I am using JsonSerializer to Deserialize a post request from a client. The class for serialization contains non-null and required properties. The Json serializer ignores the constructor and the non-null types and passes it the null value.
Current: non-nullable fields sets as null
Expected: throw an exception
How can I fix this? Maybe there is some attribute or parameter
{
"time": [250, 500, 1000]
}
[Serializable]
public class ArchiveData
{
[JsonConstructor]
public ArchiveData(long[] time, SensorArchiveValues[] sensorsArchiveValues)
{
Time = time;
SensorsArchiveValues = sensorsArchiveValues;
}
[BsonId]
[BsonRepresentation(BsonType.ObjectId)]
public string Id { get; set; }
[Required]
public long[] Time { get; set; }
[Required]
public SensorArchiveValues[] SensorsArchiveValues { get; set; }
}
it is better to fix the class, but if you can not change it , try this code
using Newtonsoft.Json;
var jsonParsed = JObject.Parse(json).Dump();
long[] time = jsonParsed["time"].ToObject<long[]>();
SensorArchiveValues[] sensorsArchiveValues = null;
if (jsonParsed["sensorsArchiveValues"] != null)
sensorsArchiveValues = jsonParsed["sensorsArchiveValues"].ToObject<SensorArchiveValues[]>();
// and maybe
// else sensorsArchiveValues = Array.Empty<SensorArchiveValues>();
var archiveData = new ArchiveData(time,sensorsArchiveValues);
Related
My AppConfig.json:
{
"MyTimeZone: "CET",
"RegularString" : "SomeValue",
"AnArray" : ["1","2"]
}
My POCO class:
public class Settings
{
public TimeZoneInfo MyTimeZone { get; set; }
public string RegularString { get; set; }
public IList<string> AnArray { get; set; }
}
Registry.cs:
var configuration = GetConfiguration("AppSettings.json");
services.Configure<Settings>(configuration.GetSection("Settings"));
This of course does not bind "CET" into a valid TimeZoneInfo object. Now the question is what is the best place in my application (a web app) to convert from string to TimeZoneInfo? Is there a way to automatically convert string config values to objects based on certain rules without creating custom converters?
Reference Use DI services to configure options
services.AddOptions<Settings>()
.Configure<IConfiguration>((setting, configuration) => {
var section = config.GetSection("Settings");
//This will populate the other properties that can bind by default
section.Bind(setting);
//this will extract the remaining value and set it mnually
string value = section.GetValue<string>("MyTimeZone");
TimeZoneInfo info = TimeZoneInfo.FindSystemTimeZoneById(value);
setting.MyTimeZone = info;
});
The complex setting value can be extracted directly from configuration via DI and used to create the time zone and apply it to the settings.
It just my personal opinion but I prefer the MyTimeZone to be a json object instead only a string. Consider the following:
"Settings": {
"MyTimeZone": {
"ConfigureTimeZoneById": "CET"
},
"RegularString": "SomeValue",
"AnArray": [ "1", "2" ]
}
MyTimeZone.ConfigureTimeZoneById is not part of the actual data object. It's just proxy to bind object to configuration. This how TimeZone class might look like:
public class TimeZone
{
private string configureTimeZoneById { get; set; }
public string ConfigureTimeZoneById
{
get { return configureTimeZoneById; }
set
{
configureTimeZoneById = value;
InitializeTimeZone(value);
}
}
public string TimeZoneId { get; set; }
public string OtherProperties { get; set; }
private void InitializeTimeZone(string id)
{
var getTimeZone = TimeZonesDataset().FirstOrDefault(tzon => tzon.TimeZoneId.Equals(id));
if (getTimeZone != null)
{
this.TimeZoneId = getTimeZone.TimeZoneId;
this.OtherProperties = getTimeZone.OtherProperties;
}
}
//dummy dataset
private List<TimeZone> TimeZonesDataset() => new List<TimeZone> {
new TimeZone{TimeZoneId = "CET", OtherProperties = "Dummy properties to prove point"},
new TimeZone{TimeZoneId = "GMT", OtherProperties = default},
};
We have some configuration files which were generated by serializing C# objects with Json.net.
We'd like to migrate one property of the serialised class away from being a simple enum property into a class property.
One easy way to do this, would be to leave the old enum property on the class, and arrange for Json.net to read this property when we load the config, but not to save it again when we next serialize the object. We'll deal with generating the new class from the old enum separately.
