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Custom Property name for FromUrl Model

I have a model which is used to bind QueryString, that follows the naming conversation of c# but the QueryString is in a different naming conversation. How to provide a custom property name for model properties that are assigned vis FromUrl?
// Will NOT work
public class FormatDatabaseRequest
{
[JsonProperty("_type")]
public string Type { get; set; }
[JsonProperty(Name = "awef_flag")]
public string AwefFlag { get; set; }
}
// Controller.cs
[HttpPost]
public async Task<HttpResponseMessage> FormatDatabaseAsync([FromUri] FormatDatabaseRequest request) {}
// Sample URL (QueryString MUST be named _type and awef_flag)
// https://localhost:43521/myControllerName?_type=asdfa&awef_flag=asdf

If you want to get fields from URL like that, I recommend using [FromQuery] attribute, like so:
public async Task<HttpResponseMessage> Get([FromQuery] FormatDatabaseRequest data)
Then, such URL
https://localhost:43521/myControllerName?type=asdfa&awefflag=asdf
Will be parsed correctly to your object :)

json has nothing to do with query string. I don't understand why you don't like underscore properties, but you can hide them like this
public class FormatBaseRequest
{
public string _Type { get; set; }
public string Awef_flag{ get; set; }
}
public class FormatDatabaseRequest:FormatBaseRequest
{
public string Type
{
get { return _Type; }
set { _Type=value ; } //or leave just get
}
public string AwefFlag
{
get { return Awef_flag; }
set { Awef_flag=value ; } //or leave just get
}
}
you can use it for query string and for c#

How can I get field value via reflection if name is different with field name

I have a class
[BsonIgnoreExtraElements]
public class CustomerModel
{
public string BranchID { get; set; }
public string BranchName { get; set; }
public string ReceiverID { get; set; }
public string ReceiverName{ get; set; }
}
I am writing a filter activity which can validate any field with specific value configured in MongoDB
"Exclude":[{"SourceCol":"Receiver Mode ID","Values":{"Value":["G","8","J"]}}
and written the comparing logic as
public static object GetPropValue(object src, string propName)
{
return src.GetType().GetProperty(propName).GetValue(src, null);
}
public static bool CheckPropertyCompare(CustomerModel customer, Exclude item)
{
var propertyValue = GetPropValue(customer, item.SourceCol);
return item.Values.Value.ToList().Contains(propertyValue);
}
In this, the Receiver Mode ID from MongoDB is actually looking for ReceiverID and I am stuck as to how can I resolve this issue. The only option I can think of is Key-Value pair collection to fetch the field name. but would like to know if there is any options like Attributes which can ease this process.
TIA

I think you can achieve that with Attributes as you say.
You can create a custom attribute, like this:
internal class MongoDBFieldAttribute : Attribute
{
public string Field{ get; private set; }
public MongoDBFieldAttribute(string field)
{
this.Field= field;
}
}
Then in your class:
public class CustomerModel
{
...
[MongoDBField("ReceiverModeID")]
public string ReceiverID { get; set; }
}
I think it could be better without spaces, it could be a problem, maybe yo can use a Trim() or similar... or yoy can try [MongoDBField("Receiver Mode ID")], never tried.
Then you can create a method than can relation both, property name and attribute name, for example:
private Dictionary<string, string> getRelationPropertyAttribute(Type type)
{
var dicRelation = new Dictionary<string, string>();
var properties = type.GetProperties();
foreach (var property in properties)
{
var attributes = property.GetCustomAttributes(inherit: false);
var customAttributes = attributes
.AsEnumerable()
.Where(a => a.GetType() == typeof(MongoDBFieldAttribute));
if (customAttributes.Count() <= 0)
continue;
foreach (var attribute in customAttributes)
{
if (attribute is MongoDBFieldAttribute attr)
dicRelation[attr.Field] = property.Name;
}
}
return dicRelation;
}
Finally, you can play with that dictionary and in your method you can do something like that:
public static bool CheckPropertyCompare(CustomerModel customer, Exclude item)
{
var dicRelation = getRelationPropertyAttribute(typeof(CustomerModel));
var propertyName = dicRelation[item.SourceCol];
var propertyValue = GetPropValue(customer, propertyName);
return item.Values.Value.ToList().Contains(propertyValue);
}
It´s an idea...
Hope it helps.

