There are certain properties in my application that I need to set dynamically whether they are required or not, therefore I can not use the [Required] atribute of Data Annotations.
Maybe this is not the best way to achieve what I want. So I will accept glady anny suggestions in that regard.
I have overridden the DataAnnotationsModelMetadataProvider with:
public class DynamicFieldsMetadataProvider : DataAnnotationsModelMetadataProvider
{
public override IEnumerable<ModelMetadata> GetMetadataForProperties(object container, Type containerType)
{
if (containerType == null)
throw new ArgumentNullException("containerType");
if (!typeof(DynamicFieldDataItem).IsAssignableFrom(containerType))
foreach (var metadataProperty in base.GetMetadataForProperties(container, containerType))
yield return metadataProperty;
else
foreach (var metadataProperty in base.GetMetadataForProperties(container, containerType))
{
var dynamicField = (DynamicFieldDataItem)container;
if (metadataProperty.PropertyName == "DataFieldValue")
metadataProperty.IsRequired = dynamicField.IsRequired;
yield return metadataProperty;
}
}
}
This is just a concept test, once I make it work, I will change it to something dynamic and more object oriented, but so far, with just being able to set the MetadataModel for the property DataFieldValue to IsRequired = true I can get going.
With this I successfully set in a dynamic way the IsRequired property in true (I thought, with this would be enough!), and when I debugg in my view:
#Html.EditorFor(model=>model.DataFieldValue)
The property DataFieldValue is declared like this:
public class DynamicFieldDataItem
{
public string DataFieldValue { get; set; }
public bool IsRequired{ get; set; }
}
I can see that the Metadata, has the property IsRequired in true, but when the "DataFieldValue" is rendered the "validator" is not there, and of course the validation doesn't work.
To make sure that there wasn't a problem on the configuration of my project, I checked web.config and the inclusion of the javascripts for validation, all is properly configured. What's more, If I add the attribute Required to my property, like this:
public class DynamicFieldDataItem
{
[Required]
public string DataFieldValue { get; set; }
public bool IsRequired{ get; set; }
}
The validation works perfectly!
Can anyone give me a hint? Or tell me what i am doing wrong?
Thanks!
For validations that advanced I recommend you look at FluentValidation for MVC
http://fluentvalidation.codeplex.com/wikipage?title=mvc
you can install it into your project using NuGet, and you can create custom validation classes with it.
I believe you need both a custom ModelMetadataProvider and a custom ModelValidatorProvider for this to work. From my experience they don't seem to leverage each other and both seem to setup different validation.
Related
I'm using Blazor with MudBlazor and I have the following form on an Edit page:
<EditForm Model="BookRequestVM" OnInvalidSubmit="InvalidBookRequest" OnValidSubmit="#ValidBookRequest">
...
<MudItem xs="12" sm="4">
<MudSelect T="BookType" Label="Book Type" #bind-Value="#BookRequestVM.BookType" #bind-SelectedValues="hashBookTypes" Required="true">
#foreach (var selectItem in BookTypes)
{
<MudSelectItem Value="#selectItem">#selectItem.TypeTitle</MudSelectItem>
}
</MudSelect>
</MudItem>
</EditForm>
...
#code {
public class BookType
{
public int BookTypeId { get; set; }
public string TypeTitle { get; set; }
}
public HashSet<BookType> hashBookTypes = new HashSet<BookType>();
...
protected override async Task OnInitializedAsync()
{
BookRequestVM = await _bookService.GetBookRequest(Id); // Fetch info from database
BookTypes = _bookService.GetBookTypes().ToList(); // Get all valid dropdown values
hashBookTypes = new HashSet<BookType>(BookTypes);
}
}
Because I'm pulling in existing data (this Book Type field is required when creating a book request), there will always be a Book Type associated with this Book Request. I see that the BookTypeVM was able to pull the Book Type in from the database in the service call, and on the valid submit method, it's bound and gets saved properly. It's just when it loads in, it doesn't default to the value that was saved to the database--only the first value from the dropdown list. Any ideas on what's going on here?