Is there any simple way to mark (e.g. with attributes) a property of a C# object, so that Json.net will ignore it ONLY when serializing, but attend to it when deserializing?
There are actually several fairly simple approaches you can use to achieve the result you want.
Let's assume, for example, that you have your classes currently defined like this:
class Config
{
public Fizz ObsoleteSetting { get; set; }
public Bang ReplacementSetting { get; set; }
}
enum Fizz { Alpha, Beta, Gamma }
class Bang
{
public string Value { get; set; }
}
And you want to do this:
string json = #"{ ""ObsoleteSetting"" : ""Gamma"" }";
// deserialize
Config config = JsonConvert.DeserializeObject<Config>(json);
// migrate
config.ReplacementSetting =
new Bang { Value = config.ObsoleteSetting.ToString() };
// serialize
json = JsonConvert.SerializeObject(config);
Console.WriteLine(json);
To get this:
{"ReplacementSetting":{"Value":"Gamma"}}
Approach 1: Add a ShouldSerialize method
Json.NET has the ability to conditionally serialize properties by looking for corresponding ShouldSerialize methods in the class.
To use this feature, add a boolean ShouldSerializeBlah() method to your class where Blah is replaced with the name of the property that you do not want to serialize. Make the implementation of this method always return false.
class Config
{
public Fizz ObsoleteSetting { get; set; }
public Bang ReplacementSetting { get; set; }
public bool ShouldSerializeObsoleteSetting()
{
return false;
}
}
Note: if you like this approach but you don't want to muddy up the public interface of your class by introducing a ShouldSerialize method, you can use an IContractResolver to do the same thing programmatically. See Conditional Property Serialization in the documentation.
Approach 2: Manipulate the JSON with JObjects
Instead of using JsonConvert.SerializeObject to do the serialization, load the config object into a JObject, then simply remove the unwanted property from the JSON before writing it out. It's just a couple of extra lines of code.
JObject jo = JObject.FromObject(config);
// remove the "ObsoleteSetting" JProperty from its parent
jo["ObsoleteSetting"].Parent.Remove();
json = jo.ToString();
Approach 3: Clever (ab)use of attributes
Apply a [JsonIgnore] attribute to the property that you do not want to be serialized.
Add an alternate, private property setter to the class with the same type as the original property. Make the implementation of that property set the original property.
Apply a [JsonProperty] attribute to the alternate setter, giving it the same JSON name as the original property.
Here is the revised Config class:
class Config
{
[JsonIgnore]
public Fizz ObsoleteSetting { get; set; }
[JsonProperty("ObsoleteSetting")]
private Fizz ObsoleteSettingAlternateSetter
{
// get is intentionally omitted here
set { ObsoleteSetting = value; }
}
public Bang ReplacementSetting { get; set; }
}
For any situation where it's acceptable to have your deserialization-only property be marked internal, there's a remarkably simple solution that doesn't depend on attributes at all. Simply mark the property as internal get, but public set:
public class JsonTest {
public string SomeProperty { internal get; set; }
}
This results in correct deserialization using default settings/resolvers/etc., but the property is stripped from serialized output.
I like sticking with attributes on this one, here is the method I use when needing to deserialize a property but not serialize it or vice versa.
STEP 1 - Create the custom attribute
public class JsonIgnoreSerializationAttribute : Attribute { }
STEP 2 - Create a custom Contract Reslover
class JsonPropertiesResolver : DefaultContractResolver
{
protected override List<MemberInfo> GetSerializableMembers(Type objectType)
{
//Return properties that do NOT have the JsonIgnoreSerializationAttribute
return objectType.GetProperties()
.Where(pi => !Attribute.IsDefined(pi, typeof(JsonIgnoreSerializationAttribute)))
.ToList<MemberInfo>();
}
}
STEP 3 - Add attribute where serialization is not needed but deserialization is
[JsonIgnoreSerialization]
public string Prop1 { get; set; } //Will be skipped when serialized
[JsonIgnoreSerialization]
public string Prop2 { get; set; } //Also will be skipped when serialized
public string Prop3 { get; set; } //Will not be skipped when serialized
STEP 4 - Use it
var sweet = JsonConvert.SerializeObject(myObj, new JsonSerializerSettings { ContractResolver = new JsonPropertiesResolver() });
Hope this helps! Also it's worth noting that this will also ignore the properties when Deserialization happens, when I am derserializing I just use the converter in the conventional way.
