RequiredIf Conditional Validation Attribute

Question

I was looking for some advice on the best way to go about implementing a validation attribute that does the following   Model  public class MyInputModel         Required      public int Id  get set        public string MyProperty1  get set       public string MyProperty2  get set       public bool MyProperty3  get set        I want to have atleast prop1 prop2 prop3 with a value and if prop3 is the only value filled it it should not equal false  How would i go about writing a validation attribute s   for this   Thanks for any help

User · Answer

Expanding on the notes from Adel Mourad and Dan Hunex, I amended the code to provide an example that only accepts values that do not match the given value.

I also found that I didn't need the JavaScript.

I added the following class to my Models folder:

public class RequiredIfNotAttribute : ValidationAttribute, IClientValidatable
{
    private String PropertyName { get; set; }
    private Object InvalidValue { get; set; }
    private readonly RequiredAttribute _innerAttribute;

    public RequiredIfNotAttribute(String propertyName, Object invalidValue)
    {
        PropertyName = propertyName;
        InvalidValue = invalidValue;
        _innerAttribute = new RequiredAttribute();
    }

    protected override ValidationResult IsValid(object value, ValidationContext context)
    {
        var dependentValue = context.ObjectInstance.GetType().GetProperty(PropertyName).GetValue(context.ObjectInstance, null);

        if (dependentValue.ToString() != InvalidValue.ToString())
        {
            if (!_innerAttribute.IsValid(value))
            {
                return new ValidationResult(FormatErrorMessage(context.DisplayName), new[] { context.MemberName });
            }
        }
        return ValidationResult.Success;
    }

    public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
    {
        var rule = new ModelClientValidationRule
        {
            ErrorMessage = ErrorMessageString,
            ValidationType = "requiredifnot",
        };
        rule.ValidationParameters["dependentproperty"] = (context as ViewContext).ViewData.TemplateInfo.GetFullHtmlFieldId(PropertyName);
        rule.ValidationParameters["invalidvalue"] = InvalidValue is bool ? InvalidValue.ToString().ToLower() : InvalidValue;

        yield return rule;
    }

I didn't need to make any changes to my view, but did make a change to the properties of my model:

    [RequiredIfNot("Id", 0, ErrorMessage = "Please select a Source")]
    public string TemplateGTSource { get; set; }

    public string TemplateGTMedium
    {
        get
        {
            return "Email";
        }
    }

    [RequiredIfNot("Id", 0, ErrorMessage = "Please enter a Campaign")]
    public string TemplateGTCampaign { get; set; }

    [RequiredIfNot("Id", 0, ErrorMessage = "Please enter a Term")]
    public string TemplateGTTerm { get; set; }

Hope this helps!

User · Answer

I know the topic was asked some time ago  but recently I had faced similar issue and found yet another  but in my opinion a more complete solution  I decided to implement mechanism which provides conditional attributes to calculate validation results based on other properties values and relations between them  which are defined in logical expressions    Using it you are able to achieve the result you asked about in the following manner    RequiredIf  MyProperty2    null  amp  amp  MyProperty3    false    public string MyProperty1   get  set      RequiredIf  MyProperty1    null  amp  amp  MyProperty3    false    public string MyProperty2   get  set      AssertThat  MyProperty1    null    MyProperty2    null    MyProperty3    true    public bool MyProperty3   get  set      More information about ExpressiveAnnotations library can be found here  It should simplify many declarative validation cases without the necessity of writing additional case-specific attributes or using imperative way of validation inside controllers