Is this a multi-select? If not then why are you setting #bind-SelectedValues="hashBookTypes". hashBookTypes comes from BookTypes which is a list of all the book types. I'm no expert on MudBlazor, but it appears your setting the selected values to the full list of values. Without MultiSelection="true" then I'm guessing its setting the current value to the first value in the list.
Your code has more problems than the one MrC found. You need to be very careful with using a POCO class in a select without overriding Equals() and GetHashCode() because the select uses a HashSet internally to find out which item is selected. Also, if you want it to convert the selected BookType to string it should override ToString().
Your BookType class should look like this:
public class BookType
{
public string Title { get; set; }
public override bool Equals(object other) {
return (other as BookType)?.Title == Title;
}
public override int GetHashCode()
{
return this.Title.GetHashCode();
}
public override string ToString() => Title;
}
And here is the Select to go with it:
<MudSelect T="BookType" Label="Book Type" #bind-Value="#RequestedBookType" Required="true">
#foreach (var selectItem in BookTypes)
{
<MudSelectItem Value="#selectItem">#selectItem.Title</MudSelectItem>
}
</MudSelect>
Here is a fiddle that demonstrates your code with above changes to make it work: https://try.mudblazor.com/snippet/mOwvPvbhHYHFBoiV
#bind-SelectedValues="hashBookTypes" was the culprit. This is used for multiselect. Unfortunately, I don't recall adding this code, but removing this resolved this issue.
I have a web api 2 application, and in my controller , I have this code :
[Queryable]
public IQueryable<Title> GetTitles()
{
return db.Titles;
}
and here is the Title entity :
public partial class Title
{
public Title()
{
this.People = new HashSet<Person>();
}
public short Id { get; set; }
public string NameT { get; set; }
public virtual ICollection<Person> People { get; set; }
}
When people query the Titles, they must get only "NameT" property. but now they get all of the properties. and yes, I know about $select, but I want another way. means even they use $select, they should not able to get "Id" property for example. if I have to bring more information, please tell me. thanks.
There are two ways to solve your problem when you use ODataController. However, they won't affect ApiController non-query part.
In that condition, you can try what Zoe suggested.
1.Ignore those properties while building your model with model builder.
builder.EntityType<Title>().Ignore(title => title.Id);
2.Add ignore member attributes on those properties.
[IgnoreDataMember]
public short Id { get; set; }
More than these, we provide support for limiting the set of allowed queries in Web API 2.2 for OData v4.0.
http://blogs.msdn.com/b/webdev/archive/2014/03/13/getting-started-with-asp-net-web-api-2-2-for-odata-v4-0.aspx
We can use attributes like Unsortable, NonFilterable, NotExpandable or NotNavigable on the properties of the types in our model, or we can configure this explicitly in the model builder.
Maybe you can have filter in your action GetTitles(), like:
[Queryable]
public IQueryable<Title> GetTitles()
{
return db.Titles.Select(t=>t.Name);
}
Use the ODataModelBuilder class as opposed to the ODataConventionModelBuilder class.
var modelBuilder = new ODataModelBuilder();
var titles = modelBuilder.EntitySet<Title>("titles");
var title = titles.EntityType;
title.HasKey(x => x.Id);
title.Ignore(x => x.Id);
title.Property(x => x.TName);
titles.HasIdLink(x => { return x.GenerateSelfLink(true); }, true);
config.Routes.MapODataRoute("odata", "odata", modelBuilder.GetEdmModel());
I am using the example at The Complete Guide To Validation In ASP.NET MVC 3 to create a RequiredIf validation attribute (it's about 1/3 down the page under the heading of "A more complex custom validator"). It all works fine with the exception of one scenario, and that is if I have the need to validate against a complex type. For example, I have the following model:
public class MemberDetailModel
{
public int MemberId { get; set; }
// Other model properties here
public MemberAddressModel HomeAddress { get; set; }
public MemberAddressModel WorkAddress { get; set; }
}
public class MemberAddressModel
{
public bool DontUse { get; set; }
// Other model properties here
[RequiredIf("DontUse", Comparison.IsEqualTo, false)]
public string StreetAddress1 { get; set; }
}
The problem is that when the attribute validation for the StreetAddress property is rendered, it get's decorated with the attribute of data-val-requiredif-other="DontUse". Unfortunately, since the address is a sub-type of the main model, it needs to be decorated with a name of HomeAddress_DontUse and not just DontUse.