JsonConvert.DeserializeObject<MyType>(myString);
Use setter property:
[JsonProperty(nameof(IgnoreOnSerializing))]
public string IgnoreOnSerializingSetter { set { _ignoreOnSerializing = value; } }
[JsonIgnore]
private string _ignoreOnSerializing;
[JsonIgnore]
public string IgnoreOnSerializing
{
get { return this._ignoreOnSerializing; }
set { this._ignoreOnSerializing = value; }
}
Hope this help.
After i spent a quite long time searching how to flag a class property to be De-Serializable and NOT Serializable i found that there's no such thing to do that at all; so i came up with a solution that combines two different libraries or serialization techniques (System.Runtime.Serialization.Json & Newtonsoft.Json) and it worked for me like the following:
flag all your class and sub-classes as "DataContract".
flag all the properties of your class and sub-classes as "DataMember".
flag all the properties of your class and sub-classes as "JsonProperty" except those you want them not to be serialized.
now flag the properties the you do NOT want it to be serialized as "JsonIgnore".
then Serialize using "Newtonsoft.Json.JsonConvert.SerializeObject" and De-Serialize using "System.Runtime.Serialization.Json.DataContractJsonSerializer".
using System;
using System.Collections.Generic;
using Newtonsoft.Json;
using System.Runtime.Serialization;
using System.IO;
using System.Runtime.Serialization.Json;
using System.Text;
namespace LUM_Win.model
{
[DataContract]
public class User
{
public User() { }
public User(String JSONObject)
{
MemoryStream stream = new MemoryStream(Encoding.Unicode.GetBytes(JSONObject));
DataContractJsonSerializer dataContractJsonSerializer = new DataContractJsonSerializer(typeof(User));
User user = (User)dataContractJsonSerializer.ReadObject(stream);
this.ID = user.ID;
this.Country = user.Country;
this.FirstName = user.FirstName;
this.LastName = user.LastName;
this.Nickname = user.Nickname;
this.PhoneNumber = user.PhoneNumber;
this.DisplayPicture = user.DisplayPicture;
this.IsRegistred = user.IsRegistred;
this.IsConfirmed = user.IsConfirmed;
this.VerificationCode = user.VerificationCode;
this.Meetings = user.Meetings;
}
[DataMember(Name = "_id")]
[JsonProperty(PropertyName = "_id")]
public String ID { get; set; }
[DataMember(Name = "country")]
[JsonProperty(PropertyName = "country")]
public String Country { get; set; }
[DataMember(Name = "firstname")]
[JsonProperty(PropertyName = "firstname")]
public String FirstName { get; set; }
[DataMember(Name = "lastname")]
[JsonProperty(PropertyName = "lastname")]
public String LastName { get; set; }
[DataMember(Name = "nickname")]
[JsonProperty(PropertyName = "nickname")]
public String Nickname { get; set; }
[DataMember(Name = "number")]
[JsonProperty(PropertyName = "number")]
public String PhoneNumber { get; set; }
[DataMember(Name = "thumbnail")]
[JsonProperty(PropertyName = "thumbnail")]
public String DisplayPicture { get; set; }
[DataMember(Name = "registered")]
[JsonProperty(PropertyName = "registered")]
public bool IsRegistred { get; set; }
[DataMember(Name = "confirmed")]
[JsonProperty(PropertyName = "confirmed")]
public bool IsConfirmed { get; set; }
[JsonIgnore]
[DataMember(Name = "verification_code")]
public String VerificationCode { get; set; }
[JsonIgnore]
[DataMember(Name = "meeting_ids")]
public List<Meeting> Meetings { get; set; }
public String toJSONString()
{
return JsonConvert.SerializeObject(this, new JsonSerializerSettings() { NullValueHandling = NullValueHandling.Ignore });
}
}
}
Hope that helps ...
Depending on where in the application this takes place and if it's just one property, one manual way you can do this is by setting the property value to null and then on the model you can specify that the property be ignored if the value is null:
[JsonProperty(NullValueHandling = NullValue.Ignore)]
public string MyProperty { get; set; }
If you are working on an ASP.NET Core web app, you can globally set this for all properties in all models by setting this in your Startup.cs file:
public void ConfigureServices(IServiceCollection services) {
// other configuration here
services.AddMvc()
.AddJsonOptions(options => options.SerializerSettings.NullValueHandling = NullValueHandling.Ignore);
}
with reference to #ThoHo's solution, using the setter is actually all that is needed, with no additional tags.