User · Answer

I had the same problem yesterday  but I did it in a very clean way which works for both client side and server side validation  Condition  Based on the value of other property in the model  you want to make another property required  Here is the code  public class RequiredIfAttribute   RequiredAttribute     private String PropertyName   get  set      private Object DesiredValue   get  set       public RequiredIfAttribute String propertyName  Object desiredvalue          PropertyName   propertyName      DesiredValue   desiredvalue         protected override ValidationResult IsValid object value  ValidationContext context          Object instance   context ObjectInstance      Type type   instance GetType        Object proprtyvalue   type GetProperty PropertyName  GetValue instance  null       if  proprtyvalue ToString      DesiredValue ToString                ValidationResult result   base IsValid value  context         return result            return ValidationResult Success         PropertyName is the property on which you want to make your condition DesiredValue is the particular value of the PropertyName  property  for which your other property has to be validated for required Say you have the following   public enum UserType     Admin    Regular    public class User     public UserType UserType  get set       RequiredIf  quot UserType quot  UserType Admin                ErrorMessageResourceName  quot PasswordRequired quot                  ErrorMessageResourceType   typeof ResourceString      public string Password   get  set       At last but not the least  register adapter for your attribute so that it can do client side validation   I put it in global asax  Application Start  DataAnnotationsModelValidatorProvider RegisterAdapter typeof RequiredIfAttribute                                                         typeof RequiredAttributeAdapter     EDITED Some people was complaining that the client side fires no matter what or it does not work  So I modified the above code to do conditional client side validation with Javascript as well  For this case you don t need to register adapter  public class RequiredIfAttribute   ValidationAttribute  IClientValidatable               private String PropertyName   get  set            private Object DesiredValue   get  set            private readonly RequiredAttribute  innerAttribute           public RequiredIfAttribute String propertyName  Object desiredvalue                        PropertyName   propertyName              DesiredValue   desiredvalue               innerAttribute   new RequiredAttribute                       protected override ValidationResult IsValid object value  ValidationContext context                        var dependentValue   context ObjectInstance GetType   GetProperty PropertyName  GetValue context ObjectInstance  null                if  dependentValue ToString      DesiredValue ToString                                  if    innerAttribute IsValid value                                         return new ValidationResult FormatErrorMessage context DisplayName   new     context MemberName                                                 return ValidationResult Success                     public IEnumerable lt ModelClientValidationRule gt  GetClientValidationRules ModelMetadata metadata  ControllerContext context                        var rule   new ModelClientValidationRule                               ErrorMessage   ErrorMessageString                  ValidationType    quot requiredif quot                              rule ValidationParameters  quot dependentproperty quot      context as ViewContext  ViewData TemplateInfo GetFullHtmlFieldId PropertyName               rule ValidationParameters  quot desiredvalue quot     DesiredValue is bool   DesiredValue ToString   ToLower     DesiredValue               yield return rule                   And finally the javascript   bundle it and renderit   put it in its own script file    validator unobtrusive adapters add  requiredif     dependentproperty    desiredvalue    function  options        options rules  requiredif     options params      options messages  requiredif     options message         validator addMethod  requiredif   function  value  element  parameters        var desiredvalue   parameters desiredvalue      desiredvalue    desiredvalue    null        desiredvalue  toString        var controlType      quot input id    quot    parameters dependentproperty    quot    quot   attr  quot type quot        var actualvalue          if  controlType     quot checkbox quot     controlType     quot radio quot             var control      quot input id    quot    parameters dependentproperty    quot    checked quot            actualvalue   control val          else           actualvalue      quot   quot    parameters dependentproperty  val              if    trim desiredvalue  toLowerCase         trim actualvalue  toLocaleLowerCase              var isValid     validator methods required call this  value  element  parameters           return isValid            return true       You need obviously the unobstrusive validate jQuery to be included as requirement