Strict mapping in web Web API (Over-Posting)

I just realized that the mapping between the JSON send from a query and my API is not strict.
I give you more explanations:
Here is my C# POCO
public partial class AddressDto
{
public string AddrId { get; set; }
public string Addr1 { get; set; }
public string Addr2 { get; set; }
public string PostalCode { get; set; }
public string City { get; set; }
public string Country { get; set; }
}
And the REST JSON query
PUT http://Localhost:55328/api/ClientAddr/ADD-2059-S002 HTTP/1.1
content-type: application/json
{
"AddrID": "ADD-2059-S002",
"addr1": "B-1/327",
"addr2": "1ST FLOOR",
"city": "Paris",
"Zip_Code": "78956",
"country": "France",
}
The web client send a PUT with Zip_Code in place of PostalCode. PostalCode is not madatory/required. But Zip_Code does not exist in my DTO.
So in my C# code testing the model state won't help.
public HttpResponseMessage Put(string id, AddressDto address)
{
if (!ModelState.IsValid)
return BadRequest(ModelState); // This wont help
}
How can I raise exception when the client is using something in the JSON that is not existing in my DTO (model) ?

if you need to identify extra columns and handle that as an error you have to extend IModelBinder interface and tell json deserializer to treat extra column as an error and add that error to ModelState. By that way you can check in controller for ModelState.IsValid. Checkout the below Code
CustomModelBinder
public class CustomModelBinder : IModelBinder
{
public bool BindModel(HttpActionContext actionContext, ModelBindingContext bindingContext)
{
JsonSerializerSettings settings = new JsonSerializerSettings();
settings.MissingMemberHandling = MissingMemberHandling.Error;
ObjToPass obj = new ObjToPass();
;
try
{
ObjToPass s =
JsonConvert.DeserializeObject<ObjToPass>(actionContext.Request.Content.ReadAsStringAsync().Result,
settings);
bindingContext.Model = obj;
}
catch (Exception ex)
{
bindingContext.ModelState.AddModelError("extraColumn", ex.Message);
}
return true;
}
}
public class CustomerOrderModelBinderProvider : ModelBinderProvider
{
public override IModelBinder GetBinder(System.Web.Http.HttpConfiguration configuration, Type modelType)
{
return new CustomModelBinder();
}
}
Object Class that is passed to webapi
public class ObjToPass
{
public int Id { get; set; }
public string Name { get; set; }
}
Controller
[HttpPost]
public void PostValues([ModelBinder(typeof(CustomerOrderModelBinderProvider))] ObjToPass obj)
{
if(!ModelState.IsValid)
{ }
else
{
}
}
This sample holds good for HttpPut as well.

"Over-Posting": A client can also send more data than you expected. For example:
Here, the JSON includes a property ("Zip_Code") that does not exist in the Address model. In this case, the JSON formatter simply ignores this value. (The XML formatter does the same.)
https://learn.microsoft.com/en-us/aspnet/web-api/overview/formats-and-model-binding/model-validation-in-aspnet-web-api