For me I previously had a single reference Id, that I wanted to load and add to the new collection of reference Ids. By changing the definition of the reference Id to only contain a setter method, which added the value to the new collection. Json can't write the value back if the Property doesn't have a get; method.
// Old property that I want to read from Json, but never write again. No getter.
public Guid RefId { set { RefIds.Add(value); } }
// New property that will be in use from now on. Both setter and getter.
public ICollection<Guid> RefIds { get; set; }
This class is now backwards compatible with the previous version and only saves the RefIds for the new versions.
To build upon Tho Ho's answer, this can also be used for fields.
[JsonProperty(nameof(IgnoreOnSerializing))]
public string IgnoreOnSerializingSetter { set { IgnoreOnSerializing = value; } }
[JsonIgnore]
public string IgnoreOnSerializing;
If you use JsonConvert,IgnoreDataMemberAttribute is ok.My standard library not refrence Newton.Json,and I use [IgnoreDataMember] to control object serialize.
From Newton.net help document.
Is there any simple way to mark (e.g. with attributes) a property of a C# object, so that Json.net will ignore it ONLY when serializing, but attend to it when deserializing?
The easiest way I've found as of this writing is to include this logic in your IContractResolver.
Sample code from above link copied here for posterity:
public class Employee
{
public string Name { get; set; }
public Employee Manager { get; set; }
public bool ShouldSerializeManager()
{
// don't serialize the Manager property if an employee is their own manager
return (Manager != this);
}
}
public class ShouldSerializeContractResolver : DefaultContractResolver
{
public new static readonly ShouldSerializeContractResolver Instance = new ShouldSerializeContractResolver();
protected override JsonProperty CreateProperty(MemberInfo member, MemberSerialization memberSerialization)
{
JsonProperty property = base.CreateProperty(member, memberSerialization);
if (property.DeclaringType == typeof(Employee) && property.PropertyName == "Manager")
{
property.ShouldSerialize =
instance =>
{
Employee e = (Employee)instance;
return e.Manager != e;
};
}
return property;
}
}
All of the answers are good but this approach seemed like the cleanest way. I actually implemented this by looking for an attribute on the property for SkipSerialize and SkipDeserialize so you can just mark up any class you control. Great question!
Jraco11's answer is very neat. In case, if you want to use the same IContractResolver both for serialization and deserialization, then you can use the following:
public class JsonPropertiesResolver : DefaultContractResolver
{
protected override JsonProperty CreateProperty(MemberInfo member, MemberSerialization memberSerialization)
{
JsonProperty property = base.CreateProperty(member, memberSerialization);
if (member.IsDefined(typeof(JsonIgnoreSerializationAttribute)))
{
property.ShouldSerialize = instance => false;
}
return property;
}
}
thats will do the trick, create a property with set only
example 1:
https://dotnetfiddle.net/IxMXcG
[JsonProperty("disabled-protections")]
public JArray DisabledProtections { set => IsPartialResult = (value != null && value.HasValues); }
public bool IsPartialResult { get; private set; }
example 2:
private JArray _disabledProtections;
[JsonProperty("disabled-protections")]
public JArray DisabledProtections { set => _disabledProtections = value; }
public bool IsPartialResult => _disabledProtections != null && _disabledProtections.HasValues;
Use [JsonIgnore] attribute in the public property of the model class.
With this DTO:
public class QuestionDTO {
public Guid Id { get; set; }
public string Prompt { get; set; }
public List<Answer> Choices { get; set; }
public QuestionDTO() {
}
public QuestionDTO(Question question) {
this.Id = question.Id;
this.Prompt = question.Prompt;
this.Choices = question.Choices;
}
}
I was getting an error about Unable to Parse without a parameterless constructor. I have since fixed that, but now my objects are de-serialized empty:
using System.Text.Json;
var results = JsonSerializer.Deserialize<List<QuestionDTO>>(jsonString);
The jsonString contains 3 items with the correct data, and the deserialized list contains 3 items, but all the properties are empty.
The new json library is case sensitive by default. You can change this by providing a settings option. Here is a sample:
private JsonSerializerOptions _options = new JsonSerializerOptions { PropertyNameCaseInsensitive = true }
private async Task SampleRequest()
{
var result = await HttpClient.GetStreamAsync(QueryHelpers.AddQueryString(queryString, queryParams));
_expenses = await JsonSerializer.DeserializeAsync<List<Common.Dtos.Expenses.Models.Querys.ExpensesItem>>(result, _options);
}
I'm looking for a reliable solution to log details of requests and responses made to and from our controllers. However, some of the data passing through contains sensitive information that should not be written to a log.
