MVC 5 - change Data anotation error message for Integers - asp.net-mvc

In my Mvc5 test project I have a model with a property like the following:
[Required]
[DisplayName("Codigo Cliente")]
public int ClientCode{ get; set; }
the default error message when the user enteres a letter of special character in the editor is:
The field Codigo Cliente must be a number.
How can I modify this? in this case I need to change the language, but in case that I wanted to show a more specific error what can I do?
I have tried with the DataType attribute but the Enum does not have a value that applys for this case (numbers)

Use Range:
http://msdn.microsoft.com/en-us/library/system.componentmodel.dataannotations.rangeattribute.aspx
Or use IntegerOnly from Data Annotations Extensions
http://dataannotationsextensions.org/Integer/Create

The simplest way I found to solve this issue is use String with Range attribute in Data Annotation Model like specify below.
[Required]
[Range(0, int.MaxValue, ErrorMessage = "Codigo Cliente must be a positive or negative non-decimal number.")]
[DisplayName("Codigo Cliente")]
public string ClientCode { get; set; }
In Range attribute you can specify your custom Error Message.
For Interger use int.MaxValue , For double use double.MaxValue like so on.
I hope this will help you a lot.

If you want to specify a message you must use this
[Required(ErrorMessage = "your message")]
If you want to use a lang. based message is not that easy. You can use multiple resource file (for every language you need) and try a custom error binder that extends the DefaultModelBinder and make an override of the method BindModel(), there you can make your custom validation ad use your custom language message.

Related

Setting MaxLength gives you error

Following is one of the property in my MVC model.
[Display(Name = "Event ID")]
[MaxLength(8, ErrorMessage = "Event ID can be of maximum 8 characters long")]
[Required(ErrorMessage="Event ID must be entered")]
public Nullable<int> ID_EVENTO { get; set; }
I have bound the model with a View, and when I try to click "Submit" button, it gives following runtime error -
Unable to cast object of type 'System.Int32' to type 'System.Array'
While, if I remove the "MaxLength" attribute, it starts working.
What could be the issue here?
MaxLength is used to specify the maximum length of array or string data allowed in a property.
Your ID_EVENTO is a nullable int (rather than array or string), that's why the attribute doesn't work. Sounds like you either want to remove the attribute or use a different one - Range or something?

How to validate that user enters string in textbox in asp mvc4

How to validate that user enters string in textbox in asp mvc4?
What to write in required tag?
[required]
Use the [RegularExpression] attribute if you want to limit the user to only typing in alphabetic characters.
More info on MSDN.
Here is a good link to a regular expression that you can use.
This example maybe helps:
public class CustomerMetaData
{
// Require that the Title is not null.
// Use custom validation error.
[Required(ErrorMessage = "Title is required.")]
public object Title;
// Require that the MiddleName is not null.
// Use standard validation error.
[Required()]
public object MiddleName;
}
There are many ways to do it
1) By using plain Javascript or JQuery to check if it has value before submiting the page
2) On controller method check if it has value
3) If you a using EF and your view binded to a model add attribute called [Required]to the property of that model.
What do you actually want to do?
Make sure that the object the server receives has correct data in it? Then you should use data attributes on your C# model. However what do you mean by "enters string"? If the user simply needs to enter any string, then [Required] works - this just means that there has to be some value entered. Do you only want to allow a specific set of characters, like the English alphabet? Then you need to use a RegularExpression attribute.
If you further specify what you actually want to do I am sure we can help you more.