User · Answer

I got it to work on ASP NET MVC 5  I saw many people interested in and suffering from this code and i know it s really confusing and disrupting for the first time   Notes   worked on MVC 5 on both server and client side  D  I didn t install  ExpressiveAnnotations  library at all  I m taking about the Original code from   Dan Hunex   Find him above   Tips To Fix This Error      The type System Web Mvc RequiredAttributeAdapter must have a public constructor which accepts three parameters of types System Web Mvc ModelMetadata  System Web Mvc ControllerContext  and ExpressiveAnnotations Attributes RequiredIfAttribute Parameter name  adapterType    Tip  1  make sure that you re inheriting from  ValidationAttribute  not from  RequiredAttribute       public class RequiredIfAttribute   ValidationAttribute  IClientValidatable          Tip  2  OR remove this entire line from  Global asax   It is not needed at all in the newer version of the code  after edit by  Dan Hunex    and yes this line was a must in the old version      DataAnnotationsModelValidatorProvider RegisterAdapter typeof RequiredIfAttribute   typeof RequiredAttributeAdapter      Tips To Get The Javascript Code Part Work  1- put the code in a new js file  ex requiredIfValidator js   2- warp the code inside a   document  ready function                3- include our js file after including the JQuery validation libraries  So it look like this now     Scripts Render    bundles jqueryval    lt script src    Content JS requiredIfValidator js  gt  lt  script gt    4- Edit the C  code   from  rule ValidationParameters  dependentproperty      context as ViewContext  ViewData TemplateInfo GetFullHtmlFieldId PropertyName     to  rule ValidationParameters  dependentproperty     PropertyName    and from  if  dependentValue ToString      DesiredValue ToString      to  if  dependentValue    null  amp  amp  dependentValue ToString      DesiredValue ToString      My Entire Code Up and Running  Global asax  Nothing to add here  keep it clean  requiredIfValidator js  create this file in   content or in   scripts folder        validator unobtrusive adapters add  requiredif     dependentproperty    desiredvalue    function  options        options rules  requiredif     options params      options messages  requiredif     options message          document  ready function             validator addMethod  requiredif   function  value  element  parameters            var desiredvalue   parameters desiredvalue          desiredvalue    desiredvalue    null        desiredvalue  toString            var controlType      input id       parameters dependentproperty         attr  type            var actualvalue              if  controlType     checkbox     controlType     radio                 var control      input id       parameters dependentproperty       checked                actualvalue   control val              else               actualvalue           parameters dependentproperty  val                      if    trim desiredvalue  toLowerCase         trim actualvalue  toLocaleLowerCase                  var isValid     validator methods required call this  value  element  parameters               return isValid                    return true                 Layout cshtml or the View   Scripts Render    bundles jqueryval    lt script src    Content JS requiredIfValidator js  gt  lt  script gt    RequiredIfAttribute cs Class  create it some where in your project  For example in   models customValidation       using System  using System Collections Generic  using System ComponentModel DataAnnotations  using System Web Mvc   namespace Your Project Name Models CustomValidation       public class RequiredIfAttribute   ValidationAttribute  IClientValidatable               private String PropertyName   get  set            private Object DesiredValue   get  set            private readonly RequiredAttribute  innerAttribute           public RequiredIfAttribute String propertyName  Object desiredvalue                        PropertyName   propertyName              DesiredValue   desiredvalue               innerAttribute   new RequiredAttribute                       protected override ValidationResult IsValid object value  ValidationContext context                        var dependentValue   context ObjectInstance GetType   GetProperty PropertyName  GetValue context ObjectInstance  null                if  dependentValue    null  amp  amp  dependentValue ToString      DesiredValue ToString                                  if    innerAttribute IsValid value                                         return new ValidationResult FormatErrorMessage context DisplayName   new     context MemberName                                                 return ValidationResult Success                     public IEnumerable lt ModelClientValidationRule gt  GetClientValidationRules ModelMetadata metadata  ControllerContext context                        var rule   new ModelClientValidationRule                               ErrorMessage   ErrorMessageString                  ValidationType    requiredif                              rule ValidationParameters  dependentproperty     PropertyName              rule ValidationParameters  desiredvalue     DesiredValue is bool   DesiredValue ToString   ToLower     DesiredValue               yield return rule                      The Model       using System  using System Collections Generic  using System ComponentModel DataAnnotations  using System Linq  using System Web  using Your Project Name Models CustomValidation   namespace Your Project Name Models ViewModels        public class CreateOpenActivity               public Nullable lt int gt  ORG BY CD   get  set              RequiredIf  ORG BY CD    5   ErrorMessage    Coordinator ID is required       This means  IF  ORG BY CD  is equal 5  for the example    gt  make  COR CI ID NUM  required and apply its all validation   data annotations          RegularExpression   0-9     ErrorMessage    Enter Numbers Only             MaxLength 9  ErrorMessage    Enter a valid ID Number             MinLength 9  ErrorMessage    Enter a valid ID Number            public string COR CI ID NUM   get  set              The View  Nothing to note here actually           model Your Project Name Models ViewModels CreateOpenActivity        ViewBag Title    Testing       using  Html BeginForm            Html AntiForgeryToken         lt div class  form-horizontal  gt           lt h4 gt CreateOpenActivity lt  h4 gt           lt hr   gt           Html ValidationSummary true      new    class    text-danger               lt div class  form-group  gt               Html LabelFor model   gt  model ORG BY CD  htmlAttributes  new    class    control-label col-md-2                  lt div class  col-md-10  gt                   Html EditorFor model   gt  model ORG BY CD  new   htmlAttributes   new    class    form-control                        Html ValidationMessageFor model   gt  model ORG BY CD      new    class    text-danger                  lt  div gt           lt  div gt            lt div class  form-group  gt               Html LabelFor model   gt  model COR CI ID NUM  htmlAttributes  new    class    control-label col-md-2                  lt div class  col-md-10  gt                   Html EditorFor model   gt  model COR CI ID NUM  new   htmlAttributes   new    class    form-control                        Html ValidationMessageFor model   gt  model COR CI ID NUM      new    class    text-danger                  lt  div gt           lt  div gt            lt div class  form-group  gt               lt div class  col-md-offset-2 col-md-10  gt                   lt input type  submit  value  Create  class  btn btn-default    gt               lt  div gt           lt  div gt       lt  div gt      I may upload a project sample for this later      Hope this was helpful  Thank You

