already present in the system.";
public ProductCodeAlreadyExistsValidator()
: base(defaultErrorMessage)
{
}
public override object TypeId
{
get
{
return typeId;
}
}
public string CustomerType { get; set; }
public string CustomerFriendlyType { get; set; }
public override string FormatErrorMessage(string roleName)
{
return String.Format(CultureInfo.CurrentUICulture, ErrorMessageString, roleName);
}
protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
if (!IsValid(value))
{
string errorMessage = string.Format(defaultErrorMessage, validationContext.MemberName, value as string);
return new ValidationResult(errorMessage, new string[] { validationContext.MemberName });
}
return null;
}
public override bool IsValid(object value)
{
bool alreadyPresent = false;
string ProductCode = value as string;
using (ModelContainer ctn = new ModelContainer())
{
alreadyPresent = ctn.Products.Where(t => t.ProductCode == ProductCode).Count() > 0;
}
return !alreadyPresent;
}
}
It might be a relatively simple fix however I seem to have hit a brick wall with it. Can anyone offer any advice?
Code seems ok to me. I think you need to identify if you are doing an insert or an update so the validation can ignore the checking when updating the field. You could check if the ID of the item editted is the same ID found by the code, it would be identified as a Editting.

Is there any way to force a model to be revalidated in an MVC3 controller?

I have a Model which contains an Address and Person twice, once for the "main" contact, and once for the "invoice" contact, and a boolean value called InvoiceContactSameAsMain - a clumsy name, but descriptive. The getter of the property checks to see if the Address and Contact objects for "main" and "invoice" are the same, and returns true if they are. The setter checks to see if the value is true, and if so, copies the main Person over the invoice Person , and the main Address over the invoice Address.
In my View, the boolean value is represented by a check box (as you'd expect). Attached to this is a small JS function which, if the check box is checked, hides the invoice fields and "switches off" the client-side validation by setting the data-val HTML attribute to false and forcing a re-parse of the unobtrusive validation attributes in the form. Un-checking the box naturally shows the fields and turns the validation back on.
All of this works fine, until I get to my Controller.
Despite the Model being "valid" and containing the correct fields (thanks to my InvoiceContactSameAsMain setter), ModelState.IsValid remains resolutely false, and I can't seem to find any way to revalidate the model. If I clear the ModelState, any and all errors disappear. I'd very much rather avoid digging through the fields in the ModelState by name, as the Person and Address objects are used throughout the project and may need to change or be extended at some point.
Is there something obvious I've missed here that will allow me to revalidate the ModelState? I've tried TryUpdateModel and TryValidateModel, but they both appear to use the cached ModelState values. I've even tried recursively calling my Action again, passing in the "fixed" model. I'm almost thankful that one didn't work.
Please let me know if any more detail or examples will help.
Edit: Obviously, if this is completely the wrong way to approach the problem, just let me know.
Edit 2: Added code samples as per Ron Sijm's suggestion.
The model is as follows:
public class Details
{
public int? UserID { get; set; }
public Company Company { get; set; }
public Address CompanyAddress { get; set; }
public Person MainPerson { get; set; }
public Address InvoiceAddress { get; set; }
public Person InvoiceContact { get; set; }
[Display(Name = "Promotional code")]
[StringLength(20, ErrorMessage = "Promotional code should not exceed 20 characters")]
public string PromotionalCode { get; set; }
[Display(Name = "Invoice contact same as main")]
public bool InvoiceContactSameasMain
{
get { return InvoiceContact.Equals(MainPerson); }
set
{
if (value)
{
InvoiceContact = MainPerson.Copy();
InvoiceAddress = CompanyAddress.Copy();
}
}
}
[_Common.MustAccept]
[Display(Name = "I agree with the Privacy Policy")]
public bool PrivacyFlag { get; set; }
[Display(Name = "Please subscribe to Sodexo News Letter")]
public bool MarketingOption { get; set; }
[Display(Name = "Contract number")]
public int? ContractNumber { get; set; }
public Details()
{
Company = new Company();
CompanyAddress = new Address();
MainPerson = new Person();
InvoiceAddress = new Address();
InvoiceContact = new Person();
}
}
This is wrapped in a ViewModel as there are a number of SelectLists involved in the page:
public class DetailsViewModel
{
public Details Details { get; set; }
public SelectList MainContactTitles { get; set; }
public SelectList InvoiceContactTitles { get; set; }
public SelectList SICCodes { get; set; }
public SelectList TypesOfBusiness { get; set; }
public SelectList NumbersOfEmployees { get; set; }
public DetailsViewModel()
{
}
}
The Controller's two relevant actions are as follows:
public class DetailsController : _ClientController
{
[Authorize]
public ActionResult Index()
{
DetailsViewModel viewModel = new DetailsViewModel();
if (Client == null)
{
viewModel.Details = DetailsFunctions.GetClient((int)UserId, null);
}
else
{
viewModel.Details = DetailsFunctions.GetClient((int)UserId, Client.ContractNumber);
}
viewModel.MainContactTitles = DetailsFunctions.GetTitles((int)UserId, viewModel.Details.MainPerson.title);
viewModel.InvoiceContactTitles = DetailsFunctions.GetTitles((int)UserId, viewModel.Details.InvoiceContact.title);
viewModel.SICCodes = DetailsFunctions.GetSICCodes(viewModel.Details.Company.sic_code);
viewModel.NumbersOfEmployees = DetailsFunctions.GetNumbersOfEmployees(viewModel.Details.Company.number_of_employees);
viewModel.TypesOfBusiness = DetailsFunctions.GetTypesOfBusiness(viewModel.Details.Company.public_private);
return View(viewModel);
}
[Authorize]
[HttpPost]
public ActionResult Index(DetailsViewModel ViewModel)
{
if (ModelState.IsValid)
{
//go to main page for now
DetailsFunctions.SetClient((int)UserId, ViewModel.Details);
return RedirectToAction("Index", "Home");
}
else
{
ViewModel.MainContactTitles = DetailsFunctions.GetTitles((int)UserId, ViewModel.Details.MainPerson.title);
ViewModel.InvoiceContactTitles = DetailsFunctions.GetTitles((int)UserId, ViewModel.Details.InvoiceContact.title);
ViewModel.SICCodes = DetailsFunctions.GetSICCodes(ViewModel.Details.Company.sic_code);
ViewModel.NumbersOfEmployees = DetailsFunctions.GetNumbersOfEmployees(ViewModel.Details.Company.number_of_employees);
ViewModel.TypesOfBusiness = DetailsFunctions.GetTypesOfBusiness(ViewModel.Details.Company.public_private);
return View(ViewModel);
}
}
}
I can provide the view and JS if needs be, but as the Model binding is all working just fine, I'm not sure how much help that is.
It's a moderately crap hack, but I've ended up just clearing the ModelState errors for the relevant fields in the controller before checking ModelState.IsValid:
if(ViewModel.Details.InvoiceContactSameasMain)
{
//iterate all ModelState values, grabbing the keys we want to clear errors from
foreach (string Key in ModelState.Keys)
{
if (Key.StartsWith("Details.InvoiceContact") || Key.Startwith("Details.InvoiceAddress"))
{
ModelState[Key].Errors.Clear();
}
}
}
The only upside is, if the Person or Address objects change, this code won't need to be altered.

