How to change 'data-val-number' message validation in MVC while it is generated by @Html helper

Question

Assume this model:

Public Class Detail
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Answer 1

This is not gonna be easy. The default message is stored as an embedded resource into the System.Web.Mvc assembly and the method that is fetching is a private static method of an internal sealed inner class (System.Web.Mvc.ClientDataTypeModelValidatorProvider+NumericModelValidator.MakeErrorString). It's as if the guy at Microsoft coding this was hiding a top secret :-)

You may take a look at the following blog post which describes a possible solution. You basically need to replace the existing ClientDataTypeModelValidatorProvider with a custom one.

If you don't like the hardcore coding that you will need to do you could also replace this integer value inside your view model with a string and have a custom validation attribute on it which would do the parsing and provide a custom error message (which could even be localized).