In the controller, the inbound request is bound to a single model from the request body, and as the request is answered, a single model is passed to the Ok() result like this (very simplified):
[HttpGet]
[Route("Some/Route")]
public IHttpActionResult SomeController([FromBody] RequestType requestObj)
{
ResponseType responseObj = GetResponse(requestObj)
return this.Ok(responseObj);
}
Now my goal is to somehow log the contents of the request and response object at the beginning and end of the controller, respectively. What I would like to do is bind the models first, then log out their attributes. An example of the RequestType is something like:
public class RequestType
{
public string SomeAttribute { get; set; }
public string AnotherAttribute { get; set; }
public string Password{ get; set; }
}
And the log would look something like:
[date-time] Request to SomeController:
SomeAttribute: "value_from_request"
AnotherAttribute: "another_value"
Password: "supersecret123"
Now clearly we don't want the password to be logged. So I would like to create a custom data annotation that would not log certain fields. Its use would look like this (updated RequestType):
public class RequestType
{
public string SomeAttribute { get; set; }
public string AnotherAttribute { get; set; }
[SensitiveData]
public string Password{ get; set; }
}
Where would I start with this? I'm not incredibly familliar with .NET, but know that there are many sort of magic classes that can be subclassed to override some of their functionality. Is there any such class that can help here? Even better, is there any way to do this during the model binding? So we could catch errors that occur during model binding as well?
We should be able to achieve what you're looking for with an ActionFilterAttribute.
Capture Requests Attribute
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = false)]
public sealed class CaptureRequestsAttribute : ActionFilterAttribute // *IMPORTANT* This is in the System.Web.Http.Filters namespace, not System.Web.Mvc
{
public override void OnActionExecuting(HttpActionContext actionContext)
{
var messages = actionContext.ActionArguments.Select(arg => GetLogMessage(arg.Value));
var logMessage = $"[{DateTime.Now}] Request to " +
$"{actionContext.ControllerContext.Controller}]:\n{string.Join("\n", messages)}";
WriteToLog(logMessage);
base.OnActionExecuting(actionContext);
}
public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
{
var result = actionExecutedContext.Response.Content as ObjectContent;
var message = GetLogMessage(result?.Value);
var logMessage = $"[{DateTime.Now}] Response from " +
$"{actionExecutedContext.ActionContext.ControllerContext.Controller}:\n{message}";
WriteToLog(logMessage);
base.OnActionExecuted(actionExecutedContext);
}
private static void WriteToLog(string message)
{
// todo: write you logging stuff here
}
private static string GetLogMessage(object objectToLog)
{
if (objectToLog == null)
{
return string.Empty;
}
var type = objectToLog.GetType();
var properties = type.GetProperties();
if (properties.Length == 0)
{
return $"{type}: {objectToLog}";
}
else
{
var nonSensitiveProperties = type
.GetProperties()
.Where(IsNotSensitiveData)
.Select(property => $"{property.Name}: {property.GetValue(objectToLog)}");
return string.Join("\n", nonSensitiveProperties);
}
}
private static bool IsNotSensitiveData(PropertyInfo property) =>
property.GetCustomAttributes<SensitiveDataAttribute>().Count() == 0;
}
Sensitive Data Attribute
[AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
public sealed class SensitiveDataAttribute : Attribute
{
}
Then, you can just add it to your WebApi controller (or a specific method in it):
[CaptureRequests]
public class ValuesController : ApiController
{
// .. methods
}
And finally your models can just add the SensitiveDataAttribute:
public class TestModel
{
public string Username { get; set; }
[SensitiveData]
public string Password { get; set; }
}
This does not make use of DataAnnotations,however, One way that comes to mind would be to use the serialization. If your payload is within a reasonable size you could serialize and deserialize your RequestType class when reading and writing to/from a log. This would require a custom serialization format or making use of the default, xml.
[Seriliazeble()]
public class RequestType
{
public string SomeAttribute { get; set; }
public string AnotherAttribute { get; set; }
[NonSerialized()]
public string Password{ get; set; }
}
Using the above attribute will omit Password from serialization. Then you copuld proceed to Logger.Log(MySerializer.Serialize(MyRequest)); and your sensitive data will be omitted.
This link describes the approach in detail.