Strangely enough, the validation works fine for server-side validation, but client-side unobtrusive validation fails with an JS error because JS can't find the object with a name of just "DontUse".
Therefore, I need to find a way to change the ModelClientValidationRequiredIfRule method to know that the property it is validating is a sub-type of a parent type, and if so, prepend the ParentType_ to the "otherProperty" field (e.g. otherProperty becomes HomeAddress_DontUse.
I have tried passing in typeof(MemberAddressModel) as a parameter of the attribute, but even when debugging the attribute creation, I can't seem to find any reference to the parent type of HomeAddress or WorkAddress from that type.
Based on the suggestion from The Flower Guy, I was able to come up with the following which seems to work. I simply modified the following in the customValidation.js file:
jQuery.validator.addMethod("requiredif", function (value, element, params) {
if ($(element).val() != '') return true;
var prefix = getModelPrefix(element.name); // NEW LINE
var $other = $('#' + prefix + params.other); // MODIFIED LINE
var otherVal = ($other.attr('type').toUpperCase() == "CHECKBOX") ? ($other.attr("checked") ? "true" : "false") : $other.val();
return params.comp == 'isequalto' ? (otherVal != params.value) : (otherVal == params.value);
});
I also added the following method to that file (within the JQuery block so as to be only privately accessible):
function getModelPrefix(fieldName) {
return fieldName.substr(0, fieldName.lastIndexOf(".") + 1).replace(".","_");
}
Cannot do it exactly right now, but the problem is in the client javascript function:
jQuery.validator.addMethod("requiredif" ...
The js is not sophisticated enough to cope with complex view models where there may be a model prefix. If you take a look at Microsoft's jquery.validate.unobstrusive.js (in the Scripts folder over every MVC3 application), you will find some useful methods including getModelPrefix and appendModelPrefix. You can take a similar approach and change the requiredIf validation method - take a look at the equalto method in jquery.validate.unobstrusive.js for a helping hand.
MVC 3, EntityFramework 4.1, Database First, Razor customization:
I have an old database that sometimes uses Int16 or Char types for a field that must appear as a CheckBox in the MVC _CreateOrEdit.cshtml View. If it is an Int, 1=true and 0=false. If it is a Char, "Y"=true and "N"=false. This is too much for the Entity Framework to convert automatically. For the Details View, I can use:
#Html.CheckBox("SampleChkInt", Model.SampleChkInt==1?true:false)
But this won't work in place of EditorFor in the _CreateOrEdit.cshtml View.
How to do this? I was thinking of a custom HtmlHelper, but the examples I've found don't show me how to tell EntityFramework to update the database properly. There are still other such customizations that I might like to do, where the MVC View does not match the database cleanly enough for EntityFramework to do an update. Answering this question would be a good example. I am working on a sample project, using the following automatically generated (so I can't make changes to it) model class:
namespace AaWeb.Models
{
using System;
using System.Collections.Generic;
public partial class Sample
{
public int SampleId { get; set; }
public Nullable<bool> SampleChkBit { get; set; }
public Nullable<short> SampleChkInt { get; set; }
public Nullable<System.DateTime> SampleDate { get; set; }
public string SampleHtml { get; set; }
public Nullable<int> SampleInt { get; set; }
public Nullable<short> SampleYesNo { get; set; }
public string Title { get; set; }
public byte[] ConcurrencyToken { get; set; }
}
}
I figured it out. Do not need a model binder or Html Helper extension:
In _CreateOrEdit.cshtml, I made up a new name SampleChkIntBool for the checkbox, and set it according to the value of the model SampleChkInt:
#Html.CheckBox("SampleChkIntBool", Model == null ? false : ( Model.SampleChkInt == 1 ? true : false ), new { #value = "true" })
Then, in the [HttpPost] Create and Edit methods of the Sample.Controller, I use Request["SampleChkIntBool"] to get the value of SampleChkIntBool and use it to set the model SampleChkInt before saving:
string value = Request["SampleChkIntBool"];
// #Html.CheckBox always generates a hidden field of same name and value false after checkbox,
// so that something is always returned, even if the checkbox is not checked.