Using Reflection and GetValue problems

I have an abstract class that looks like so:
public abstract class PageObjectsBase
{
public abstract string FriendlyName { get; }
public abstract string PageObjectKeyPrefix { get; }
public abstract string CollectionProperty { get; }
}
And a class that derives from PageObjectsBase:
public class PageRatingList : PageObjectsBase
{
public IList<PageRating> PageRatings { get; set; }
public PageRatingList()
{
this.PageRatings = new List<PageRating>();
}
public override string CollectionProperty
{
get
{
var collectionProperty = typeof(PageRatingList).GetProperties().FirstOrDefault(p => p.Name == "PageRatings");
return (collectionProperty != null) ? collectionProperty.Name : string.Empty;
}
}
public override string FriendlyName
{
get
{
return "Page feedback/rating";
}
}
public override string PageObjectKeyPrefix
{
get
{
return "pagerating-";
}
}
}
And a PageRating class which PageRatingList.PageRatings is holding a collection of:
public class PageRating : PageObjectBase
{
public int Score { get; set; }
public string Comment { get; set; }
public string Name { get; set; }
public string Email { get; set; }
}
The PageRatingList is being stored in a database (EPiServer's Dynamic Data Store, more specifically using the Page Object Manager). I need to create some reporting functionality and am essentially loading all reports that derive from PageObjectBase. When it comes to returning the data, the code will never know at compile time what type of data it is to load, so I am using Reflection. In my reporting class I have:
//this gives me the right type
var type = Type.GetType("MyNameSpace.PageRatingList", true);
var startPageData = this._contentRepository.Get<PageData>(startPage);
PageObjectManager pageObjectManager = new PageObjectManager(startPageData);
//this loads the instances from the DB
var props = pageObjectManager.LoadAllMetaObjects()
.FirstOrDefault(o => o.StoreName == "Sigma.CitizensAdvice.Web.Business.CustomEntity.PageRatingList");
//this gives me 4 PropertyInfo objects (IList: PageRatings, string : CollectionProperty, string :FriendlyName, string : PageObjectKeyPrefix)
var properties = props.Value.GetType().GetProperties();
I can then iterate through the PropertyInfo objects using:
foreach (var property in properties)
{
//extract property value here
}
The issue I am having is that I cannot figure out how to get the value of each of the propertyinfo objects. In addition, one of those properties is type List and again we wont know the type of T until runtime. So I also need some logic that checks if one of the PropertyInfo objects is of type List and then provides access to each of the properties in the List - the List being of type PageRating.
Can anyone help here? I've not really used reflection in the past so I am winging my way through it, rightly or wrongly!
Many thanks
Al

I may be missunderstanding the problem, but i think you may use something like this:
var props = new PageRatingList(); /*actual instanse of the object, in your case, i think "props.Value" */
var properties = typeof(PageRatingList).GetProperties();
foreach (var property in properties)
{
if (property.PropertyType == typeof(IList<PageRating>))
{
IList<PageRating> list = (IList<PageRating>)property.GetValue(props);
/* do */
}
else
{
object val = property.GetValue(props);
}
}
Hope this helps to find your solution.

DataAnnotations "NotRequired" attribute

I've a model kind of complicated.
I have my UserViewModel which has several properties and two of them are HomePhone and WorkPhone. Both of type PhoneViewModel. In PhoneViewModel I have CountryCode, AreaCode and Number all strings. I want to make the CountryCode optional but AreaCode and Number mandatory.
This works great. My problem is that in the UserViewModel WorkPhone is mandatory, and HomePhone is not.
Is there anyway I can dissable Require attributs in PhoneViewModel by setting any attributes in HomeWork property?
I've tried this:
[ValidateInput(false)]
but it is only for classes and methods.
Code:
public class UserViewModel
{
[Required]
public string Name { get; set; }
public PhoneViewModel HomePhone { get; set; }
[Required]
public PhoneViewModel WorkPhone { get; set; }
}
public class PhoneViewModel
{
public string CountryCode { get; set; }
public string AreaCode { get; set; }
[Required]
public string Number { get; set; }
}

[UPDATED on 5/24/2012 to make the idea more clear]
I'm not sure this is the right approach but I think you can extend the concept and can create a more generic / reusable approach.
In ASP.NET MVC the validation happens at the binding stage. When you are posting a form to the server the DefaultModelBinder is the one that creates model instances from the request information and add the validation errors to the ModelStateDictionary.
In your case, as long as the binding happens with the HomePhone the validations will fire up and I think we can't do much about this by creating custom validation attributes or similar kind.
All I'm thinking is not to create model instance at all for HomePhone property when there are no values available in the form (the areacode, countrycode and number or empty), when we control the binding we control the validation, for that, we have to create a custom model binder.
In the custom model binder we are checking if the property is HomePhone and if the form contains any values for it's properties and if not we don't bind the property and the validations won't happen for HomePhone. Simply, the value of HomePhone will be null in the UserViewModel.
public class CustomModelBinder : DefaultModelBinder
{
protected override void BindProperty(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor)
{
if (propertyDescriptor.Name == "HomePhone")
{
var form = controllerContext.HttpContext.Request.Form;
var countryCode = form["HomePhone.CountryCode"];
var areaCode = form["HomePhone.AreaCode"];
var number = form["HomePhone.Number"];
if (string.IsNullOrEmpty(countryCode) && string.IsNullOrEmpty(areaCode) && string.IsNullOrEmpty(number))
return;
}
base.BindProperty(controllerContext, bindingContext, propertyDescriptor);
}
}
Finally you have to register the custom model binder in global.asax.cs.
ModelBinders.Binders.Add(typeof(UserViewModel), new CustomModelBinder());
So now of you have an action that takes UserViewModel as parameter,
[HttpPost]
public Action Post(UserViewModel userViewModel)
{
}
Our custom model binder come into play and of form doesn't post any values for the areacode, countrycode and number for HomePhone, there won't be any validation errors and the userViewModel.HomePhone is null. If the form posts atleast any one of the value for those properties then the validation will happen for HomePhone as expected.

