attribute dependent on another field
Solution 1
Take a look at this: http://blogs.msdn.com/b/simonince/archive/2010/06/04/conditional-validation-in-mvc.aspx
I've modded the code somewhat to suit my needs. Perhaps you benefit from those changes as well.
public class RequiredIfAttribute : ValidationAttribute
{
private RequiredAttribute innerAttribute = new RequiredAttribute();
public string DependentUpon { get; set; }
public object Value { get; set; }
public RequiredIfAttribute(string dependentUpon, object value)
{
this.DependentUpon = dependentUpon;
this.Value = value;
}
public RequiredIfAttribute(string dependentUpon)
{
this.DependentUpon = dependentUpon;
this.Value = null;
}
public override bool IsValid(object value)
{
return innerAttribute.IsValid(value);
}
}
public class RequiredIfValidator : DataAnnotationsModelValidator<RequiredIfAttribute>
{
public RequiredIfValidator(ModelMetadata metadata, ControllerContext context, RequiredIfAttribute attribute)
: base(metadata, context, attribute)
{ }
public override IEnumerable<ModelClientValidationRule> GetClientValidationRules()
{
// no client validation - I might well blog about this soon!
return base.GetClientValidationRules();
}
public override IEnumerable<ModelValidationResult> Validate(object container)
{
// get a reference to the property this validation depends upon
var field = Metadata.ContainerType.GetProperty(Attribute.DependentUpon);
if (field != null)
{
// get the value of the dependent property
var value = field.GetValue(container, null);
// compare the value against the target value
if ((value != null && Attribute.Value == null) || (value != null && value.Equals(Attribute.Value)))
{
// match => means we should try validating this field
if (!Attribute.IsValid(Metadata.Model))
// validation failed - return an error
yield return new ModelValidationResult { Message = ErrorMessage };
}
}
}
}
Then use it:
public DateTime? DeptDateTime { get; set; }
[RequiredIf("DeptDateTime")]
public string DeptAirline { get; set; }
Solution 2
Just use the Foolproof validation library that is available on Codeplex: https://foolproof.codeplex.com/
It supports, amongst others, the following "requiredif" validation attributes / decorations:
[RequiredIf]
[RequiredIfNot]
[RequiredIfTrue]
[RequiredIfFalse]
[RequiredIfEmpty]
[RequiredIfNotEmpty]
[RequiredIfRegExMatch]
[RequiredIfNotRegExMatch]
To get started is easy:
- Download the package from the provided link
- Add a reference to the included .dll file
- Import the included javascript files
- Ensure that your views references the included javascript files from within its HTML for unobtrusive javascript and jquery validation.
Solution 3
Using NuGet Package Manager I intstalled this: https://github.com/jwaliszko/ExpressiveAnnotations
And this is my Model:
using ExpressiveAnnotations.Attributes;
public bool HasReferenceToNotIncludedFile { get; set; }
[RequiredIf("HasReferenceToNotIncludedFile == true", ErrorMessage = "RelevantAuditOpinionNumbers are required.")]
public string RelevantAuditOpinionNumbers { get; set; }
I guarantee you this will work!
Solution 4
I have not seen anything out of the box that would allow you to do this.
I've created a class for you to use, it's a bit rough and definitely not flexible.. but I think it may solve your current problem. Or at least put you on the right track.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations;
using System.Globalization;
namespace System.ComponentModel.DataAnnotations
{
[AttributeUsage(AttributeTargets.Class, AllowMultiple = true, Inherited = true)]
public sealed class RequiredIfAttribute : ValidationAttribute
{
private const string _defaultErrorMessage = "'{0}' is required";
private readonly object _typeId = new object();
private string _requiredProperty;
private string _targetProperty;
private bool _targetPropertyCondition;
public RequiredIfAttribute(string requiredProperty, string targetProperty, bool targetPropertyCondition)
: base(_defaultErrorMessage)
{
this._requiredProperty = requiredProperty;
this._targetProperty = targetProperty;
this._targetPropertyCondition = targetPropertyCondition;
}
public override object TypeId
{
get
{
return _typeId;
}
}
public override string FormatErrorMessage(string name)
{
return String.Format(CultureInfo.CurrentUICulture, ErrorMessageString, _requiredProperty, _targetProperty, _targetPropertyCondition);
}
public override bool IsValid(object value)
{
bool result = false;
bool propertyRequired = false; // Flag to check if the required property is required.
PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(value);
string requiredPropertyValue = (string) properties.Find(_requiredProperty, true).GetValue(value);
bool targetPropertyValue = (bool) properties.Find(_targetProperty, true).GetValue(value);
if (targetPropertyValue == _targetPropertyCondition)
{
propertyRequired = true;
}
if (propertyRequired)
{
//check the required property value is not null
if (requiredPropertyValue != null)
{
result = true;
}
}
else
{
//property is not required
result = true;
}
return result;
}
}
}
Above your Model class, you should just need to add:
[RequiredIf("retirementAge", "retired", true)]
public class MyModel
In your View
<%= Html.ValidationSummary() %>
Should show the error message whenever the retired property is true and the required property is empty.
Hope this helps.
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Ahmet Dalyan
Updated on July 09, 2022Comments
-
Ahmet Dalyan almost 2 years
In a model of my ASP.NET MVC application I would like validate a textbox as required only if a specific checkbox is checked.
Something like
public bool retired {get, set}; [RequiredIf("retired",true)] public string retirementAge {get, set};
How can I do that?
Thank you.
-
jwaliszko almost 10 years
[RequiredIf("retired == true")]
, more here
-
-
tkerwood about 12 yearsyou need to add ' DataAnnotationsModelValidatorProvider.RegisterAdapter( typeof(RequiredIfAttribute), typeof(RequiredIfValidator));' to your global.asax.cs to get this to work. (as described in the link RickardN provided.
-
Ian Kemp over 10 yearsWould be nice if you could provide a complete project in your repo, that includes all the required references like System.Linq.Dynamic. Furthermore you seem to be using a custom version of System.Linq.Dynamic as the Microsoft one has an
ExpressionParser.Parse()
method that takes 1 argument, but you are calling a 2-argument version. -
karaxuna over 10 yearsThanks @IanKemp, I'll consider your suggestions and improve repository
-
Admin about 10 yearsLink? It seems to be working fine for me - I'm using EF 6. I downloaded the sourcecode for Foolproof and compiled it myself so perhaps that explains why it is working for me?
-
David Poxon about 10 years
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Shivani about 8 yearsCan I use: [RequiredIfTrue] [RequiredIfFalse] - on single property with 2 different dependent properties?Example: [RequiredIfFalse("IsQuote", ErrorMessage = @"Provider must be entered.")] [RequiredIfTrue("IsIfa", ErrorMessage = @"Provider must be entered.")] [XmlElement("Provider", IsNullable = true)] public string Provider { get; set; }
-
Admin about 8 yearsMost probably. My recommendation is to make the change and then run a unit test against it to see whether it works as intended.
-
3 rules over 7 years@karaxuna What do I do with ExpressionParser there is an error showing me on that?
-
Hanady over 6 years
ModelMetadata.FromLambdaExpression(ex, html.ViewData).IsRequired
is always returningfalse
even thought the dependent upon property is true/false -
Cory-G almost 6 yearsThe
if
after// compare the value against the target value
should instead read(value == null && Attribute.Value == null)
as the first part of the condition. (change!=
to==
)