User · Answer

If you try to use  ModelState Remove  or  ModelState  Prop   Errors Clear    the  ModelState IsValid  stil returns false   Why not just removing the default  Required  Annotation from Model and make your custom validation before the  ModelState IsValid  on Controller  Post  action  Like this   if   String IsNullOrEmpty yourClass Property1   amp  amp  String IsNullOrEmpty yourClass dependantProperty                           ModelState AddModelError  dependantProperty    It  s necessary to select some  dependant

User · Answer

The main difference from other solutions here is that this one reuses logic in RequiredAttribute on the server side  and uses required s validation method depends property on the client side   public class RequiredIf   RequiredAttribute  IClientValidatable       public string OtherProperty   get  private set        public object OtherPropertyValue   get  private set         public RequiredIf string otherProperty  object otherPropertyValue                OtherProperty   otherProperty          OtherPropertyValue   otherPropertyValue             protected override ValidationResult IsValid object value  ValidationContext validationContext                PropertyInfo otherPropertyInfo   validationContext ObjectType GetProperty OtherProperty           if  otherPropertyInfo    null                        return new ValidationResult   Unknown property  OtherProperty                        object otherValue   otherPropertyInfo GetValue validationContext ObjectInstance  null           if  Equals OtherPropertyValue  otherValue      if other property has the configured value             return base IsValid value  validationContext            return null             public IEnumerable lt ModelClientValidationRule gt  GetClientValidationRules ModelMetadata metadata  ControllerContext context                var rule   new ModelClientValidationRule            rule ErrorMessage   FormatErrorMessage metadata GetDisplayName             rule ValidationType    requiredif      data-val-requiredif         rule ValidationParameters Add  other   OtherProperty      data-val-requiredif-other         rule ValidationParameters Add  otherval   OtherPropertyValue      data-val-requiredif-otherval          yield return rule             validator unobtrusive adapters add  requiredif     other    otherval    function  options        var value             depends  function                  var element     options form  find   input name      options params other         0               return element  amp  amp    element  val      options params otherval                      options rules  required     value      options messages  required     options message

[asp.net-mvc-3] RequiredIf Conditional Validation Attribute

Examples related to asp.net-mvc-3

Examples related to validationattribute