Custom Validators in ASP.NET Development - Clean vs Efficient

I'm working on a page that has a significant number of textboxes/dropdowns/etc to fill out. The majority of these are going to be performing some sort of custom validation. I should note that it's nothing of substantial size - all just string or integer values.

I always hear (and have typically always agreed) that as much validation should be performed on the client rather than on the server, but in this case I am unsure. The difference here is that this project will be passed on to an IT guy who knows about computers but is still new to programming - he will be the one in charge of making the minor updates and changes to the way these custom validations work in the future.

My idea shifted from being as efficient as possible to being a bit less efficient but much more readable. I created a new class specifically for all of my validations which will be used throughout the website. By forcing all of my custom validation code in this class, though, I eliminate any client-side validations I might be able to perform. I should also note that each page that requires a custom validation will generally need to perform at least one server-side validation, so I will never be able to use client-side 100%

Considering the relatively low level of activity on the website (currently and in the future), would you consider this as an acceptable solution? Or would you ALWAYS prefer to have as much validation on the client as possible in order to increase the responsiveness, even if it makes things a bit more messy for whoever may be wo开发者_StackOverflow社区rking on it in the future?

The benefit of client-side validation is that the user doesn't have to wait for a page to postback.

Validation constraints are best declared server-side. Otherwise, someone could disable JavaScript on their browser and send corrupt data to your database.

If you want to get the speed of client-side validation, but keep the client clean for maintenance, you can subscribe the onblur event of each form input to do an AJAX call and validate the model, then constrain the form to not submit if the form is invalid. This could all be factored into an external .js file, so all your IT guy has to do is include it, and from there its just HTML.

You always want to aim for better user experience in my opinion. Generally speaking, if your code doesn't add value to the user experience, it doesn't really matter how you implement it in the back end. Having said that, you should always try to write "maintainable" code. If "messy" code is the best that you could do for the time being, add documentations that explains why that is.