asp.net mvc 3 validation on data type

I am trying to realize valition on data type. I have used DataAnnotations, but for data type it's not showing customized message
for example when I' am trying enter string data into int typed field. How I can customize messages in this case?
If I had to guess, you sound like you want a custom message to display when validating one or more fields in your model. You can subclass the DataAnnotations.ValidationAttribute class and override the IsValid(object) method and finally setting a custom ErrorMessage value (where ErrorMessage already belongs to the ValidationAttribute class)
public class SuperDuperValidator : ValidationAttribute
{
public override bool IsValid(object value)
{
bool valid = false;
// do your validation logic here
return valid;
}
}
Finally, decorate your model property with the attribute
public class MyClass
{
[SuperDuperValidator(ErrorMessage="Something is wrong with MyInt")]
public int MyInt { get; set; }
}
If you're using out-of-the-box MVC3, this should be all you need to propertly validate a model (though your model will probably differ/have more properties, etc) So, in your [HttpPost] controller action, MVC will automagically bind MyClass and you will be able to use ModelState.IsValid to determine whether or not the posted data is, in fact, valid.
Pavel,
The DataAnnotations DataType attribute does not affect validation. It's used to decide how your input is rendered. In such a case, David's solution above works.
However, if you want to use only the built-in validation attributes, you probably need to use the Range attribute like this:
[Range(0, 10, ErrorMessage="Please enter a number between 0 and 10")]
public int MyInt { get ; set ;}
(Of course, you should really be using the ErrorMessageResourceName/Type parameters and extract out hard-coded error message strings into resx files.)
Make sure to let MVC know where to render your error message:
<%= Html.ValidationMessageFor(m => m.MyInt) %>
Or you can just use EditorForModel and it will set it up correctly.
I don't think this has been answered because I have the same issue.
If you have a Model with a property of type int and the user types in a string of "asd" then the MVC3 framework binding/validation steps in and results in your view displaying "The value 'asd' is not valid for <model property name or DisplayName here>".
To me the poster is asking can this message that the MVC3 framework is outputting be customized?
I'd like to know too. Whilst the message is not too bad if you label your field something that easily indicates an number is expected you might still want to include additional reasons so it says something like:
"The value 'asd' is not valid for <fieldname>; must be a positive whole number."
So that the user is not entering value after value and getting different error messages each time.

Change the default error message for data type in mvc3

I'm developing in mvc 3 and have a little question.
I want to change the default error message for invalid data type.
let say I've a model with the prop Price, and I want his error message for input "aaa" will be "The only value you can enter here is a number".
what is the easiest way of doing that?
(I want to do it for all of my models)
You could use a Regular Expression data annotation on your model property, e.g.:
[RegularExpression(#"^[0-9\.]*$", ErrorMessage="The only value you can enter here is a number")]
public double Price { get; set; }
You should approach validation from a white list point of view - i.e. what should be allowed through, as opposed to a black list, which would be what is invalid.
More information here:
http://www.asp.net/mvc/tutorials/mvc-music-store-part-6
Hope this helps!
Sam
http://haacked.com/archive/2011/03/19/fixing-binding-to-decimals.aspx
Assuming that you are working with entity framework or Linq to SQL and your class name is Product. here is the example for that. create a partial class like below;
[MetadataType(typeof(Product.MetaData))]
public partial class Product {
private class MetaData {
[Required(ErrorMessage = "The only value you can enter here is a number")]
public decimal Price { get; set; }
}
}
you should add the following using statement in order to use dataanotations for validation;
using System.ComponentModel.DataAnnotations;

change validate message in data annotation

my object has field with data type int. when i put in html form in this textbox letter not number the validator say- The field must be a number. how can i change this messages like this
[Required(ErrorMessage = "Введите название")]
[DisplayName("Название")]
public int age { get; set; }
I haven't found a clean way to achieve this using Data Annotations. One way would be to write a custom model binder but this seems like a lot of work to do for such a simple task.
Another way to achieve this is to add an App_GlobalResources folder to your ASP.NET application. Add a resource file called Messages.resx containing a PropertyValueRequired string resource.
PropertyValueRequired = "Some custom error message"
In your Application_Start register the resource class key:
protected void Application_Start()
{
RegisterRoutes(RouteTable.Routes);
DefaultModelBinder.ResourceClassKey = "Messages";
}
Note that ASP.NET MVC 2 uses the PropertyValueInvalid instead of PropertyValueRequired resource key.
IMO using Data Annotations to perform validation logic is limited (maybe in .NET 4 this will change). If you want to have full control over the validation logic I would recommend you using a validation library such as Fluent Validation or xVal.
I ran into the same problem and worked around it by specifying a RegularExpression that only allows positive natural numbers.
[Required(ErrorMessage = "Введите название")]
[DisplayName("Название")]
[RegularExpression(#"^[0-9]+$", ErrorMessage = "Поле возраст не является числом")]
public int age { get; set; }
Not sure if there are any downfalls to this solution. It seems to work fine for me.
PS: If you don't want to allow leading zeroes use "^[1-9]+[0-9]*$".
In retrospect: I have to admit though it's a bit weird to add a regular expression to an integer.

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