I've been using this amazing nuget that does dynamic annotations: ExpressiveAnnotations
It allows you to do things that weren't possible before such as
[AssertThat("ReturnDate >= Today()")]
public DateTime? ReturnDate { get; set; }
or even
public bool GoAbroad { get; set; }
[RequiredIf("GoAbroad == true")]
public string PassportNumber { get; set; }
Update: Compile annotations in a unit test to ensure no errors exist
As mentioned by #diego this might be intimidating to write code in a string, but the following is what I use to Unit Test all validations looking for compilation errors.
namespace UnitTest
{
public static class ExpressiveAnnotationTestHelpers
{
public static IEnumerable<ExpressiveAttribute> CompileExpressiveAttributes(this Type type)
{
var properties = type.GetProperties()
.Where(p => Attribute.IsDefined(p, typeof(ExpressiveAttribute)));
var attributes = new List<ExpressiveAttribute>();
foreach (var prop in properties)
{
var attribs = prop.GetCustomAttributes<ExpressiveAttribute>().ToList();
attribs.ForEach(x => x.Compile(prop.DeclaringType));
attributes.AddRange(attribs);
}
return attributes;
}
}
[TestClass]
public class ExpressiveAnnotationTests
{
[TestMethod]
public void CompileAnnotationsTest()
{
// ... or for all assemblies within current domain:
var compiled = Assembly.Load("NamespaceOfEntitiesWithExpressiveAnnotations").GetTypes()
.SelectMany(t => t.CompileExpressiveAttributes()).ToList();
Console.WriteLine($"Total entities using Expressive Annotations: {compiled.Count}");
foreach (var compileItem in compiled)
{
Console.WriteLine($"Expression: {compileItem.Expression}");
}
Assert.IsTrue(compiled.Count > 0);
}
}
}

I wouldn't go with the modelBinder; I'd use a custom ValidationAttribute:
public class UserViewModel
{
[Required]
public string Name { get; set; }
public HomePhoneViewModel HomePhone { get; set; }
public WorkPhoneViewModel WorkPhone { get; set; }
}
public class HomePhoneViewModel : PhoneViewModel
{
}
public class WorkPhoneViewModel : PhoneViewModel
{
}
public class PhoneViewModel
{
public string CountryCode { get; set; }
public string AreaCode { get; set; }
[CustomRequiredPhone]
public string Number { get; set; }
}
And then:
[AttributeUsage(AttributeTargets.Property]
public class CustomRequiredPhone : ValidationAttribute
{
protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
ValidationResult validationResult = null;
// Check if Model is WorkphoneViewModel, if so, activate validation
if (validationContext.ObjectInstance.GetType() == typeof(WorkPhoneViewModel)
&& string.IsNullOrWhiteSpace((string)value) == true)
{
this.ErrorMessage = "Phone is required";
validationResult = new ValidationResult(this.ErrorMessage);
}
else
{
validationResult = ValidationResult.Success;
}
return validationResult;
}
}
If it is not clear, I'll provide an explanation but I think it's pretty self-explanatory.

Just some observation: the following code couse a problem if the binding is more than simple filed. I you have a case that in object have nested object it going to skip it and caouse that some filed not been binded in nested object.
Possible solution is
protected override void BindProperty(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor)
{
if (!propertyDescriptor.Attributes.OfType<RequiredAttribute>().Any())
{
var form = controllerContext.HttpContext.Request.Form;
if (form.AllKeys.Where(k => k.StartsWith(string.Format(propertyDescriptor.Name, "."))).Count() > 0)
{
if (form.AllKeys.Where(k => k.StartsWith(string.Format(propertyDescriptor.Name, "."))).All(
k => string.IsNullOrWhiteSpace(form[k])))
return;
}
}
base.BindProperty(controllerContext, bindingContext, propertyDescriptor);
}
much thanks to Altaf Khatri