7/22/2023 0 Comments Mvc data annotations if equalFinally, we converted the value to DateTime and compared it with current date and if the value is greater than today’s date we return a validation failure with a = "Create" It is generally a good idea to only validate if the property has a value, so we add a null check and return ValidationResult.Success if the value is null. This is done by overriding the IsValid method. The next thing we need to do is actually implement the validation logic. Here, the ValidBirthDate attribute is only permitted on properties and only a single instance of the attribute may appear on each property. The class is decorated with an AttributeUsage attribute that tell. Our custom validator subclasses the built-in abstract class ValidationAttribute. Return new ValidationResult("Birth date can not be greater than current date.") Protected override ValidationResult IsValid(object value, ValidationContext validationContext)ĭateTime _birthJoin = Convert.ToDateTime(value) Public sealed class ValidBirthDate : ValidationAttribute Namespace CustomValidationAttributeDemo.ValidationAttributes These attributes perform all the magical stuff for us and create both server and client side validation code automatically. The above model class is using a bunch of built in attributes along with our custom validation attribute ValidBirthDate. Namespace CustomValidationAttributeDemo.Models Using CustomValidationAttributeDemo.ValidationAttributes Let’s begin by creating a new ASP.NET MVC project called CustomValidationAttributeDemo and then create a simple model called Customer. Getting Startedįor the sake of this tutorial, I’ve decided to implemeant a ValidBirthDate attribute that force user to enter a birth date which is less than the current date. It sounds like a lot of work but I assure you once you get started you will find it relatively straightforward. Finally, we create an adapter to transform the HTML5 attributes into a format that our custom function can understand. Thirdly, we write a custom javascript function that performs validation on the client. Next we implement IClientValidatable on our attribute to allow HTML5 data-* attributes to be passed to the client. ![]() First we subclass ValidationAttribute and add our server side validation logic. There are four distinct parts to creating a fully functional custom validator that works on both the client and the server.
0 Comments
Leave a Reply. |