asp.net mvc2 validations

I am using DataAnnotations for validation (including client side)
I have a form with multiple fields. Basic validation for individual fields work fine. Now there are a couple of fields of which atleast one needs to have a value (if there are 3 fields then either 1st or 2nd or 3rd field should have a value).
I have read quite a few posts on this site and couple of blog entries. But I couldn't find a solution that works in the above mentioned scenario. I might have missed something or doing it incorrectly.
Can you help with this please?
try this
[AttributeUsage(AttributeTargets.Class, AllowMultiple = true, Inherited = true)]
public sealed class EitherOr : ValidationAttribute
{
private const string _defaultErrorMessage = "'{0}' OR '{1}' OR '{2}' must have a value";
private readonly object _typeId = new object();
public EitherOr(string prop1, string prop2, string prop3)
: base(_defaultErrorMessage)
{
Prop1 = prop1;
Prop2 = prop2;
Prop3 = prop3;
}
public string Prop1 { get; private set; }
public string Prop2 { get; private set; }
public string Prop3 { get; private set; }
public override object TypeId
{
get
{
return _typeId;
}
}
public override string FormatErrorMessage(string name)
{
return String.Format(CultureInfo.CurrentUICulture, ErrorMessageString, Prop1, Prop2,Prop3);
}
public override bool IsValid(object value)
{
if(string.IsNullOrEmpty(Prop1)&&string.IsNullOrEmpty(Prop2) && string.IsNullOrEmpty(Prop3))
{
return false;
}
return true;
}
then mark your class with the EitherOr attribute:
[EitherOr("Bar","Stool","Hood", ErrorMessage = "please supply one of the properties")]
public class Foo
{
public string Bar{ get; set;}
public string Stool{ get; set;}
public string Hood{ get; set;}
}
Please note that i made use of string properties, if your property is of other type, makle sure to change the IsValid(object value) validation

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