Getting Validation Right in ASP.NET Core

When Front-End Meets Back-End: Getting Validation Right in ASP.NET Core

Form validation isn't just a checkbox—it’s a critical intersection of UX, security, and data integrity.

It’s also where front-end meets back-end—and where things often go wrong.

Whether you're using ASP.NET Core with data annotations, or injecting dynamic content like a custom RTE, validation needs to be robust and flexible.

“I remember spending a whole day untangling conflicting validation logic in a hybrid Razor + jQuery form. I wish someone had just built it right the first time.”

✅ The Modern Setup: ASP.NET + jQuery Validation (Without Conflicts)

The trick is to layer unobtrusive validation with jQuery rules, without overwriting one another.

Here's how I’ve done it in DevStack:

🔹 1. Enable Unobtrusive Validation

Include these scripts in your layout:

<script src="~/lib/jquery/dist/jquery.min.js"></script>
<script src="~/lib/jquery-validation/dist/jquery.validate.min.js"></script>
<script src="~/lib/jquery-validation-unobtrusive/jquery.validate.unobtrusive.min.js"></script>

🔹 2. Use Razor Helpers for Data Binding

Let ASP.NET generate the proper data-val-* attributes:

@Html.TextAreaFor(m => m.Description, new {
    @class = "form-control", rows = 10
})
@Html.ValidationMessageFor(m => m.Description, "", new { @class = "text-danger" })

In your model:

[Required(ErrorMessage = "Description is required")]
[StringLength(4000, ErrorMessage = "Too long")]
public string Description { get; set; }

🔹 3. Enhance with Custom jQuery Rules

You can add dynamic checks like word count:

$(function () {
    const form = $("#myForm");
    $.validator.unobtrusive.parse(form);

    $.validator.addMethod("wordcount", function (value, element, param) {
        return value.trim().split(/\s+/).length <= param;
    }, "Too many words!");

    $("textarea[name='Description']").rules("add", {
        wordcount: 200
    });
});

This preserves your back-end rules while allowing for enhanced front-end logic.

🔹 Why Validation Matters

Validation isn't just about showing red warnings:

"Most bugs I debugged for clients started with bad or inconsistent validation. That's why DevStack builds it in from both sides—from the database to the DOM."

🚀 Want It Done Right the First Time?

I’ve already written this code. It’s in DevStack, my battle-tested .NET Core Core 8 platform—ready for projects that need:

You can also check my background in tech and business. I build apps that work—and work for you.

✅ TL;DR

📩 Ready to Stop Fighting Forms?

Let’s validate something together—like your next project.

→ Request access to DevStack or Book a quick demo