// Because of this, the returned string is "true,false" if checked, and I only look at the first value.
if (value.Substring(0, 4) == "true") { sample.SampleChkInt = 1; } else { sample.SampleChkInt = 0; }
I believe a custom model binder would be in order here to handle the various mappings to your model.
ASP.NET MVC Model Binder for Generic Type
etc
etc
Here is the way to go from checkbox to database, without the special code in the controller:
// The following statement added to the Application_Start method of Global.asax.cs is what makes this class apply to a specific entity:
// ModelBinders.Binders.Add(typeof(AaWeb.Models.Sample), new AaWeb.Models.SampleBinder());
// There are two ways to do this, choose one:
// 1. Declare a class that extends IModelBinder, and supply all values of the entity (a big bother).
// 2. Declare a class extending DefaultModelBinder, and check for and supply only the exceptions (much better).
// This must supply all values of the entity:
//public class SampleBinder : IModelBinder
//{
// public object BindModel(ControllerContext cc, ModelBindingContext mbc)
// {
// Sample samp = new Sample();
// samp.SampleId = System.Convert.ToInt32(cc.HttpContext.Request.Form["SampleId"]);
// // Continue to specify all of the rest of the values of the Sample entity from the form, as done in the above statement.
// // ...
// return samp;
// }
//}
// This must check the property names and supply appropriate values from the FormCollection.
// The base.BindProperty must be executed at the end, to make sure everything not specified is take care of.
public class SampleBinder : DefaultModelBinder
{
protected override void BindProperty( ControllerContext cc, ModelBindingContext mbc, System.ComponentModel.PropertyDescriptor pd)
{
if (pd.Name == "SampleChkInt")
{
// This converts the "true" or "false" of a checkbox to an integer 1 or 0 for the database.
pd.SetValue(mbc.Model, (Nullable<Int16>)(cc.HttpContext.Request.Form["SampleChkIntBool"].Substring(0, 4) == "true" ? 1 : 0));
// To do the same in the reverse direction, from database to view, use pd.GetValue(Sample object).
return;
}
// Need the following to get all of the values not specified in this BindProperty method:
base.BindProperty(cc, mbc, pd);
}
}
All examples that I can find do something like this:
[Required]
public string Title { get; set; }
That's great for simple cases, but what about something that checks the database or something else server side?
For example, say I have a movie database and I want to allow people to rate it. How could I tell if someone has already rated a movie, as I'd only want them to rate a movie once.
I would think it would be something like:
public IEnumerable<string> ValidateUserHasNotAlreadyRatedMovie(User currentUser, Guid movieId)
{
if(movieHasAlreadyBeenRated)
{
yield return "Movie been rated man!";
}
}
Now then I'd call this with something like:
var errors = new List<string>();
errors.AddRange(ValidateUserHasNotAlreadyRatedMovie(topic, comment));
if(errors.Any())
{
throw new SomeTypeOfCustomExtension??(errors);
}
Do I just need to extend Exception for a custom SomeTypeOfCustomExtension above, or is there something already built? Am I doing this the ASP.NET MVC 2 way?
After that how do I put it into the model state and let the view know something's wrong?
See this it may help
Remote Validation with ASP.NET MVC 2
http://bradwilson.typepad.com/blog/2010/01/remote-validation-with-aspnet-mvc-2.html
The ASP.NET 2.0 MVC way of doing custom validation is described here. It basically shows how to write a custom validation attribute. Here is an example of one such custom attribute that checks the database for name uniqueness:
public class UniqueNameAttribute : ValidationAttribute
{
public override bool IsValid(object value)
{
string str = (string)value;
if (String.IsNullOrEmpty(str))
return true;
using (XDataContext vt = new XDataContext())
{
return !(vt.Users.Where(x => x.Username.Equals(str)).Any());
}
}
}
The ASP.NET 1.0 way (that doesn't require custom attributes) is described here.