For xml serialization, simply use the XmlSerializer class.
public class MySerializationService
{
public string SerializeObject(object item)
{
XmlSerializer serializer = new XmlSerializer(item.GetType());
System.IO.MemoryStream aMemStr = new System.IO.MemoryStream();
System.Xml.XmlTextWriter writer = new System.Xml.XmlTextWriter(aMemStr, null);
serializer.Serialize(writer, item);
string strXml = System.Text.Encoding.UTF8.GetString(aMemStr.ToArray());
return strXml;
}
public object DeSerializeObject(Type objectType, string objectString)
{
object obj = null;
XmlSerializer xs = new XmlSerializer(objectType);
obj = xs.Deserialize(new StringReader(objectString));
return obj;
}
}
Then using the above or similar methods you can read and write in a custom format.
Write :
string logData=new MySerializationService().SerializeObject(myRequest);
Read :
RequestType loggedRequest= (RequestType)new MySerializationService().DeSerializeObject(new RequestType().GetType(), logData);
I have a model with properties that look like this:
public class YourDetails {
[Required(ErrorMessage = "Code is required")]
[StringLength(10, ErrorMessage = "Code length is wrong", MinimumLength = 2)]
[Range(0, int.MaxValue, ErrorMessage = "Please enter a value bigger than {1}")]
public int Code { get; set; }
}
The UI validation is setup the usual out of the box way with unobtrusive JS validation plugin.
The issue: I have 2 navigation actions, back and next. Next is fine, validation fires when things are wrong, and when things are right i.e. .isValid() returns true, the data is passed to the DB service etc etc.
However when I press 'back' I have a requirement to validate the form/ViewModel differently prior to saving. I.e. make sure Code is a positive integer, but don't bother with the Required or StringLength validation.
So basically I want to validate fully on Next but partially on Back. Is that possible?
When I've done something similar in the past the easiest way i found was to use fluent validation http://fluentvalidation.codeplex.com/wikipage?title=mvc. You can pass parameters to the validator and switch to different rule sets.
I've used the following conditional "Required" & "StringLength" attributes in the past and they work well.
Required If Attribute:
using System;
using System.ComponentModel.DataAnnotations;
using System.Reflection;
namespace Website.Core.Mvc.DataAnnotations
{
[AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = true)]
public class RequiredIfAttribute : RequiredAttribute
{
public string OtherProperty { get; set; }
public object OtherPropertyValue { get; set; }
public RequiredIfAttribute(string otherProperty, object value)
: base()
{
OtherProperty = otherProperty;
OtherPropertyValue = value;
}
private object _TypeId = new object();
public override object TypeId
{
get
{
return _TypeId;
}
}
protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
PropertyInfo property = validationContext.ObjectType.GetProperty(this.OtherProperty);
if (property == null)
{
return new ValidationResult(this.OtherProperty + " not found");
}
// Get
object actualOtherPropertyValue = property.GetValue(validationContext.ObjectInstance, null);
// If the other property matches the expected value then validate as normal
if (IsRequired(OtherPropertyValue, actualOtherPropertyValue))
{
// Call base and validate required as normal
ValidationResult isValid = base.IsValid(value, validationContext);
return isValid;
}
return ValidationResult.Success;
}
protected virtual bool IsRequired(object otherPropertyValue, object actualOtherPropertyValue)
{
return object.Equals(OtherPropertyValue, actualOtherPropertyValue);
}
}
}
String Length If Attribute:
using System.ComponentModel.DataAnnotations;
using System.Reflection;
namespace Website.Core.Mvc.DataAnnotations
{
public class StringLengthIfAttribute : StringLengthAttribute
{
public string OtherProperty { get; set; }
public object OtherPropertyValue { get; set; }
public StringLengthIfAttribute(int maximumLength, string otherProperty, object value)
: base(maximumLength)
{
OtherProperty = otherProperty;
OtherPropertyValue = value;
}
protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
PropertyInfo property = validationContext.ObjectType.GetProperty(this.OtherProperty);
if (property == null)
{
return new ValidationResult(this.OtherProperty + " not found");
}
// Get
object actualOtherPropertyValue = property.GetValue(validationContext.ObjectInstance, null);
// If the other property matches the expected value then validate as normal
if (object.Equals(OtherPropertyValue, actualOtherPropertyValue))
{
// Call base and validate required as normal
return base.IsValid(value, validationContext);
}
return null;
}
}
}
Example Usage:
public class MyModel
{
[RequiredIf("IsBack", false)]
public string Name { get; set; }
public bool IsBack { get; set; }
}